Open Thread

Open Thread 23

The last Open Thread is feeling a tad dated, so time for a new one…

The Open Thread is a general discussion forum, where you can talk about whatever you like — there is nothing ‘off topic’ here — within reason. So get up on your soap box! The standard commenting rules of courtesy apply, and at the very least your chat should relate to the general content of this blog.

The sort of things that belong on this thread include general enquiries, soapbox philosophy, meandering trains of argument that move dynamically from one point of contention to another, and so on — as long as the comments adhere to the broad BNC themes of sustainable energy, climate change mitigation and policy, energy security, climate impacts, etc.


By Barry Brook

Barry Brook is an ARC Laureate Fellow and Chair of Environmental Sustainability at the University of Tasmania. He researches global change, ecology and energy.

1,181 replies on “Open Thread 23”

Edward, the gold is stated to be present as microscopic and submicroscopic particles (See page J05). How can hydraulic separation in significant quantities be practical without significant other plant, eg crushing and/or chemical processing, ie conventional mining?

From a first pass through the 400 or so pages of the prospectus and the Geoscience Australia report, it seems that only a dozen or so pages are relevant to discussion of gold extraction – see, especially, the Geoscience data relevant to Deposit 12, Kidston from page G05.

Whether or not the power proposal stacks up I am still unsure, but the proposal is very interesting reading.


I once knew a man who extracted gold from the Columbia river by exactly the means I stated. The whole thing was powered by the flow of the river. He made a whirlpool in the river and collected the tiny gold dust. It paid as well as a summer job would have. He was a college student at the time he got the gold. No crushing is needed because the river already did that by erosion.


A quick search didn’t turn up any progress reports on either the 330MW pumped hydro proposal or the subsequent 150MW PV proposal.

Is Genex Power only generating press releases or is it doing real work? The timeline in the prospectus indicated physical progress by now.


Make it easy for us, William, point out one of those entries refer to progress at getting funding for the pumped hydro? After all, four titles refer to funding the solar farm, but none include the word “hydro”. Perhaps the hydro is being postponed… until Phase Two?



They expect their bankable feasibility study for the pumped hydro to be complete by Q3 this year. As per their latest quarterly report:

“Genex Power Limited (ASX: GNX, Genex or the Company) is pleased to provide shareholders with an update on its activities during its first full quarter since its listing on the ASX in early July 2015.
The December quarter was a busy one for Genex with the Company achieving some significant milestones along the path to delivering a Bankable Feasibility Study (BFS) by the end of Q3 2016.”

Click to access 434llp71b1x6w6.pdf


There is no Colarado River involved, in fact no river at all. The proposal involves pumping water from the low pit to the high pit and generating hydro on the return trip. Any discrete particles of gold will presumably settle out inaccessibly onto the still, cold floor of these two pits.

Mention of a dam and pipeline relates purely to makeup water – not sure, off the top of my head, but at least several gigalitres per annum, ie of the order of a billion US gallons per year.


@ William and Roger:

Remember the maxim “Follow the money”.

This has all of the hallmarksof a Trojan Horse.

Start with a pure pumped hydro proposition which is very interesting given that there are only 3 other comparable projects in Australia and very little scope for more. I have found not even the slightest mention of a Phase 1 PV project in the Prospectus.

Dress the hydro proposal up with phrases such as “black start capacity” and emphasise that the project will make money by arbitrage – buy cheap coal-sourced power overnight and generate when renewables cannot (daytime peaks, inclement weather, etc). The primary market impact of this is to raise the floor on the base load, ie coal fired, portion of the diurnal demand curve.

This was sold to investors, not a year ago, as a 100% pumped hydro project.

The six activities which were prospectively to be completed before the end of Q1 2016 were:
Project Feasibility Study
Environmental Approval Modification
Development Application
Power Purchase Agreement
Transmission Easement Negotiations
Generation Authority Negotiations.

Market reports seem not to mention achievement of even one of these targets, however I may have missed something.

Then comes the exposé. Once the investors’ money was in the bank, the project changed focus to 100% PV with a pumped hydro future option. It became a conventional solar scheme reliant on subsidies from the public purse via ARENA, as they all do.

The corporation’s primary objectives no longer include:
… improving system stability via frequency control (not possible using PV)
… time-shifting from lower to higher market conditions (not possible when the sun isn’t shining)
… and black start capacity (which is adequately achieved via GT’s and thus was worth little or nothing in the market in any case).

It will add to rather than reduce the instability of the northern extremities of the NEM and will increase the need for GT or spinning reserve coal fired generation as backup.

Of course, the formerly Phase 1 but now Phase Two Trojan Horse hydro project is kept alive on paper while the timelines stretch out. That is part of the game. Did I mention prioritising spending public capital over spending shareholder capital or borrowed money? There is an element of that here, as well.

Well done, Directors. You collectively hold millions of low cost options which, no doubt, you hope to exercise when the share price rises for your now heavily subsidised PV corporation. Will the directors cash out and scarper in a few years or stay for the long haul?

Tell me it isn’t so.



I admire your skepticism, and your well thought out post.

I must admit it is a little strange for the company, as you said, to go from a 100% pumped hydro project with no mention of solar to now focus on solar + pumped hydro. At the same time, however, the company describes itself as a “multi-faceted power generation company focused on innovative clean energy generation and storage solutions” (latest qrtly report) so it’s not totally unreasonable to think that the solar project is incompatible with the intentions of the company. If they can get public money from public grants, then why shouldn’t they?

On the other hand, Zhefu Hydropower are substantial shareholders of the company, and their vice chairman has just been nominated as a non-executive director. The Chinese aren’t idiots, if they didn’t think the pumped hydro project was viable or profitable, they wouldn’t have been this involved – unless you think this is some international conspiracy, which I think is ludicrous.

We’re still in Q1 2016, so those activities you mentioned could still be in progress. But I agree with you, doubting their future intentions is important.

A lot of things to think about, and this is exactly the kind of discussion I think is profitable to everyone.



I forgot to ask, when you mentioned:

“It will add to rather than reduce the instability of the northern extremities of the NEM and will increase the need for GT or spinning reserve coal fired generation as backup.”

How exactly does it add to the instability of the NEM?


Thanks for those 2 comments. Yes, it looks like there is something fishy going on. Usual suspects.

Have you been watching DW TV lately? German anti-nuclear propaganda is getting extreme. I must be upsetting somebody.


@ William – 2 places, today:

First, the company floated via an IPO which made no mention of solar power. It has since swapped its single objective to something else and changedits corporate slogan to suit. They are now going down the road of reduced utility and public subsidy. It has not met a single target date as published in the IPO. You may choose to take their word for it, but I have a feeling that there is truth in “Ye shall know them by their deeds.”

How does PV add to the instabilityof the network? There are several deep discussions about this subject on this site, plus a multitude of references on the web.

I suggest Chapter 2 of Although this is a few years old, the engineering is unchanged.

Essentially, any disturbance on a synchronous AC network reduces efficiency. Phase angle, voltage and frequency are all interrelated. Most PV does not come with an ability to correct for these things, so an increasing responsibility falls on the remaining plant to do so. This response might typically come from spinning reserve of redundant coal or oil fired plant or from fast response GT’s.

For these reasons, it is a reasonable approximation to assume that every addition of unreliables must be matched by addition of a similar amount of conventional generating capacity.


AEMO classifies wind farms above 30MW as semi-dispatchable intermittent generators using the Australian Wind Energy Forecasting System (AWEFS).


Describes the objectives,inputs and outputs (forecasts) of AWEFS.

Forecasting timeframes range from dispatch (5 minutes ahead) up to 2 years ahead.

Includes many links. Data is available to researchers.

My opinion: This tool that optimises the use of wind power while avoiding introduction of unexpected risks is a step forward. Readers will know that I regularly criticise intermittent generators such as wind and solar due to their supporters’ unrealistic optimism Vs my engineer’s natural desire to put numbers on everything and to avoid unquantified risks. This tool might reduce the distance between these two opposing viewpoints.


It looks as though the Hinkley Point C EPR will go ahead after a verbal commitment from the French Economics Minister.

From the Hinkley Point website the Engineering Director is confident they had done their homework and have learned from the construction of the 4 previous EPRs, 2 of which will come online in 2017. He says;

“It’s true that there have been problems building the first EPRs and Hinkley Point C will benefit from the experience gained at these pioneer projects at Flamanville in France and Taishan in China.

However most of the problems were related to the fact that the design was not sufficiently advanced before the construction began. They are impacted by the difficulties of relearning new nuclear construction after a 15 year pause in France. The unique standards and certification required in nuclear construction have had to be re-mastered, as have the complexities of these giant construction projects.

Now these skills have been understood through the experience of construction and from all the lessons learned building other EPRs around the world. the nuclear industry and its suppliers will be stronger and more capable in the future.

This experience is a huge advantage for Hinkley Point C. In addition, we have used technology to help us including advanced 3D/4D design tools. That means we know the position of every nut and bolt we need to put in place – we’ve effectively already built our Hinkley Point C EPRs in digital form – so we aim to be one of the best prepared new nuclear project.”

I wish them success because without a strong global nuclear power industry we have no chance of keeping atmospheric CO2 concentrations to manageable levels by mid century.


I recommend Ben Heard’s article at

Reports are emerging that the huge Ivanpah solar power stations use much more natural gas than the projected 1/50th share of the energy output to an achieved 1/3rd, ie optimistic by a factor of 16. This has opened the door to arguments ranging from environmental and contractual compliance to the possible closure of the plant.

It demonstrates the hidden reality which is that solar thermal power is not carbon free, but actually depends on the availability of large quantities of either gas or oil to operate.

The linked articles are interesting also.

When will performance data be available in the public domain that is reliable, actual, measured and audited? That goes for the other commercial, ie subsidised, solar thermal generating plant around the world.

Any claim that solar thermal power is clean energy should be filed alongside claims that cigarettes don’t cause cancer… long debunked and now only believed by those whose commercial interests are at stake.


Anybody who actually did the math knew in advance that Ivanpah was a lie. Solar and wind have been lies for half a century so far and will continue to be lies for as long as people are stupid enough to fall for such nonsense.

If you want carbon free electricity, it is called nuclear fission.



I agree with you that Ivanpah is singularly pointless. Who in their right mind would build a CSP plant without any storage, allow the working fluid to cool overnight, and require heating from gas to get the plant going again. Solar PV can produce far cheaper power while the sun shines.

The real benefit of solar CSP comes with storage.

The Crescent Dunes CSP plant is a good approach, and is in the process of commissioning. It uses 32,000 tons of salt to hold 1.1 GWh of energy, cycling the salt between 500 and 1050 degrees. It took 2 months to melt the salt, but it then stay molten for the 25 years or more the plant will generate. it can stay molten for months, but the point is to generate electricity, not keep salt hot.

It’s capable of 10 hours of generation at 110 MW which would nicely supplement solar PV, and is expected to be unable to generate due to cloud no more than 2 days a year. Or you could take the power as less than 110 MW spread out over more hours per day.

PPA power price is 13.5 cents / kWh for 25 years (plus 30% ITC credit and 1% per annum inflation increments). Compare that with UK’s Hinkley point nuclear at 9.2 p / kWh for 35 years (plus inflation increases). Crescent Dunes is up and all but running and Hinkley is still 8-10 years away. And Crescent Dunes uses new technology while nuclear has been with us for many decades.

Oh, and close to zero bird kills in 11 months since they reprogrammed the heliostats to reduce the standby power to 4 suns everywhere.

Keep your eye on this one which is expected to go into production shortly.


Problem #1: Only 10 hours of storage. It needs at least 168 hours of storage. Why? 10 hours doesn’t cover even a single winter night. It is possible to have a cloudy week, even in Nevada. Also, the sun is at full brightness only within an hour of noon and only in June.

Problem #2: Nuclear: 1.72 cents per kilowatt hour
Crescent Dunes: 13.5 cents per kilowatt hour. 23.22 times the price of nuclear.

“Power to Save the World; The Truth About Nuclear Energy” by Gwyneth Cravens, 2007

Crescent Dunes is a pointless waste of money and time. We already knew that. We also know who wants us to keep on wasting time on solar power: The coal industry.


Nuclear and hydro generation technology are the only proven sources of low carbon electricity generation. Two very good examples are France and the state of Ontario in Canada. Both less than 50g/kWh. See

From IPCC data other good examples are Norway, Sweden and Switzerland all using hydro or nuclear or a combination of both and all emitting less than 50g/kWh.

By comparison countries with anti nuclear political ideology giving priority to intermittent renewables like Denmark, Germany, Italy, Spain and Australia have much higher emissions ranging from 385g/kWh to 885g/kWh.

Click to access t0305.pdf

If we are to reduce emissions to near zero by mid century we must roll out technologies that have demonstrated, real world successful emissions reduction outcomes.

The UK Government support for SMR technology is a good example of the type of science based decision making needed to achieve the emission reductions required.

Once there is a global SMR production industry we can then move onto the production of liquid fuels from sea water as currently under development in the US Navy.


Bringing Crescent Dunes into a discussion of Ivanpah is close to “look – over there” avoidance of discussing Ivanpah.

Crescent Dunes is lauded as 24/7 electricity supply in the comments to the article referenced by Peter Davies at, but it is nowhere near that.

Its availability is nowhere near 100% and is probably significantly less than 50%, as indicated by the last sentence in the article: “So, a typical workday for Crescent Dunes will be a solid 12-hour shift, working for NV Energy from noon to midnight. “, ie 50%.

Allowing for low- and no-sun days and other outages, the availabiulity factor of 40% seems closer to the mark.

That article does, however,make a reasonable point re the symbiotic nature of PV and STP – PV from dawn to late afternoon, STP from noon to midnight.

That assumes a third method of generation to cover midnight to sunup and the no-sun days.

Thus, 3 x 100% capacity plant PV,STP and GT. Three capital costs. Three systems to control.

The EROEI on such a triple technology plant would be woeful.


Back to Ivanpah. It might currently derive 25% of its energy from gas, primarily during morning starts and after sunless days, but at least it does not need to fear freezing of many of tons of salt if something goes badly wrong.

On the other hand, Ivanpah faces shortened life spans due to thermal cycling of its steam parts because they will be heated from ambient on a daily basis and then allowed to cool when the sun sets.

Presumably, keeping the temperature of the pressure parts up overnight and during cloudy periods accounts for a proportion of the huge increase in gas use from the starting budget of 2% to the reported 25% of input energy.


Let us not overstate the low cost of electricity from nuclear power plants. The Columbia Generating Station is a BWR licensed through 2043. The LCOE is estimated to be US$43.39/MWh for this period.

The estimates for the Nuscale SMR, available from about 2025, have an LCOE of around US$95/MWh.


The price of nuclear power did not go up in all countries. Some have more reasonable safety standards and the price did not go up. See “The Myth Of Expensive Nuclear Power” at

The high price of nuclear in the US is caused by coal industry propaganda. On a level playing field, coal and nuclear would be killing the same number of people. Nuclear has killed zero and coal kills 26000/year.


PS: Those numbers of deaths are for the US. Worldwide, coal kills 3 million per year and nuclear killed 52 at Chernobyl.



Problem #1: Only 10 hours of storage

You need to think more about the technology capability and less about this specific implementation.

The energy capture and generation are separately configurable. If you reduce the generator capacity to 40% the heat produced would allow you to generate 24 hours a day. for most days. LCOE would be reduced a little (same energy collected but power generation costs would be much less). This isn’t particularly a useful thing to do because power is going to be shorter during the evening peak.

The reason the configuration was chosen was to support the Las Vegas strip power consumption up to midnight, to enable Las Vegas to boast it was using 100% renewable electricity – with a huge dose of cheap solar PV during the day.

So define your requirements first, then decide how Crescent Dunes technology could be configured to meet them. Australia is an ideal market for solar tower thermal.

Problem #2: Nuclear: 1.72 cents per kilowatt hour

Unrealistic. Crescent Dunes is FOAK. So is Hinkley point at around 13.8 cents / kWh. You are trying to compare NOAK with FOAK, and then adding huge doses of optimism too on the nuclear price.

Already Crescent Dunes tech has been bid in South Africa and Chile at a price less than 13.5 cents/kWh.

As for NuScale, this is 2025. Crescent Dunes is now. You need to compare the solar tower thermal price in 2025 with NuScale. We don’t know this yet but it will be a lot lower.

The real downside to solar thermal is that it is only workable where there is plenty of sun, which does limit the geography. No-one has pointed this out so far, so I will.


The whole country is not Las Vegas. You need to keep the steel mill fully powered for at least 4 days continuously or you destroyed your steel mill.

Do the Math
Using physics and estimation to assess energy, growth, options—by Tom Murphy [physics professor, University of California]
“A Nation-Sized Battery”

The storage has to hold a whole week of full power. Your salt pile will be be too large to be practical. You might try heating a whole mountain.


David Benson said :

Let us not overstate the low cost of electricity from nuclear power plants. The Columbia Generating Station is a BWR licensed through 2043. The LCOE is estimated to be US$43.39/MWh for this period.

It’s a great price for low-carbon generation and is a good reason why the lifetime of existing nuclear stations should be extended as long as possible, compatible with safety and economics.

But the definition of LCOE excludes a generating station which has already been generating for 30 years, so comparing Columbia Generating Station with Crescent Dunes using LCOE is not supposed to be valid.

That’s because it is also true that after 25 years of generation at Crescent Dunes you might be looking at to refurbish it rather than decommissioning it and start again. It will be depreciated by then so the generation costs will also be dirt cheap.


Here’s another of Solar Reserve’s projects – this time in Chile.

[Solar Reserve’s Copiapó] 260 MW project will comprise 150 MW of PV panels for daytime generation, and two 130 MW CSP towers utilizing the company’s molten salt storage, for an installation of 410 MW between the two solar technologies.

By oversizing the CSP, SolarReserve can guarantee a round-the-clock baseload supply for a firm 260 MW at more than 90% capacity.

“Total installed capacity is 410MW, but different parts of the plant run for different hours to provide 260 MW 24 hours a day,” he said.

With a price expected to be well under 10 cents per kilowatt-hour, the pioneering 24-hour solar project in Chile’s Atacama desert can compete on price against other baseload generation. Much of Chile has been dependent on pricy fossil fuel imports from its neighbors.

260MW capacity at 90% capacity factor from a hybrid solar system is probably the nuclear industry’s worst nightmare. Fortunately for them it can only be installed where there really is a lot of sun such as Chile’s Atacama desert – or maybe parts of Australia.


90% capacity is no challenge to nuclear since nuclear runs at 100% capacity for 18 months at a stretch. When nuclear will be down for refueling is predictable. If it is a Canadian CANDU reactor, it can refuel while in operation.
Is that 10 cents in Chilean pesos? If not, the price is too high..
The Atacama is a very rare place, so rare that it needs to be reserved for simulated Mars missions. There is no water to wash those solar collectors in the Atacama. The cost of trucking in water or building a pipeline may be the cost they didn’t count that is going to break the project.

See those clouds in the picture in your reference? They are the other deal breaker. Even in the Atacama, clouds will prevent solar power from working.


Further to what Edward said re steel, the situation with aluminium smelters is even tighter. Pot lines can handle only one hour of blackout, after which they risk damage. That would result in multi-million dollar complete relining of all pots in the line and replacement of electrodes – a huge task.

The point is that many continuous processes require continuously reliable electricity. They must be designed and operated to manage the worst situation, not the average. There are periods when the sun doesn’t shine for a week or two. They must be reckoned with.

References to Las Vegas are clearly only diversionary tactics. When the owner states that the plant is designed to operate noon to midnight, that is what it is designed to do. A quick check will demonstrate that, contrary to affirmations above, Las Vegas operates “24/7/365”. The whole Las Vegas diversion is a meaningless waste of our time.

One frequent visitor to this site seems to be charmed by the partisan website “Cleantechnica”, which exists only to publish gullible fluff pieces about unreliable energy sources. That is their right. However, that does not mean that Cleantechnica is an authority – far from it.

Cleantechnica quoted Solar Reserve’s CEO, Kevin Smith as follows: “ ‘You don’t want to just wait for somebody to call you. After all the sun is shining all day.’ So, a typical workday for Crescent Dunes will be a solid 12-hour shift, working for NV Energy from noon to midnight.”

Peter Davies cited that article, which he now seeks to walk away from. Talk about shifting the goal posts!


The US DoE EIA LCOE document has advanced nuclear down as a 90% capacity factor and an LCOE of 9.2 cents / kWh.

The typical correlation length for clouds is much less than wind – a few hundred km for solar and clouds. There is room in the Atacama desert for four or five areas with independent sunlight and clouds. Each with a 90% capacity factor and each independent.

If Solar Reserve will be bidding less than 10cents / kWh next month in Chile for the second or third hybrid solar generating station ever what will they be bidding by 2025 for the nth station in Australia?

As far as molten salt is concerned, it is otherwise used as fertiliser, so there is plenty of it. The temperature reduction from storage is a degree F per day. For hot salt energy storage for a fixed shape container you would presume the volume would be proportional to the cube of a radius but the area would be proportional to the square of it. Temperature loss would be proportional to the area. So for 8X the energy storage the temperature loss should be 4 degree F per day for a week, or 28 degrees F for the total week (for salt starting at over 1000 degrees F).

By contrast the pressure in the container should be proportional to the radius, or twice as much.

Neither energy loss fraction (less than 1%) nor container engineering (twice as strong) seem to pose a difficult problem if you really did want to store a week’s worth of energy instead of a day.


If you are worried about aluminium smelting then look at what Trimet are doing. They plan to install a new design of smelter which can operate at +/- 25% of the nominal (presumably most efficient) load. The power consumption can thus follow the availability of wind and solar power and the smelter can provide grid stability at a subsecond level.

The hype talks about “virtual battery”, but nowhere have I seen anything other than an ability to control the consumption for days on end within a pretty wide range. But that’s good enough for most purposes.


At face value, Trimet’s nothing unusual – the fact is that once the aluminium starts to solidify it is all over for the whole pot line. Reduced electricity amperage means reduced metal production and a few other inefficiencies but no electricity (or, as appears to be Trimet’s situation, less than 75% nominal) and the troubles start.

Even if all the world’s smelters can survive at reduced load during bad sun weeks, sooner or later the problem arises. Unreliable isn’t good enough for most industrial processes.

Besides which, even overnight at 75% in a Chilean winter will require 75% of 12 to 16 hours – ie 9 to 12 hours storage capacity. A worst case couple of sunless weeks will need 75% of 336 = 80+ hours. How many hundreds of thousands of tonnes of salt/fertilizer is that in a resource constrained world? How many dollars, at (say) $US500/t?

Overselling STP via wild, unsupported and unachievable claims about its capacity will ultimately reduce, not enhance, its prospects. As someone who has worked as a site engineer during construction of three fresnell type STP facilities, I have some optimism for the future of STP, but any claim that it is a reliable 24/7/365 electricity source is fantasy. It simply can’t do the job and consequently will continue to need support from more reliable sources. My concern is that those sources will, as at present, be primarily fossil fuelled, thus locking us all into high carbon futures.

Mr Smith, Solar Reserve’s CEO, was correct not to raise expectations above 12 hrs per [sunny?] day. That is achievable. He requested that his plant not be used for peaking or standby. He wants preferential market access on his own terms. They might be biased but at least he is being reasonable and he has a good chance of meeting his customers’ expectations regarding availability and reliability (ie, not much).


singletonengineer said :

Overselling STP via wild, unsupported and unachievable claims about its capacity will ultimately reduce, not enhance, its prospects. As someone who has worked as a site engineer during construction of three fresnell type STP facilities, I have some optimism for the future of STP, but any claim that it is a reliable 24/7/365 electricity source is fantasy. It simply can’t do the job and consequently will continue to need support from more reliable sources. My concern is that those sources will, as at present, be primarily fossil fuelled, thus locking us all into high carbon futures.

If you want to get the capacity factor of an Atacama solar tower thermal plant from 90% up close to 100% there’s a very simple and cheap solution.

You install 25% of the plant baseload capacity in additional solar panels plus water electrolysers to produce hydrogen. Add two weeks – what the heck, let’s make it a month! of hydrogen storage (cast iron gasometers in UK in the good old days of the coal gas (mainly hydrogen) gas grid). Then put in an hydrogen burning steam boiler in parallel with the hot salt to steam boiler and piggyback on the steam turbines / generators already installed. There are already condensers for recovery of liquid water from steam so the combustion hydrogen could piggyback on this process which would need very little additional capacity.

That should do the trick at a very reasonable cost, given the steam turbines / generators are already paid for and the extra solar PV panels wouldn’t need grid-capable inverters so would come in well under 4 cents / kWh.

What do you think?


On and off over a period of more than 30 years I have been involved with hydrogen generating plant – of which storage at both low and high pressures is an integral part.

Three hydrogen fires later, including one that demolished a truck load of cylinders and the truck itself and one that did its best to demolish the hydrogen generating plant’s walls and roof have made me very wary of the stuff. Besides which, it is currently more economical to obtain commercial H2 derived from natural gas and delivered by road to the power station by road than it is to generate it ourselves, even with plant that has been fully paid for and with electricity at the marginal fuel (coal) cost of production – about 2 cents per kg. The labour cost is also nil because no currently employed operator, maintenance person or engineer will be sacked because of a decision not to use the hydrogen generating plant.

I won’t rush to a conclusion as to whether a round-trip efficiency of 20% or a bit better is an appropriate use for surplus solar or wind power.

I also do not buy Peter D’s idea that solar thermal, in any configuration, has been shown to achieve 90% availability. Even if it did so, its capacity factor would still be at the 25% or 30% mark.

Speaking of capacity factors, in order to extend the availability and/or capacity factor of a solar thermal generato requires additional expenditure. It is certainly not free. Let’s say that the steam driven turbine and generator are going to run at 90% capacity but that the base case, with balanced nameplate ratings for the solar collectors and the power plant is a third of that. Straight away, it becomes obvious that the solar farm needs to be upscaled to 300%. The energy thus collected would either go to storage or directly to generation and thus to the load.

BUT, and it is a big but, if the cycle through hydrogen generation and back to heat in the boilers is only 30% efficient (I think that this is an extremely generous assumption), then it will take 3 units of solar energy collection to produce 1 unit of additional output to meet demand.

So: First 30% capacity factor costs X square metres of solar collector.
The next 60% of capacity factor costs 3x 2 = 6 times as much solar farm.
Total = 7 solar farms to get that 90% capacity factor.

Is anybody really contemplating sinking that much capital, in a variety of technologies, just to chase a mythical 90% availability? Or, worse, a 90% capacity factor?

The non-storage – free 25% natural gas 12hours per sunny day Ivanpah has none of this overbuild.

I simply cannot believe that Atacama achieves 260MW from a collector field less than twice that whilst concurrently achieving 90% capacity factor. The losses in the steam cycle would more than account for the difference between a 410MW solar thermal array and a 260MWe output, whilst setting nothing aside for the non-sunny hours and days. The stated 90% capacity figure cannot be trusted – it is a fiction and is optimistic by a factor of perhaps 10.

What I think about the economics of solar thermal power supported by solar PV plus hydrogen generation plus hydrogen fired boiler system is not relevant. What is relevant, and this is a point that I seem to keep coming back to, is that conceiving a hypothetical system is nowhere near demonstrating that it can work reliably.

I am not interested in idle musings about what might be. When the demonstration plants are running and independently confirmed results have been peer reviewed by those much more knowledgeable than I am in the various technical, statistical and economics disciplines, we will all know.


@ Peter D:
I may have too readily displayed my frustration with sales-speak and unbridled optimism and, in doing so, steered away from the genuine enthusiasm I once had for solar thermal energy technologies, either as steam generators feeding into conventional boiler/turbine/generator power stations or as the full box and dice from sunshine to high capacity grid-connected solar thermal power stations.

That is in part because of my background as an engineer in design, construction and maintenance of capital projects generally, up to 2600+ MW power stations.

None of the three solar thermal arrays that I have had the pleasure of supervising during the construction stages has been a commercial success. I have been a participant in the STP (solar thermal power) industry for almost two decades and have had the opportunity to see significant dollars spent since the early trials. STP, at least as represented by fresnel collector arrays (rows of steerable mirrors under steam tubes) is no longer a FOAK technology. It is mature and it is not a pot of gold. Future advances will be incremental and hard-won.

Others, primarily in Western nations such as Australia, USA (where the original Australian company moved to in the 1990’s), UK, Spain, Germany, have all put billions of dollars of private and public money into the hunt for commercially successful large scale free thermal energy from the sun.

I am yet to read an independent, peer reviewable, technical report of a commercially successful and reliable STP project anywhere in the world, with or without storage options such as batteries, hydro, hydrogen, molten salt; whether using power tower technologies or fresnel arrays; and whether coupled with PV or other systems.

They simply don’t yet exist and, when they do turn the corner to commercial reality the road ahead will be as slow and expensive as the experience of the past couple of decades.

I would love solar thermal power to be successful and plentiful but it simply has not been shown to be so, anywhere in the world. It is still being developed, slowly and tentatively. It is currently a rich man’s toy and I personally know some rich men who were much richer before they became involved in this endeavour. I’m talking losses of tens of millions of dollars of private wealth on investments in the 8-figure range. These are experienced investors with hard heads and good advisors, but who have left the game after giving it their best shot.

Whether Google/Alphabet and friends have a similar experience in the Arizona desert remains to be seen.

It is a mistake to assume that commercial STP, at any scale, has arrived and that it is poised for a great leap forward, or that batteries or compressed air or any of the other commonly mentioned storage technologies are mature and economically available off the shelf to save the day. They, too, are emerging slowly, as also Type IV nuclear.

Meanwhile, the biggest question that the world has ever faced remains “What can we do in response to climate change?”

It is not “How can I increase the uptake of wind and solar power?” – that is relevant only to salesmen.

At this stage, I believe that the answer is, substantially, currently proven and demonstrated designs of nuclear power.

We must avoid delaying doing the possible as we search for perfection.


All the authenticated ERoEI figures I’ve seen for solar thermal power come in underneath that of solar photovoltaic panels. That, and the fact that solar thermal opportunity exists in listed locations around the world, would seem to render it a very doubtful technology. .


Likewise. Would be nice to see one operating. Not that it would solve the world’s problems, but had the potential beat the pants off other solar technologies. One was due to be built near Mildura, but didn’t get off the ground. I’m presuming the economic return was questionable or it would gave done so.


Some readers may be interested in this – if nuclear progress had not been disrupted in the late 1960s and since, the position now (if learning rates demonstrated up to about 1970 had continued) would be (approximately):

The overnight capital cost of new nuclear plants would be around 1/10th of what it is now
Nuclear power would have replaced just about all baseload fossil fuel electricity generation
This would have avoided around 5 million fatalities since 1980 and about 300,000 in 2015
Avoided an additional 85 Gt CO2 since 1980

High learning rates were achieved in the past and could be achieved again with appropriate policies.

more … Nuclear power learning rates – policy implications


These things are red herrings. As SingletonEngineer says, it is desperately important to focus on converting all our electricity to nuclear and all energy to electricity. Our descendants will condemn us for our delay.


Red herring: something, especially a clue, that is or is intended to be misleading or distracting.
Exactly. The coal industry, its shills and its dupes, continue to waste time by diverting us to wind and solar power. Wind and solar are purely propaganda designed to prevent the demise of King Coal. As the coal industry knows perfectly well, if there is no resistance to nuclear, King Coal will die immediately. Nuclear is very dangerous if you are the coal industry. Coal is the one that is dangerous to people.

The “social movement” to achieve personal energy supplies rather than rely on “evil” corporations is also a red herring. What we are trying to avoid is a population crash caused by Global Warming, overpopulation and resource depletion. Overpopulation cannot be solved by moving people about. Corporations are not the source of the problem except for the fossil fuel industry. Attacking the collective nature of the electric utility industry is counter-productive.


The only scenario for Solar PV going baseload is when we have a space-faring civilisation that can cheaply mine the asteroid field for everything they need (including uranium and thorium), manufacture solar PV out there, and fire huge solar PV space stations into orbit for the good-old “space based solar power” network. Or maybe we’ll mine the moon.,417113

Or maybe we’ll “marry” the moon, and put a ring around her.

But all of this is generations away, and may forever remain completely unaffordable compared to cheap mass produced breeders.


Chris Harries said :

All the authenticated ERoEI figures I’ve seen for solar thermal power come in underneath that of solar photovoltaic panels. That, and the fact that solar thermal opportunity exists in listed locations around the world, would seem to render it a very doubtful technology.


You would expect the EROEI for CSP / STP to be about half that for solar PV (assuming the same lifetime) to reflect the cost ratio – PV is half the price of CSP and will continue to be cheaper even as the costs of both come down.

But that’s not the whole story. Solar PV is destined to be so cheap that you should be using it when you can, but it can never generate when the sun is not shining. Whatever you do outside daylight hours is always going to be more expensive than solar PV.

So the EROEI comparison is not a reason for ditching CSP / STP.

The locations suitable for installing CSP + storage are generally the sub-tropics and tropics.

That might sound like it disqualifies CSP, but in the long-term, HVDC lines with very low losses (3.5% per 1000km) can be justified to pipe this power up to 2000km away to quite a few of the large human population centres.

Saharan CSP is within reach of Europe up to UK and Berlin.

Western China CSP will probably be connected to the population centres in the East of China. It is not scared of 50 year investments in UHVDC lines across the width of the country –

Australia has reasonable CSP available in the interior but zero political will to exploit it.


Hi Peter, I think tropics and sub tropics – accepting that most of these areas have high humidity and cloud cover – is a tad too broad. Certainly there’s scope in dry, cloudless parts of Australia, Spain, Arizona, northern Argentina and the Sahara.

Australia has about as much scope as anywhere, but these beasts still have to prove themselves in terms of what energy and resources go in to get satisfactory net energy and financial returns.

Major solar thermal is an attempt to try to make solar become a player in large centralised power formats, but I think it’s generally the wrong way to go. If push came to shove and I had to back one over the other I would back pv technology because it lends itself better to distributed power, powering of local village communities and represents a divergence from vertical utility structures.

If we wanted to stick with that basic centralised power format and turn off coal then solar can’t do it globally.


More wishful thinking from one with the blinkers on.

To pretend that HVDC transmission only costs 3.5% energy losses per thousand km is to avoid the other inescapable costs, including the capital and operating costs of the transmission lines themselves.

When, after WW2, the Electricity Commission of NSW was established, an early task was to review augmenting the existing infrastructure, which was inadequate. It included 5 Sydney Harbour saltwater cooled coal fired power stations, fed primarily by sea from Newcastle in ships called the “60 Milers”.

Options included redesign of the Sydney power stations and the sea. road and rail transport systems which they relied on.

The adopted alternative was to construct between 1960 and 1993 over 10 GW of coalfields based new power plant at Munmorah, Wallerawang, Vales Point, Liddell, Eraring, Bayswater and Mount Piper. Essential to these were new 330kV and 500kV transmission lines to bring the electricity to the load centres. The cost of this was included in the plans from the outset.

One cannot pretend that transmission lines are Other People’s Problems or that they are irrelevant when considering STP and SPV – either they are included up front or the cost of providing them will be paid later by way of financing charges and usage fees – in the end, the users still pay.

At the risk of repeating myself, the reason for the Sahara not being covered with solar panels and mirrors powering the whole of Europe is not that the panels and mirrors are expensive. A buyer seeking a Landrover in England will not consider buying from a dealer in Timbuktu, regardless of price, without considering the cost of delivery. The same applies to electricity.

Those advocating a desert full of hardware must consider the complete system, including HV transmission.

No amount of diversionary hair-splitting, red herrings, cherry-picking, obfuscation and wilful blindness can change the simple fact that Saharan Solar anything has never been demonstrated to be fit for purpose, adequate and economical for supply to Europe. If it was, then we would not be having this discussion again.

The discussion is about SYSTEMS, not about COMPONENTS.


Morroco is constructing a large solar thermal project, to avoid importing so much electricity from Spain. I assume that the economics is favorable as the government of Morroco is known for avoiding show.

The net effect is to make more generators in Spain available for the loads from the Iberian region and for transmission to France over the rather weak interconnects.


France’s policy to reduce nuclear share of electricity generation from about 75% to 50% would increase the emissions intensity of electricity generated in France by about a factor of three. Emissions intensity would increase from 44 g/kWh in 2015 to about 150 g/kWh. For comparison, emissions intensity of electricity generated in Germany is about 475 g/kWh in 2014, (IEA).


We don’t need more nonsense on solar power. Go back to college and get a degree in electrical engineering.


So my question for Cambridge University engineering department is how did you wind up working against the public good? We have given you plenty of reason to understand that solar and wind are nothing more than time and money wasting loops. The goal is to stop Global Warming before civilization collapses, not decorate the desert. You should be able to understand what we told you. Instead, you act like a hidden [crypto] denialist.

Some people are agreeing with Barton Paul Levenson, except for the date, that famine will collapse civilization. They are saying 2040. Bart is saying possibly 2022 to 2034.

View at

Click to access food%20system%20shock_june%202015.pdf

Generation 2 nuclear works well enough. We don’t need anything more advanced. Nor do we need technology that we won’t have for a century. Yes, I’m in favor of research, but not in favor of holding up solving a problem that we needed to solve in the 1970s.



Fresnel trough + steam systems cannot readily be used with storage, so solar PV probably overtook them some time ago in terms of economics.

Solar tower with hot salt and storage seems to have advantages over Fresnel reflecting trough systems. The distributed equipment is simpler, apart from the requirement for two axis tracking instead of one. The salt can be heated in the solar collector tower to a higher temperature than oil (or steam) in the trough pipes, and there are no losses from transferring the heat from oil to salt for storage. It is straightforward to overconfigure the heliostats to provide full generation power in winter as well as summer. In summer or at noon you just don’t point all of them at the collector (or you might break it)

The higher steam input temperatures equate to a bigger efficiency improvement than you might think because most of these systems are in deserts and for daytime operation the thermodynamic exit temperature of the steam is high than normal. The storage capacity is improved when CSP generates at night, so a hybrid daytime solar PV + nighttime CSP system is good. In the Sahara I spent a very cold couple of hours viewing the spectacular star field through binoculars before spending a night freezing in the coldest bedroom with no heating that I can remember. The much lower steam exit temperature at night again increases the thermodynamic efficiency compared with a daytime-only system, improving the storage time over what you might expect.

Solar Reserve is very proud of its solar collector tower which lets them work at a high temperature. The US is subsidising Solar Reserve’s research to find materials for even higher collector temperatures which might improve thermodynamic effiency and reduce the cost further. There’s a thermodynamic limit. The temperature of the collector depends on the thermodynamic temperature of the sunlight filtering through the (clear) atmosphere and the ratio of the solid angle of all the reflectors at the collector divided by the possible 2 pi solid angle. But current systems are way off this.

Solar Reserve uses heliostats with separate IP addresses on a common network which has to point them all in different directions to reflect sunlight onto the tower, although many competent engineers working with programmers could solve this particular problem.

These improvements over Fresnel trough are not individually big deals, but as an engineer, surely you have to wonder whether together they constitute a step change in the practicality and pricing of solar thermal. Solar Reserve’s projects look like the real deal to me.



At the risk of repeating myself, the reason for the Sahara not being covered with solar panels and mirrors powering the whole of Europe is not that the panels and mirrors are expensive. A buyer seeking a Landrover in England will not consider buying from a dealer in Timbuktu, regardless of price, without considering the cost of delivery. The same applies to electricity. Those advocating a desert full of hardware must consider the complete system, including HV transmission.

Of course you have to factor in transmission lines.

The funny thing about transmission lines is that the more you use them (high capacity factor), the lower the increase in LCOE from generation due to transmission.

Here are some figures for the Wyoming Carbon County HVDC lines into California. They exclude any maintenance costs for the lines. They are to support a wind farm in windy Wyoming.

46% – expected CF (40-45% from PR stuff or 46% from NREL documentation)

1.43 cents / kWh – expected addition to LCOE – 1.43 cents (lifetime 40 years, discount rate 5%) . This figure does not include O&M costs because there does not seem to be any good documentation on this.

730 miles – total distance

The distance from London to Ouarzazate, Morocco, site of a new (disappointingly trough + oil) 160MW CSP generating station with only 3 hours of storage is 1460 miles, or twice as far. See

HVDC line termination costs tend to be weighted towards the equipment at either end, rather than the pylons and wires. See

Now take a capacity factor of 80% for Saharan hybrid solar (combination of solar PV daytime and baseload solar tower CSP with storage). This reduces the transmission line LCOE to 46/80 x 1.43 = 0.82 cents / kWh. Twice the length with a second set of converter stations would come in lower than 2 cents / kWh. Line losses 7%.

A combination of a solar tower CSP as deployed in Chile at 9.7 cents / kWh (give or take for any difference in direct sunlight hours), plus 2 cents transmission line costs to London comfortably beats EDF’s Hinkley point nuclear generation at 13.5 cents/kWh (=9.2p/kWh). And while advanced nuclear is supposed to hit 90% capacity factor, the current load factors for UK nuclear stations for the years 2010-2014 were 65, 66, 71, 74, 67% respectively (table 5.9 in )


Nuclear here runs at over 90% capacity factor and the 10% is for refueling. Why will Hinkley point nuclear be worse than our old reactors?


Peter should return his engineering degree to Cambridge.

Despite many requests for current data, this “engineer” persists with use of unreliable, imaginary data.

Without verifiable data, there is nothing to go on. Not expectations and dreams – real, measured numbers. For example, 80% availability factor? Says who? Where? At what capacity factor? How achieved? Plant descriptional? The engineering details are not unimportant – they are the keys.

Peter is embarassing other engineers by treating his readers as gullible children. This is about real world problem-solving, not competing for the biggest and best dream.

Most important: What are Peter’s commercial interests in energy alternatives? Who pays him? Is personal disclosure optional or essential?


The recently completed eastern Alberta hvdc, 300 MW, 500 km, transmission line required $1.8 billion. I assume that is Canadian dollars.

The western Alberta hvdc transmission line is 350 km for $1.7 billion.

According to Wikipedia both projects have a 1000 MW capacity.


Roger Clifton — Including the 1.2% loss in the pair of converters at the ends, about 35 MW over the 500 km at full 1000 MW input. So about 0.0046% per km plus converter loss.


Peter Davies — Determining the LCOE of the Columbia Generating Station, a 1172 nameplate MW BWR, is indeed the correct approach to determining whether to replace it before the renewed license expires in 2043 or to keep it running until that date.

This is not an easy decision as the LCOE is at the upper end of the Mid-Columbia Hub price range for firm power. I infer that the unit loses money so depends on the other generators run by Energy Northwest to keep it operating. Despite this, the conclusion of a study was that premature shutdown would cost a billion dollars more than running it to 2043.

And have I mentioned how inexpensive electricity is here in the Pacific Northwest compared to elsewhere?


I make it 0.007 %/km – plus connections – but even so, it is impressively lossless. It seems odd that California should be hungry for power that the NorthWest could supply so easily. What am I missing? I’ll be there next week, will have to ask around.


California did something very foolish: They closed nuclear power plants and passed renewable energy mandates. Why did they do that? Because musicians convinced them that nuclear is dangerous. The truth is that nuclear is far safer than renewable energy, and musicians don’t know anything about it.


Ahem. Not a good idea to make enemies of all musicians, Edward. Most of them are not into energy policy. It’s not really their scene.

There is a level of anti-nuclear sentiment throughout society – including religious leaders and health professionals. I don’t think musicians have much ranking in the scheme of things.


“Most of them are not into energy policy. It’s not really their scene.”
Let’s hope so. I heard it was Peter Paul & Mary, but I have little confidence in that identification. The phrase “nuclear poison” was supposedly in the song. Do you know that song? It was after I quit paying a lot of attention to popular music.


Yes, well, don’t know the song, it wasn’t one of their better known ones, but you are talking about a long time ago, when the Cold War Arms Race was still at its peak. There was probably good reason for them to sing about that, if that was the context. The world was on edge.

At all times you will find protest singers who support various causes, but protest singing as a genre is nowhere near as strong as it once was. How many songs have you heard about climate change? Nobody seems to sing about it.


Roger Clifton — The Pacific Northwest wheels as much power as is available down the Pacific Intertie. First, there isn’t any more hydro. The Pacific Northwest is down to about 65% hydro as it is. Some more raw wind power, to be balanced by California resources is possible, but that requires upgrading the Pacific DC Intertie . A modest upgrade is in progress. Anything more requires obtaining right-of-way. I opine that would require at least 2 decades of planning and permitting.



Despite many requests for current data, this “engineer” persists with use of unreliable, imaginary data.

Without verifiable data, there is nothing to go on. Not expectations and dreams – real, measured numbers. For example, 80% availability factor? Says who? Where? At what capacity factor? How achieved? Plant descriptional? The engineering details are not unimportant – they are the keys.

Given the number of direct sunlight hours in a year, for instance, in a location in the Sahara, and confirmation that the interruptions for cloud are randomly distributed and not, for instance, clustered in winter, what equipment details do you require for a baseload solar PV plus solar tower CSP plant that would make any difference to the capacity factor?

My assumption is that the designers are capable of doing spherical geometry and therefore the plant bid to deliver baseload power is suitably configured to deliver 24 hours at the defined power on the shortest winter day of the year at a capacity factor of direct sunlight hours/year x 2 / 8760. Equipment failures excepted.

And, while they may not understand their own equipment perfectly before the first implementation, as soon as that is over they have the required information to configure other systems to hit that capacity factor (equipment failures excepted).

Over to you.


What else is in the Sahara?: Muslim extremists. How long would your solar farm and power line last?: Maybe a week. Yes, an engineer has to think about that. There is not much political stability because there is not much food. There is not much food because of Global Warming and overpopulation. There are plenty of weapons.
Who says? Nature. It’s not nice to fool Mother Nature and not even Peter Davies can do it. IF Peter Davies really did have a degree in engineering, Peter Davies would know enough of the laws of Nature to answer his own question.


Peter D, it is not “over to me”. You have made many unsubstantiated claims and have desplayed extreme reluctance to state your personal conflicts in this discussion.

It is you who need to bring proper data to the discussion, or admit that the data to justify your claims simply doesn’t exist. Your position is both irrational and untenable. Good luch with that in the real world.

Without engineering data, you are representing vapourware… gas.


Re the reliability of HVDC, search for news items on the interconnector between Tasmania and Victoria, Australia.

From memory, it failed two months back and current expectations are that repairs will take anouther couple of months.

Tasmania is primarily hydro-dependent. Their largest non-hydro power station, 270MW GT, was mothballed a couple of years back.

Emergency arrangements have included restoring the GT to service, negotiating reduced operations by the largest industrial users, who also happen to be large high value added employers, and rushed purchase of scores of containerised diesels.

One unexpected side effect has been the loss of the primary data link via fibre optic capacity which was included in the 400kV HVDC undersea cable bundle. Tasmania currently has reduced industry, reduced water in dams (less than 15% full and down to 7% in some dams), mounting costs of the remaining power sources, plus constrained data capacity.

Welcome to the world of HVDC interconnectors. Failure isn’t simple or pretty. Complicated systems have complex failure modes, as any real engineer appreciates – though this does not necessarily imply that every simpleton claiming to be an engineer is fully aware of the complexities and inherent risks which are present in novel proposals.

Basslink: Wikipedia.
Interconnector failure: or wikipedia.


Edward, PP&M rose to fame mid-1960’s, during the Cold War era. Nuclear weapons testing in China, USSR, mainland USA, Marsall Islands, French Polynesia and Australia, amongst others.

The risks that PP&M primarily referred to (if memory can be trusted) initially had little to do with electric power generation, which remains irrationally tarred with the same brush despite 50 years of absolutely stirling safety records globally.

Unfortunately, PP&M did morph into rabid anti-nuclear propagandists, but this came late in their careers. Musicians, or at least some popular musicians, have a lot to answer for regarding giving nuclear power an undeserved bad reputation.

Early in 1978, Yarrow was busy putting together Survival Sunday, a benefit concert at the Hollywood Bowl to oppose the spread of nuclear power. “I always was able to do the organizing that I had done in the past by virtue of saying, ‘Well, Peter, Paul and Mary are doing it.’ and then other people would jump on board,” Yarrow said. Already on the bill were many of Yarrow’s friends; “Gene McCarthy was there, Cesar Chavez, Mike Farrell, Allard Lowenstein, Robin Williams, Tom Paxton, Sweet Honey in the Rock, George Carlin. It was a lot of folks that I had worked with before, and I needed to draw some 2,500 people. So, I called up Mary and Noel, and I said “I’m doing this, and do you believe in the importance of this?’ Of course, this was the first worldwide environmental movement. And they said, ‘Yes.’ ”



singletonengineer — The Pacific DC Intertie from the Pacific Northwest to Southern California has also had its share of troubles, being down for extended periods on at least three unscheduled occasions. See Wikipedia.

Even when working it sometimes only transmits about half the time for reasons unknown to me and it seems not pleasing some in BPA Transmission Services.


Edward does have a point there. Over the last century or so, the respect from the countryside for the growth of western-style urbanisation has been shaped by the seemingly endless successes of western technology. However it is rural folk who will first identify that the weather is becoming less predictable, and droughts and floods more common. It will be quite easy for grass-level preachers to point out that the rage of God has been invoked by the sins of western man.

The streets of foreign cities are likely to become less safe for westerners and western ideas, let alone their own urban dwellers. When global decarbonisation threatens to take away hydrocarbon fuel from their Toyotas at the same time as their crops fail and refugees from worse hit areas threaten to take what is left, large-scale unrest will be inevitable.


Peter Davies — In the USA the nuclear power plant fleet average capacity factor for 2015 was 0.919. The downtime was primarily for the 18–24 scheduled outage for testing, refurbishment and replenishment. There were a few unscheduled outages for equipment failures but none lasted for long. The EPR nuclear power plants will demonstrate about the same availability and as will run as much as possible so demonstrating the same capacity factor.

I have no explanation for the low capacity factors of the British nuclear power plants. I suspect policy but you are better situated to determine this than I.



Here is the web site for Solar Reserve which gives details of their technology.

and here’s the technology link

As you can see, the projects can independently configure the heliostat field, storage tank sizes and boiler and generation capacity. That’s all I needed to know about the technology

And here’s a link to a the map of direct sunlight hours per year

Now tell us why, excluding equipment failures, a hybrid solar PV / solar tower CSP cannot achieve a capacity factor equal to direct sunlight hours x 2 / 8760, provided the cloud etc. is randomly distributed throughout the year and not concentrated in winter. For the Sahara cloud is less likely to cluster in winter, incidentally – .

As far as my motivation is concerned, I have nothing to do with Solar Reserve or any other energy company, other than owning index-linked shares in a global technology fund which probably includes both nuclear and renewables.

IBM pays my pension. Past IBM customers I have worked with include Merseyside and North Wales Electricity board (1978-79) and Shell (1988-1989).


Peter Davies has confirmed that he is not paid to misinform us – he does it for free.

The so-called technical pages he referred to give no indication of how any particular project is configured, what its capacity factor is (NB “availability 24/7” is an aspiration, not a fact) and how the surplus energy required to replenish storage affects the size of the collector field. There is no indication of the reliability or capacity factor of the constructed power station – if one is ever going to be completed.

Critically, there is no comment about the relative energy-collecting capacity of the system on a mid-winter’s day and how the scale of the collectors matches that of the generation plant and the thermal store of salt.

If 24/7 means all day, every day, for at least a week, then an overcast week in a winter’s month of 9-hour days will require arrays that are of the order of 10 times the size of an array sized to just meet 100% capacity during a sunny summer day of 24 hours. I won’t bore readers with the maths or the assumptions – Peter isn’t interested in them either. Such a huge collector field would annually collect many times the energy that could be generated and dispatched 24/7. No commercial operator would do this, so the 24/7 claim must have caveats – perhaps overnight load is assumed to be a fraction of the daytime loads. Perhaps no day is assumed to be entirely cloudy. Perhaps there are diesel heaters to top up the oil temp on bad insolation days and months. Remember, 25% of energy sent out from one large 12/7 solar thermal operation was found to be diesel powered – discussed above.

So, Peter cannot be concerned to know the nature and duty cycle of the emergency backup plant and may indeed be magically convinced that none is necessary, despite there being absolutely no information available to demonstrate this to be true.

Peter has provided nothing about what public finance is required to support the project or whether marketplace advantages have been demanded and obtained by the proponents or whether it is on a level playing field with all others, or at least all that claim to be very low emitting generators – and remember that any claim that a technology is zero carbon emitting (yes, such a claim appears on the cited links) is intentionally ignoring all emissions during construction and operation, including those relating to transport and services. And diesel support.

One primary feature that distinguishes professional engineers from the remainder of the world’s population is the engineer’s ability to problem solve, using initial assumptions and known principles to calculate in advance the performance of that which has not yet been constructed and/or to collect and analyse data from society’s machines in order to verify successes and to analyse failures.

Peter has presented us with assertions based not on observations, knowledge and analysis, but on a complete lack of disclosure of performance, either actual or calculated. We have received nothing of engineering value to inform or to review. There are a few opinions regarding 24/7 availability (at what capacity factor?) and an assertion regarding complete lack of emissions or waste… which is far from a cradle to grave analysis.

Peter has been had. He has been sucked in. His leg has been pulled. He has had the wool pulled over his eyes. Having fallen for the spin, he now demands that others should do likewise and that discussion must turn away from the analysis and numerate comparison which are essential to rational decision making.

On top of that, Peter has the gall to state that his work as an engineer is completed, that it is others who have failed to see the light. He should be calling for those who have convinced him of the veracity of their claims to justify the claims made in the glossy brochures. He should continue to review, to search and to question until he is in possession of testable facts that prove the assertions.

Accepting sales blurb at face value isn’t engineering – it is intellectually lazy consumerism.



In the USA the nuclear power plant fleet average capacity factor for 2015 was 0.919. The downtime was primarily for the 18–24 scheduled outage for testing, refurbishment and replenishment. There were a few unscheduled outages for equipment failures but none lasted for long.

2015 is a very cherry picked year :

I have no explanation for the low capacity factors of the British nuclear power plants. I suspect policy but you are better situated to determine this than I.

In these days of the Internet it is difficult to see why you do not have access to the same material in English as me.

However, perhaps you would like to explain the low capacity factors during most of the lifetime of the US nuclear industry instead.

The EPR nuclear power plants will demonstrate about the same availability and will run as much as possible so demonstrating the same capacity factor.

Despite construction starting in 2005 and 2008, the first two EPR reactors are still not running, and the projected live dates are both 2018. The problems appear to have been mainly technical – welds and metallurgy. The issue then is that other technical problems may well surface later which delay the live start dates still further. And there is no guarantee that there will not be more problems after live running commences. The two Chinese EPR reactors haven’t fared much better either.

The issue with all this is that a technology which takes the best part of a decade per project and requires very skilled design and engineering resource cannot be rolled out fast enough to have an impact on CO2 emissions and therefore global warming before 2030. Not to mention that the list of countries which believe that nuclear technology has and will continue to shoot itself in the foot tends to grow as time goes on.

By contrast the Chinese can install a new wind farm in a few months, though renewables priority policy changes and transmission upgrades take them a little longer. The speed to install is one of the reasons why Chinese generation from wind overtook that from nuclear in 2013.


There was a learning curve on reactors. This is expected, especially when a different reactor is designed for every installation. We are getting over that by having reactors certified for factory production. Factory production will allow the workers to learn their jobs and will allow quality checks in the factory.

Wind and solar have capacity problems that are built in by Nature and you have no control over them. For example, nocticulent clouds that you can’t see from the ground, dust storms, night, hurricanes blowing them away, space weather such as a coronal discharge cloud from the sun. giant molecular clouds from another solar system, and so on.


We know why nuclear got more expensive: Coal company agitation and propaganda over non-existent radiation safety problems. See
It is wind that kills more people. Nuclear has a perfect safety record of not having killed anybody in the US. Even Fukushima killed zero people. But the propaganda continues.

Please read Reference book: “The Rise of Nuclear Fear” by Spencer Weart. The fear started thousands or millions of years ago with the fear of witches, wizardry, magic etc. The design of the human brain is very bad. See “Religion Explained” by Pascal Boyer.

“The Rise of Nuclear Fear” by Spencer Weart needs “Religion Explained” as background. A lot of modern first world people do magical thinking rather than logical or scientific thinking [not all logical thinking is scientific]. That is, they think of technology and things they don’t understand as magic. That is especially true of anything “nuclear.”

The US government did a lot of propagandizing about nuclear things in the 1950s. Some US government officials used secrecy as an instrument of political power at the same time. The secret is:


Nature is an open book. Nature is the same everywhere. Any country with enough money, sanity, scientists and uranium can make a nuclear bomb. Most that could, chose not to. Iran seems to be stuck by a lack of something cultural. Uranium is mineable in most countries and we know how to get uranium out of ocean water.

There is no possible way that a reactor could ever become a nuclear bomb. Chernobyl did not. I will have to tell you a little about how to make a bomb to explain the difference. Nothing classified.

All of Generation 4 reactors are intrinsically safe, relying only on Nature for safety. Spent fuel is fuel for Generation 4 Integral Fast Reactor. Read the book: “Prescription for the Planet” by Tom Blees, 2008; and read
free download:


Peter Davies — That is only some of the data. A more recent analysis is explained and linked in a prior post to this thread. As it is, your prejudices are showing. Do strive to be objective and to keep up.

Thank you.



The question was whether there was anything to stop the Solar Reserve technology being configured to meet the customer requirement, which was expressed as baseload generation of a fixed output with a capacity factor of

(direct sunlight hours / year) x 2 / 8760.

Instead of taking the trouble to understand the technology and analyse how such a requirement might be met with it, singletonengineer comes up with :

If 24/7 means all day, every day, for at least a week, then an overcast week in a winter’s month of 9-hour days will require arrays that are of the order of 10 times the size of an array sized to just meet 100% capacity during a sunny summer day of 24 hours.
There are a few opinions regarding 24/7 availability (at what capacity factor?) and an assertion regarding complete lack of emissions or waste which is far from a cradle to grave analysis.

This response is from someone unwilling or unable to analyse the problem, despite having worked on other types of CSP system before.

Further the comment :

Perhaps there are diesel heaters to top up the oil temp on bad insolation days and months. Remember, 25% of energy sent out from one large 12/7 solar thermal operation was found to be diesel powered discussed above

betrays the fact singletonengineer either hasn’t read or hasn’t understood that the particular installations we are discussing use permanently molten salt, not hot oil, and use no gas whatsoever.

As a service to the rest of the readers here, singletonengineer should go back and read the technology documents on the Solar Reserve site properly before posting irrelevant FUD on the Crescent Dunes, Redstone or Copiapó CSP installations.

If the required capacity factor is specified as “direct sunlight hours per year x 2 / 8760” then that allows the system to be configured for the shortest day of the year on the assumption that the sun shines all that day. The inclusion of the capacity factor in the requirements and contract then takes care of the fact that the sun has a known probability of not shining at any particular daytime time.

By varying the capacity of the following high-level components :

x solar PV panels
x heliostats
x solar collectors
x hot and cold salt tanks
x hot salt to steam boilers
x steam turbines and generators

you can configure a system which, with no interuption to daytime sunlight on a particular day, will allow 24 hours generation of the required output subject to no equipment failures. And if it will do that for the shortest day each year then it will do it for any other day.

In addition there needs to be a financial optimisation of the ratio of solar PV generation to CSP generation to minimise the cost to the customer. Only some components are affected.

Thus the specification of a capacity factor related to the number of direct sunlight hours per year allows the design of a baseload hybrid solar system.

About the only valid point singletonengineer makes is that some allowance must be made for component failures, either in the contractual requirements or by providing redundancy in various components.

Accepting sales blurb at face value isn’t engineering. It is intellectually lazy consumerism.

However, contracted PPA’s for a system are an entirely different matter as the supplier is then on the hook for the performance of the system. singeltonengineer confuses the two.

Let’s have some logical analysis around here instead of a refusal to properly understand renewable technologies competing with nuclear. The mantra “nuclear good, renewables bad” is not an acceptable substitute for an open mind.


(direct sunlight hours / year) x 2 / 8760= 12X365X2/8760=4380X2/8760=
8760/8760=1 =100% capacity factor

That requires a whole week’s worth of energy storage because energy from the longest, sunniest day must be stored for about 6 months to the shortest, cloudiest day. And besides that, it requires zero failures, so build 2 or 3 identical complete systems so that down time does not affect output. Then hire an army to defend it and the transmission line. A few divisions of US troops should be enough if they are authorized to shoot anything that comes within 20 miles.

It is obvious without further computation that this would be the most expensive electricity ever delivered.


The question was not Solar Reserve anything… it was about Ivanpah’s results. That was before the wild goose chase.

The answers, to all questions, depend only on verifiable facts, not motherhood statements made in sales presentations.

Thus far, every single solar thermal project in the world of which I am aware of published results has failed to meet the objective of 24/7/365 availability or any specific capacity factor independently of external support, eg through gas, diesel on site, or reliance on grid-supplied power to get through the night, let alone to get through a cloudy week.

Ivanpah was disappointing in that the CEO stated up front that it is set up for a 12 hour day, despite public reports of 25% energy inputs not from the sun but from a gas pipe.

Spanish experience has been discussed here several times, both on the mainland and off shore in the Canaries. Again, not 24/7 and certainly not for a week. Not the holy grail of carbon-free, reliable, available, consistent energy from the sun.

Moroccan dreams of non-existent Saharan solar power exported via future HVDC cables to European customers are yet to eventuate.

If reports of sucessful 24/7 solar-only demonstration plant or full scale commercial applications are available, where are they? Until I see the evidence, I will remain unconvinced.

The question is “Given the recent disclosure of grossly excessive gas consumption by Ivanpah and its stated goal of achieving only 24/7 performance, and then only during favourable weather, where, when and how has solar-only ever worked 24/7, independently of weather conditions?”

Note that compliance with an unpublished PPA is not an answer to the question.

Only one person on this site has stated “Nuclear good, solar bad”. It is not my position, which is to respond effectively to the challenges of climate change. I am an agnostic when it comes to energy options. Cost, timing and performance are the primary criteria.

Please stop putting your words into my mouth.


No person on this site has stated “Nuclear good, solar bad”. All of us who said “Nuclear is the correct answer” did so by solving the math, not by being emotional.

Reference: “Rescue Mission: Freeing Young Recruits from the Grip of ISIS”
A similar de-programming using emotion might be the way to go to get the renewable fanatics to stop being wrapped around an emotional axle. They may have been scared witless about nuclear during childhood.



The success of failure of Ivanpah, which we both agree is unlikely to be a commercial or technical success or replicated elsewhere, is a “red herring” as far as the success or otherwise of any other CSP technology is concerned.

We shall see in the next few months whether Crescent Dunes can meet its contracted service levels. It has already generated full daily output. The service level information is not likely to be in the form of an independent technical report – same as the fact that Ivanpah’s problems and excess use of gas in the mornings came in the form of press reports and not an independent technical report. Such a requirement from you could best be categorised as an “impossible expectation”.

If Crescent Dunes does meet its service levels then there is no technical reason why Redstone and Copiapó should not meet theirs too. Even though Crescent Dunes is not configured for 24 hour operation it is effectively the test case for whether solar tower CSP can act as baseload power in the sub-tropical deserts.


A check of Wikipedia and news resources shows that the first stage of the solar thermal project in Morocco is now producing, lessening the dependence on imported fossil fuels. I believe that the entire project will have little impact on imported power from Spain via an AC link under the Straits of Gibraltar. Nobody, not even DesertTec is proposing an HVDC link there.

Telling, however, is that the rail link being building by Alstom will be powered by a CCGT. See the Wikipedia page on renewable resources in Morocco.


I note that the Crescent Dunes solar power project receives a PPA of US$135/MWh. That is close to the value for the EPR proposed for England. So if that is the PPA for a similar solar thermal project in Morocco there is nothing left for the assumed US$20/MWh to wheel the power to Britain.


The current wholesale electricity prices on the Iberian Peninsula is around US$57/MWh so don’t expect much rush to import from Morroco.


Peter Davies — Do not accuse of cherry picking until you are at least half as good a statiscian as Grant Foster, who runs his Open Mind blog as Tamino. In particular, 2015 was simply the most recent full year for the USA capacity average. Indeed, looking at the graphic you posted from EIA, one sees that the US nuclear power fleet has obtained around 90% capacity since the year 2000.

I assume that this growth to maturity is partly a learning curve for these LWRs and partly a matter of preferring nuclear over coal more recently.

As for the British capacity averages I am not well informed of the British regulatory environment nor how British utilities choose to run their equipment. I have enough difficulty with just the USA. Possibly you would care to learn more about how it is done in Britain and, thoughtfully, inform us. Every country is different.


Kevin Trenberth is not Tamino? I would like to tell Tamino that at CMU in 1965, the physics department really did teach probability and statistics with a laboratory that mimicked historical physics research.


At the foot of this comment is a sobering link from my own country. Solar thermal has been an expensive. well-funded, dismal flop and I have been a small part of it.

Many hundreds of millions of dollars, primarily public dollars, have been spent trying to get solar thermal to work, either in support of existing coal fired power stations in NSW and Qld, or otherwise, globally. Come on, Peter, prove me wrong. I can take it, but can you accept your own fallibility? You cannot, because if you could, you would have ended this discussion a week or two ago by either withdrawing or providing independ evidence of at least one successful solar thermal project, anywhere. But you cannot. You have failed to demonstrate that your opinions are evidence-based, that they are rational.

Peter, please accept that I am not accusing you of being a fool, but of being misguided. I am absolutely sure that you are convinced that your faith in unproven solar thermal (and other?) technologies is firmly founded. Faith is not enough. Evidence is essential.

Remember that David Mills, one of the fathers of solar thermal, eventually sold his patents, corporation and knowledge to a French energy company that abandoned solar in favour of nuclear. David Mills’s life’s work is dust.

History is not on your side, Peter.

Here is the link I referred to above.

Please return when you have the facts to substantiate your claims.


Singleton Engineer,

What a joke eh? Ad we could add so many more examples. Solar thermal started life over 100 years ago and still provides 0.0% of global energy (rounded up).

Whitecliffs solar thermal started with enormous subsides in the 1970,s ran for a few years and was then shut down. The town was connected to the grid. Since then they’ve tired to save face by refurbishing it as a PV station. It’s still next to useless.

And consider Ivanpah at $19/W average power based on the expected output, but it’s actually getting nowhere near it’s expected output.

And of course the recent bankruptcy of Solyandra.

And Abengoa’s collapse.

No end to the example of solar failure


Didn’t there used to be a collection of posts from years ago which detailed the limitations of wind and solar, showing why they can only be a supplement to other energy sources, rather than the major energy supplies for humanity?

Were there not also a series of posts on how the anti-nuclear talking points don’t stand up to scrutiny?

Can the links to those be restored, so I can point the curious to them?
The articles are still there. Use the headings on the left of the page to access all the posts on a topic e.g. click on Renewables for posts on that subject.Use the Search box in the top right hand corner for the relevant subject e.g EROI of Wind. You can also scroll down to the bottom of any page, where you will find a grey button directing you to Older Posts/ Newer posts. There is also a brown button (difficult to see) at the bottom of some pages, which directs to older posts. I hope that helps.


Jim – finding limitations of wind etc – Try searching for “Guest post by John Morgan” in your browser, which I find easier than searching BNC.


Hi, Jim Baerg.

I’m no expert at navigating this site, but the easy stuff works OK for me.

Method 1. At the upper left corner of this web page is a tab marked “Renewables”. This links to several current articles on renewables.

Method 2A. More extensive searching can be done from the search tab, also at the upper left corner. Enter “renewables” and press the space bar.

Method 2B. Alternatively, from your browser, enter

Older articles might be available deeper down, but the ones found via either of the two methods above will satisfy all but the most demanding reader with plenty of time to spare.

Thanks for posting that information. I will add that at the bottom of the page you will find a grey button directing you to Older Posts/ Newer posts. There is also a brown button (difficult to see) at the bottom of some pages, which directs to older posts..


Here’s another article for Jim Baerg and others interested in comparative costs and performance of electricity technologies including renewables.

More analysis from Ed Hoskins, a true polymath with backgrounds in dentistry, architecture, town planning and much more. I very much hope that I will still have a little of Jim’s energy, knowledge and insight when I, too, reach 75.

The original article is at

Ed takes a broad look at the current and projected cost of renewable energy in Europe, focussed primarily on comparison with gas.

The article is repeated on Euan Mearn’s site, where the comments stream is much stronger and hence deeper and more interesting.

Peter Davies and others who choose only to read the comics section of the daily news will be disappointed to find that Ed’s writing consists of words and numbers and monetary values.


Seaweed farming to the rescue.
At least if we washed it in fresh water, we would have abundant fertiliser and solve ‘peak phosphorus’ a hundred years before it threatened us. But how would we store it? Biocharing it would see some of it leak back into the atmosphere in a few decades, some stay for hundreds of years, and some thousands. But my real interest would be how much more carbon would be stored in the soil if this was a regular top up to our farm soils, other than just the biochar. I remember reading somewhere that biochar forms a home for micro-fungi to grow in, much like coral does in its symbiotic relationships. I can’t find the quote, but I read that the biochar itself only stores a fraction of the carbon: it’s the potential fungi that really gets climatologists interested. But that assumes we can keep those farmlands alive, and that the world’s chaotic climate doesn’t burn those farmlands to dust and undo all this sea-weed, biocharring business anyway.
It seems the Climate Council will write about anything other than nuclear. Oh well. We’re stuffed.



blockquote>Although some uncertainties can not be avoid, our estimations for the global potential of solar electrical power are 1,75-4,5 TWe, which implies a hard techno-ecological of solar power potential, much lesser than other assessments.

The present primary power consumption is 16TW (EIA, 2009); although energy efficiency and the quality of renewable resources could improve over time with respect to non-renewable energies, the expected increases in population and per capita energy
consumption mean that the demand for renewable energy, overall, may well exceed 10 electric TW (=10TWe) at the end of this century. Thus, for instance, Nakicenovick et al.1998, forecast global needs of primary energy of 25-65 TW (for 2100), Nakicenovick et al. 2000, 26-42 TW (for 2050), EIA 2010 roughly 24 TW (for 2035), Schindler and Zittel (2007) more than 25TW with 16TWe from renewables for 2100, and Jacobson and Delucchi (2011) believe that 11.5TWe is possible for 2030 from renewables.



Click to access solar-energy-draft.pdf

That is, the maximum achievable contribution from solar electric power is about 5-10% of projected global primary energy demand in 2050.


From the Engineering ToolBox here are some higher calorific values. The three grades of coal are highly variable by source and I only give a central value.
Lignite, i.e, brown coal: 16300
Bituminous coal: 20000
Anthracite: 33000

Methane: 55530

with units of kJ/kg.

This corrects the wrong explanation of why natural gas, almost all methane, is a superior fuel, as found in a linked article by a polymath in a comment several back.

While correct, these values fail to take into account the fugitive methane which escapes into the atmosphere in the course of mining, refining and distribution. Some hold this is enough to make natgas use worse for global warming than even burning lignite.


Google goes right to the Engineering ToolBox so not paywalled.

Of course you can search for upper calorific values.


In inland, high insolation Australia, renewables are not viable, even with the huge subsidies. It’s cheaper to pay very high prices for diesel and gas than to invest in renewables. In the off-grid and fringe of grid areas in Australia (which consume 6% of Australia’s electricity), only 1% of electricity is supplied by renewables.

Only 2 per cent of Australia’s population live in
off-grid areas, however over 6 per cent of the
country’s total electricity is consumed in off-grid
areas. Around 74 per cent of that electricity is
generated from natural gas and the remainder
is mostly from diesel fuel; making it Australia’s
most expensive electricity due to the underlying
high gas and diesel prices in the remote areas.
However, due to lower levels of coal
generation, the off-grid market has the lowest
average emission intensity of all of Australia’s
electricity markets despite only 1 per cent of
electricity is generated from renewable

Click to access ARENA_RAR-report-20141201.pdf


@David Benson

I note that the Crescent Dunes solar power project receives a PPA of US$135/MWh. That is close to the value for the EPR proposed for England. So if that is the PPA for a similar solar thermal project in Morocco there is nothing left for the assumed US$20/MWh to wheel the power to Britain.

David, your comment above is a little disappointing as you are generally clued up and fairly objective.

Crescent Dunes is the first-of-a-kind commercial project for the Solar Reserve solar tower thermal CP technology, while Hinkley point is the fifth implementation of the EPR. So you should expect that later solar tower thermal project LCOEs (such as that for Copiapó) will have a lower LCOE than Crescent Dunes.

Further, solar tower thermal CSP on its own is not a cheap enough technology for baseload generation. The expectation is that both it and solar PV will get cheaper over time, but that solar tower thermal will always be at least twice the cost of solar PV.

The winning combination for semi-tropical desert baseload is solar PV plus solar tower thermal. During the decent direct sunlight hours cheap solar PV provides power at around half the LCOE of the solar tower CSP. At dawn, dusk and night the higher priced solar thermal hot salt storage solution is used for generation.

Crescent Dunes thus provides only one part of an implied baseload solution. The other part is all the cheap solar panels on the casinos of the Las Vegas Strip generating at an LCOE that is at most half of Crescent Dunes.

Those two pieces of information, not factored into your response above, are why the Copiapó, Atacama Region, Chile hybrid solar project is a better comparison of the strength of hybrid solar vs EPR for baseload generation in sub-tropical regions. And Copiapó is not subsidised either, while Crescent Dunes almost certainly has an ITC subsidy.

Incidentally, the Las Vegas casinos are well capable of affording the higher costs of such a FOAK solar project. The business case probably includes the additional gambling tourists who would visit a fully solar-powered Vegas. So it is most likely a win-win deal for both sides, even at FOAK prices.


@peterlang, @singletonengineer

You guys should look at the faulty logic you are posting on solar thermal.

Edison’s team testing something like 6,000 different materials for the filament of a light bulb before coming up with one that had the necessary lifetime while also suitable for 110v operation. By your logic the final solution was doomed to failure by the history.

Similarly, it does not matter how many historical CSP failures there have been, provided that at least one is a success.

Ivanpah, various Fresnel trough implementations, etc. all appear to have shortcomings. But this says nothing about whether CSP will become a major component of global power generation in suitable locations.

Hybrid solar – solar PV plus solar tower thermal – appears to be in good shape to take the accolade ot me.

So give the irrelevant history a rest, will you, and devote your considerable energies to telling us what aspects of solar tower hot salt thermal + storage you would see as most likely to cause later problems for a system like Crescent Dunes which has already generated successfully but for only a few days. That would be a welcome contribution.


That’s a valid and fair comment, Peter. The energy supply debate has devolved into a super polarised conflict, with a very sharp adversarial divide between pro nuclear and pro renewables advocates. It shouldn’t be that way.

The same accusations can go both ways, with regard to allowing time to prove up viable generation technologies.


You have got the polarization wrong. It is not nuclear vs renewables. It is people who really do have engineering degrees and can do the math vs people who are faking engineering degrees [Peter Davies]. The fakes are easy enough to spot if you do have an engineering or equivalent degree. Peter Davies reasons by metaphor, telling a story about Edison. Edison is irrelevant.

The real renewables vs nuclear: There are cases where wind is the best answer: remote windy places. There are cases where solar is the best answer: small amounts of power needed where connection to a grid is inconvenient. Calculators, marker lights along driveways, spacecraft closer to the sun than Jupiter. For anywhere on the surface of the Earth where megawatts to gigawatts are needed continuously: nuclear is the best answer unless you have hydro. For deep space, beyond Jupiter, nuclear is the only possible answer. All of our spacecraft that have flown to Saturn and beyond use nuclear.


@David Benson


In the earlier posts about HVDC line losses it is worth noting that there is a trade off.

Some of the line losses and quite a bit of the total costs are due to the conversion equipment both ends, and these are fixed.

However the main losses from the length of the line are ohmic. In a picture of the Carbon County line to California, only one pair of conductors was shown. However, I have seen other pictures with two pairs.

So the length-related line losses can be reduced at some cost by providing more than one pair of cables. This additional cost may not be a killer if the cable is not the most expensive component to start with.

This cost may vary quite a bit with time too, as copper commodity prices seem to be rather variable.


Re HVDC line losses. Increasing the capacity of a DC line is primarily about increasing the cross-section of the conductor, that is, using two fatter cables. Power cables are conventionally made with an aluminium core and a tensile steel coat, not copper. Increasing the number of cables can be counter-productive with AC lines, as much of the power is carried in the electromagnetic fields around and between the cables. Radiative losses from these fields occur at the points of suspension, where the cables change direction sharply. Radiative losses go up strongly with voltage, hence HVDC is preferred for high power transmission.


I drafted a response to Peter D’s recent comments, but reconsidered it.

The creator of this site has stated several times and I agree with him that (in my words):
1. The threat of climate change is real and challenging, warranting urgent response by all available means.
2. Nuclear energy will of necessity be a factor in meeting the challenges of climate change and of providing energy to a world which is energy-constrained (at least, for the poorer few billions of humans) and which has widespread heavily polluted and damaging atmospheric pollution due primarily to use of fossil fuels.
3. Discussion should be evidence-based, with references cited.

It is pointless continuing a discussion with one who, though entirely unable to substantiate his opinions persists in asserting them in a series of rants.

Real engineers and, indeed, professional in any discipline, base their expectations for future performance on the documented history of past performance. Anything less than this amounts to an appeal based on faith and optimism.

Visions of a solar-only electricity future, such as endlessly advocated by Peter Davies, are currently not based on historical successes, because the available data indicates that there not one instance of successful solar thermal power generation, anywhere in the world – not on an island, not in a desert, not in a rich country with the best brains and best technology.

Many may share my hopes for future improvement, but Desertec, Ivanpah and all the rest are nowhere near sufficient justification for rational professionals to recommend that nuclear power options can be set aside in favour of a solar thermal future, with or without combinations of solar PV and a global HVDC grid.

The best that can be said at this stage is “It is too early to know.”


Comment 1000 in Open Thread 23.

Peter Davies — I agree with the EDF engineers in that the EPR needs some redesign. I will go further to state that Britain would be better off by acquiring about 40 of the Nuscale modules instead. Then the average wholesale price ought to be about US$90/MWh. If this were done the wheeling of power from Morroco becomes even less attractive.

As a rough estimate, suppose Moroccan solar PV is but US$30/MWh for 8 hours per day; given the isolation curve that seems generously low but let’s try it. Solar thermal at US$135/MWh does the rest, with 8 hours overnight only 70% as much required. So for 24 hours, per daylight MW equivalent, generators require

830+(16+80.7)*135=3156 US dollars

for an a average of 131.5 US dollars per normalized MWh. So after adding in the cost of wheeling the power to Britain it’s still much more expensive than the proposed EPR. Not to mention the technical and political risks associated with wheeling across two water barriers and through two foreign countries; for example, someone might do to transmission towers what recently occurred in southern Ukraine.


Edison’s lightbulb may have taken thousands of iterations to get right. As the world’s first inventor of an electric lightbulb, he had that time! We don’t. Peter Davies wants us to click our ruby slippers together 3 times and just BELIEVE that some magical new solar thermal materials will lower prices and provide a magical synergy with Solar PV. Peter, we don’t have time to wait and see. We have to COMMIT. NOW. To something we KNOW works from DECADES of experience.

YOU quote solar thermal and pixie dust and sheer belief?

WE quote France’s Gen2 reactors that have safely provided decades of baseload reliable power no matter the time of day, season of year, or mood of the weather. We can do this, but only if pixie dusters like yourself get out of the way, support nuclear power whole-heartedly, and maybe add the by-line that we can always move back to solar thermal if the pixie dust belief finally bears fruit some decades in the future.

I am not against renewables. I’m against inaction based on vague assumptions and really cheesy metaphors. Edison isn’t the right metaphor. Winston Churchill warning the British people about Adolf Hitler before the war is!


DBB: Various risk loadings should be added to your figures in respect of:
1. Technological risk – undemonstrated technology at that scale.
2. Political risks (spanning 4 or more countries, some of which have been known to get somewhat uptight from time to time), 3. Sovereign risk (only one government needs to back out and there is a major event),
4. Currency risk (at least three currencies involved, probably also funding via $US, so perhaps 4 or more).

Plus risks due to the vagaries of weather, regardless of the amount of molten salt, etc.

The project risk profile of nuclear is looking pretty smart in comparison.


singletonengineer — Yup. Even the EPR looks much better.

However, another possibility is just solar PV with resistance heaters into thermal stores. When supercritical carbon dioxide Brayton cycle turbines become available a rough estimate becomes about US$65/MWh at the generators busbars. While good, that isn’t even good enough to compete via wheeling from Morroco just to Spain where the associated risks you mention are much smaller.


Peter Davies, as an engineer, how can you say “give the irrelevant history a rest” when discussing mass deployment of expensive, unproven technology (CSP in this case)?

Surely your training focussed on delivering practical systems at economically sensible costs so that resources (including money/finance) are not wasted.

Your line of thinking would have had Edison force people to buy light bulbs that burnt out every few hours of operation rather than test the 6000 odd materials and configurations before putting a durable and economically viable light bulb on sale (and letting market forces determine its success).

Or should people have been forced to abandon gas, oil and kerosene lamps and returned to candles when Edison first started his light bulb experiments in expectation that he would come up with a solution in short order?

Engineering is about solutions. If the problem to be solved is for a critical requirement, then the solution should be proven, not experimental. .


Let’s examine critically the words used by singleton engineer to represent the views of the owner of this site.

1. The threat of climate change is real and challenging, warranting urgent response by all available means.

I agree with this. We should be considering all available means. That includes solar PV, solar CSP, wind, tidal, nuclear, geothermal, hydro, CCS and a few other technologies. China’s approach is good – install as much of all proven low carbon technology generation as fast as possible.

The EPR at Hinkley point was originally supposed to be generating by the end of 2017.

French nuclear energy giant EDF says it hopes to build Britain’s first new nuclear power plant in a generation in time to provide electricity for Britons to cook their Christmas turkeys in 2017. “EDF will turn on its first nuclear plant in Britain before Christmas 2017 because it will be the right time,” Vincent de Rivaz, chief executive of UK division EDF Energy says. “It is the moment of the power crunch. Without it the lights will go out.”

NuScale is not expected to be in production until 2023-2025 either.

So what happened to the bit about “warranting urgent response”?

Hands up who thinks no new generation operational in the next 7 years is a satisfactory “urgent response” for UK or anyone else?

Or are the words a coded message meaning “as fast as possible subject to the availability of new generations of nuclear”?

<2. Nuclear energy will of necessity be a factor in meeting the challenges of climate change and of providing energy to a world which is energy-constrained (at least, for the poorer few billions of humans) and which has widespread heavily polluted and damaging atmospheric pollution due primarily to use of fossil fuels.

In my opinion nuclear should indeed be a factor. But not the only factor.

And, let’s face it, nuclear has blotted its copybook with the majority of voters in a few significant countries, and there is a very strong probability nuclear will not be a factor in any of those. Further, none of them appear to have any serious misgivings about being able to eliminate all CO2 emissions. So it is critical not to dismiss the alternatives to nuclear.

3. Discussion should be evidence-based, with references cited.

Singletonengineer would insist on an independent technical audit which can only start AFTER live operation (of a solar tower thermal CSP plant) before any claims are made that the technology looks very promising.

Has he ever suggested this same level of evidence is necessary for the EPR or NuScale? If so, then perhaps he would be kind enough to provide a link.


Peter Davies asked about speed? When national governments get behind nuclear programs instead of bowing to every little greenie protest, amazing things can happen. Why do you cherrypick nuclear build out speeds from the most notoriously slow projects on the planet? Are you cherrypicking history as badly as you (apparently according to engineers here) cherrypick CSP performance as well?

“As a direct result of the 1973 oil crisis, on 6 March 1974 Prime Minister Pierre Messmer unexpectedly announced what became known as the ‘Messmer Plan’, a huge nuclear power program aimed at generating all of France’s electricity from nuclear power.[15] At the time of the oil crisis most of France’s electricity came from foreign oil. Nuclear power allowed France to compensate for its lack of indigenous energy resources by applying its strengths in heavy engineering.[18][19] The situation was summarized in a slogan: “In France, we do not have oil, but we have ideas.”[20] …. Work on the first three plants, atTricastin,Gravelines, andDampierrestarted the same year[15]and France installed 56 reactors over the next 15 years.[23]”
France now has some of the cleanest electricity in Europe and is the world’s largest exporter of electricity.


Re Peter Davies’s latest:

If there is a suggestion that I have argued against renewables or pro-nuclear per se, then where and when did I make it? I have not. I am technology-neutral, but that isn’t sufficient for those who pretend not to be biased while displaying extreme prejudice against one or more energy options.
Ben Heard, who is much more erudite than I am, recently presented a video about how we can build our energy future. It is very much worth viewing. It was delivered to a forum dominated by nuclear power representatives but applies equally to all players in the game who seek productive discourse rather than mutual chucking of verbal hand grenades between opposing fortified positions.


View it!

From one who publicly holds a biased single personal objective close to his heart, it is incongruous to read:

“We should be considering all available means. That includes solar PV, solar CSP, wind, tidal, nuclear, geothermal, hydro, CCS and a few other technologies.”

Those fine assertions are not believable in the context of their author’s previous writings on this thread. His diversionary scattergun “look over there” approach to rebuttal, his incessant sidetracking and childish attempts to redefine the discussion when challenged, backed continually by a stream of unreferenced assertions are not alternatives to demonstration of facts.

Isn’t it past time that this conversation followed Ben’s advice about creating our futures?


Peter Davis, you are keen on speculating on advances in technology that will make CSP much more economically viable.

From my perspective, CSP is a very mature technology that has hit its limits and can only improve in an incremental sense.
Mirrors – reflectivity, focus and tracking are close to theoretical perfection (providing the mirrors are kept clean).
Thermal Receivers – I have no idea here as I cannot find any information
Generation Efficiency – limited by thermal differential (Rankine cycle)
Storage cycle efficiency – limited by heat loss rate which gets worse as the thermal differential is increased

Are you willing to speculate on what areas these advances may lie? Of these, which would not improve other forms of thermal power generation by the same degree?


Greg Kaan, I can think of five ways that CSP could be made significantly more economically viable:

The cost could be substantially reduced if all the components are mass produced.

How many people are needed to operate it? Are the mirrors self cleaning?

Is it optimised to meet electricity needs at the times when electricity wholesale prices are at their highest?

The thing that could make the most difference to profitability is the interest rate that the money to build it is borrowed at. Something that would fail to cover its costs at 8% could be very lucrative at 2%.

Could it be colocated with thermochemical plants so that the heat it produces could be used for more than just generating electricity? Could it be colocated with solid oxide fuel cells (which are very efficient but require a high temperature to operate) to generate electricity from methane when it’s not sunny?


@David Benson

(8)(30)+(16+(8)(0.7))*135=3156 US dollars

David, your intended scenario is unclear. The formula for working out the average PPA cost per MWh for a combination of solar PV and CSP for Las Vegas would be :

((Cost/MWh(PV) x PV equivalent full hours) + (cost/MWh(CSP) x CSP equivalent full hours)) / total equivalent full hours.

Assume a scenario as follows :-

x – 8 hours / day PV at full load (total 8 equiv full hours)
x – 4 hours / day CSP at full load (total 4 equiv full hours)
x – 12 hours / day CSP at 70% load (total 8.4 equiv full hours)

PV equivalent full hours is 8
CSP equivalent full hours is 4 + 8.4 = 12.4
Total equivalent full hours is 8+4+8.4=20.4.

Average cost / MWh is :-

(($30 x 8) + ($135 x 12.4)) / 20.4 = $94 / MWh average.

Your $30/MWh is rather too low for current PV. Between $40 and $50 would be better – say $45. $135 / MWh is too high for the CSP based on Crescent Dunes prices, for a subtle reason.

Crescent Dunes is configured to generate for 10 hours at the given output (or 10 full equivalent hours). In the assumptions above CSP is generating for 12.4 full equivalent hours. To go up from 10 up to 12.4 hours we need to configure 25% (rounding up 24% for easier maths) more heliostats, solar collectors and hot salt storage, but no more hot salt to steam boilers, turbines and generators. There is 25% higher load factor for these back-end components and more revenue from the price / MWH. So per unit generated the scenario above needs only 80% of the capital on the hot salt to steam boilers, turbines and generators compared with Crescent Dunes. So our price / MWh comes down because of the increased back-end equipment load factor.

I don’t actually know what fraction of the Crescent Dunes capital cost the back-end represents. The simplest guess is 50%. Then the cost for the 12.4 equiv full hours (vs 10) is 90% of the Crescent Dunes capital, and therefore the PPA cost becomes $121.5/MWh.

Redoing the calculations above :

Average cost / MWh is :

(($45 x 8) + ($121.5 x 12.4))/20.4 = $91.5/MWh

There’s still a US ITC subsidy in both the PV and CSP prices and therefore average price quoted above which never gets included in PPA prices. It’s just hte way they do it in the USA. Nuclear may also get some subsidy in the USA. The expectation is that utility-scale PV solar will drop enough in price in the next 2-3 years to cover the ITC subsidy.

The CSP prices above are based on FOAK solar tower thermal at Crescent Dunes, so this will come down too for subsequent implementations. The NuScale claim for the next few reactors after the first is for a 10% reduction, so that would seem like a good assumption for the next few Crescent Dunes technology CSP installations too.


@Greg Khan

Peter Davis, you are keen on speculating on advances in technology that will make CSP much more economically viable.

There will doubtless be some advances in the technology. But there’s no need to bank on it.

One reason for prices coming down for a product is purely increased volume. That has applied to solar PV and wind turbines. The metric usually used is a percentage reduction in price per doubling of volume installed.


The usual expectation is that the reduction in price per doubling of volume is in the range of 10-25%.

Sure, technological improvements would be nice, but not necessary just to achieve price reductions.



p.s. Here’s one thing I forgot about which is a direct answer to your question.

Solar Reserve has been given a grant by the US DoE to improve their solar collector

In September, ­SolarReserve won a US $2.4 million grant from the U.S. Department of Energy to develop a ceramic receiver that can withstand 732 °C.

The current maximum temperature of operation is 566 °C. Operation at the higher temperature would enable a higher thermodynamic efficiency, which would reduce costs. The theoretical efficiency improves from about 64% to over 70%, which could mean up to a 10% gain in efficiency and a similar reduction in prices.

Whether the higher temperatures are possible and actually provide this increase in efficiency remains to be seen, but the potential is certainly there.


Hi Peter,
I note you didn’t reply on speed of nuclear deployment? In case my wikipedia reference didn’t help, here is Dr James Hansen on the need for nuclear, then the speedof deployment.

“Can renewable energies provide all of society’s energy needs in the foreseeable future? It is conceivable in a few places, such as New Zealand and Norway. But suggesting that renewables will let us phase rapidly off fossil fuels in the United States, China, India, or the world as a whole is almost the equivalent of believing in the Easter Bunny and Tooth Fairy.”

According to Hansen we should build “115 reactors per year to 2050 to entirely decarbonise the global electricity system” which, on a reactors per unit GDP level, is actually slower than the rate at which the French already cleaned up their electricity in the 70’s.
In other words, there’s nothing hypothetical about 115 reactors a year because France has already deployed nuclear faster than this rate per unit GDP!


“115 reactors per year to 2050″ Well, we can take it that Hansen meant “115 GW per year through 2050”. Mass-produced reactors are likely to be a lot smaller than 1 GW apiece. But mass-produced SMRs can be made to achieve the same rate. Must be, once the global will to do so surfaces.


@Aidan Stainger:
I am able to address several points from personal experience but not to provide full references due to conditions of past engagement.

“The cost could be substantially reduced if all the components are mass produced.”
Great advances have been made by at least one German designer/constructor using automated approaches, robots and techniques from the auto manufacture sector. Materials, equipment and key staff were transported from Germany to the Hunter Valley in NSW, where a factory was established in leased premises. There was no welding. Components were crimped together. Quickly and elegantly, accurate light mirror assemblies were produced and stacked on pallets without human touch.
In the field the arrays were mounted on very light steel earth screws which were located to sub-milimetre precision using semiautomated techniques and laser alignment at a phenomenal speed. No concrete was used except for the anchor blocks of the steam mains and the footings of the control room.

Of course, there are welded components in the towers that support the collector (steam) tubes, but even they were very light weight and elegant in comparison to earlier installations by other designers.

“How many people are needed to operate it? Are the mirrors self cleaning?”

Why water at all? Semi-automatic mechanical cleaning of linear fresnel arrays was a feature of the above collector field.

Water can be a problem for many reasons – scarcity in dry climates, pumping and pipelines, weight, resulting muddy puddles on site and so forth.

Unfortunately, I understand that the completed work is not a commercial success and, several years afterwards, still has great operational limitations, but Aidan is correct: Design and operation of solar thermal collector arrays is evolving.

The arrays I was involved with supply steam to an existing coal fired power station, thus reducing coal usage. I have no hands-on experience of thermal storage using molten salt.


Why would any rational, objective, informed person still be trying to argue that solar thermal is viable, or potentially viable. Solar thermal engines have been around for over 100 years and going nowhere. RE advocates were saying in the early 1990’s “solar thermal is baseload capable and cheaper then nuclear now, if the stupid government would just give us more money to demonstrate it”. Some are still preaching the same nonsense.

Ivanpah: $19/W average power based on expected generation. However, the actual generation is much less than expected and it’s using much more gas than expected. It’s another example of the CST fiasco.


@Peter Davies:

Peter assumed that Crescent Dunes can/will supply 4 + (12 x 0.7) = 12.4 hours full load equivalent of electricity on a daily basis.

Without a technical reference, it is not possible to determine whether the production figures and hence the unit costs of power produced may be based, for example, on much lower storage requirements and collector proportions than necessary and thus be out of whack.

Further, as many times stated on this thread and elsewhere, any assumption that electricity will be available continuously irrespective of weather, either requires extreme volumes of molten salt storage or includes an assumption of back-up, eg as experienced elsewhere by use of fossil fuel support for heating, reported as being equal to 25% of ESO in one instance.

Peter’s costs also do not include an allowance for downtime when the market is low – already some wind is needed to be “spilled” when demand is low and this is causing ongoing commercial dramas, eg in Germany, where the wind generation owners seek payment at the same (subsidised and thus inflated) rates as they would have received had they not been directed to spill their surplus capacity.

In many networks, this happens only after other, typically nuclear and coal, conventional plants have been required to reduce load to follow demand downwards.

In a primarily renewables market, there will be no other supplier to suffer these costs. There is a significant probability that the formerly protected wind, PV and STP sources will have to back off for a percentage of the time – at a rough guess, perhaps 30% would be an appropriate sensitivity figure to look at (See more below.).

Similarly, there will need to be spinning reserve and other reserve plant available… again, plant operating at reduced load or available but not in service on sunny days, entirely due to the need to maintain reliability against failure due to demand changes or unscheduled loss of load from a generation source.

I have spent decades working with larger 500MVA or 660MV coal fired plant, most of the time with a scenario such as:
8 Units total.
4 In service at 80% to 100% load all day.
2 In service at lower levels – typically the smaller and less thermally efficient ones.
1 Available on standby.
1 Undergoing maintenance or otherwise withrawn from service, awaiting market conditions when it can be bid back in.

That was in the good years.
In lean years, eg the past decade, 4/2/1/1 ismore likely to become 3/2/2/1.

Peter’s STP will not achieve its hoped for 12.4 hours full load operation over a full year. For various reasons, its capacity factor will lie well below the assumed 51.67% and he should expect something close to 70% of his anticipated loads, ie a capacity factor of 36% at best.

If operating costs are constant and the cost of capital is the only significant other cost, there can be no appreciable load-related savings. Whatever unit production costs Peter adopts will increase correspondingly in relation to that 70% (or whatever) CF adjustment in the real world.

So, dividing Peter’s guesstimate rate of $91.7 by (1 – 0.7) => $130.71 per MWh at the busbar.

To that figure of $130.71 must be added whatever is required to overbuild the plant to achieve the following:
… Winter energy performance that will achieve the nameplate rating;
… Reserve heat storage for poor insolation conditions;
… Increased collector capacity to replenish the thermal stores in advance of cycles of poor weather;
… Allowance for reducing plant performance as it ages.

After adjustment to suit the real world, $200 per MWh seems to be much closer to the number. What does that do to market expectations?

Australian NEM at the busbar have averaged around $AU50 to $AU60 in the past decade. At, say, $US 0.75/$AU, that converts to $US45.00 tops on the income side.

That, of course, is before allowing for upgraded super-long HVDC interconnection, which has to be paid for somehow.

I doubt that the comparison figure of $US200/MWh will increase greatly. But who cares if it is $US300? It’s only somebody else’s money, after all. Besides which, It won’t ever be constructed, so we are really only discussing hypothetical plant, markets and transmission systems.

The takeaway message is just how misleading calculated costs can be unless they actually allow for everything, including financing costs, land cost, overnight construction cost, operating costs, maintenance, shareholder profits and all risks, as well as matching the engineering to the assumptions relating to production/output.

Liddell Power Station, 2000MWe, has operated since 1971. Its best ever annual production was 11,586 GWH in calendar 2009 (With zero lost time injuries, I might add). This is a thermal power station with constantly available, not weather-dependent, energy input in the form of coal. Its CF for its best year out of 45 was 66.13%.

That, my friends, is an absolute upper bound of expectations for a thermal (including generously proportioned STP) power generating plant in the real world. Certainly not even close to $US91.7

Peter’s prognostications are out by a factor of three.


Sadly, I think every time the engineers here engage Peter Davies on CSP numbers, he sees it as an invitation to keep dreaming and trolling and ‘believing in’ CSP unrealities. Sadly, as Hansen said, he’s in the realm of the Tooth Fairy and Easter Bunny.


Thanks, Eclipse Now. You are correct, except that it is more than engineers that are out of step with Peter Davies. Geologists, physicists, mathematicians, economists and statisticians would all take issue with his arguments.

Those posting here, in the main, have tried to explain and to reason and have gone to great lengths to do so. One so-called electrical engineer has decided to adopt a policy that unreliables including CSP and though never demonstrated to be reliable, economical and affordable at grid scale are Good and that nuclear power, though demonstrated in practice to be safer, environmentally more sound, lower cost and to have lower ground level footprints than alternatives is Bad. He has embarked on a one person, irrational, unreferenced anti-nuclear fight against reality. His preferred sources of information are unreviewed, information-free spruiker’s claims as to what might someday be possible in an imagined future. Like a good preacher, he much prefers to tell stories than to listen to otrhers. He chooses to operate from a pulpit of his own choice, with his own vesion of reality.

The majority here have offered tutorials as to how to avoid adolescent, fact-free intervarsity debating styles and instead to adopt fruitful, reasoned and rational discussion. We have all failed. You, me and PD. We have wasted our time.

One thing I am certain about: PD might be, as he claimed a week back, a university-qualified graduate engineer, retired after a career with IBM. Graduate engineer he might be, but certainly not a professional engineer. Professional have ethical standards.


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