Guest Post by Martin Nicholson. Martin studied mathematics, engineering and electrical sciences at Cambridge University in the UK and graduated with a Masters degree in 1974. He published a peer-reviewed book on low-carbon energy systems in 2012: The Power Makers’ Challenge: and the need for Fission Energy
Firstly, what does renewable energy (RE) actually mean? Wikipedia says renewable energy refers to the provision of energy via renewable resources which are naturally replenished as fast as being used. RE resources include sunlight, wind, biomass, rain, tides, waves and geothermal heat.
In “The myth of renewable energy” (Dawn Stover, published in the Bulletin of the Atomic Scientists), Stover believes that “renewable energy” is a meaningless term with no established standards.
RE certainly needs to deliver energy that we can readily use – more than just the RE resources (sunlight, wind, etc.). These RE resources have to be converted into usable energy. We need wind turbines, solar panels, farming equipment and generators for biomass, and water catchment and generators for hydro sources. Alas wind turbines and solar panels do not grow on trees.
Renewable energy converters require the use of steel, copper, concrete and rare earth elements plus all the land on which to build these converters. Wind farms and large scale solar plants require transmission lines to connect to the electricity grid. The materials used to make the energy converters and transmission lines are not naturally replenished so Stover is probably correct when she says “renewable energy” is a meaningless term. But let’s stick with the term for now because it is in the common vernacular.
But is RE looking like a ‘new religion’?
It certainly seems to have its gurus (definition: “an influential teacher or popular expert.” ). In the USA there is Amory Lovins – Chairman/Chief Scientist of the Rocky Mountain Institute USA and Bill McKibben – Founder of 350.org. In Australia we have Mark Diesendorf from the University of N.S.W. All seem convinced that 100% RE is the ultimate target for the future to replace all fossil fuel energy sources.
RE even has its own institutions, creeds and denominations, in the guise of Greenpeace, The Sierra Club, the Rocky Mountain Institute and 350.org, among many others. RE bibles have even been published such as Greenpeace’s Energy [R]evolution. Alas the sermons often contain a good dose of greenwashing.
But the RE religion also has its critics. David MacKay FRS is the Regius Professor of Engineering at the University of Cambridge. MacKay has written a book titled “Sustainable Energy – without the hot air” – available for free at MacKay’s website. More recently, MacKay presented a TEDx talk titled “How the Laws of Physics Constrain Our Sustainable Energy Options”.
In this TEDx talk, MacKay looks at the land use for RE resources. He calculated the power density in watts per sq. metre for wind, solar, water and plants/biomass (see Figure 1). All RE resources are diffuse.
Figure 1 – Power density for various RE resources. Source MacKay TEDx talk 03-2012.
He then compares these power densities to the energy consumption per person and population density for countries around the world (see Figure 2). MacKay tells us that to use RE sources alone, you would need to consider the land use as “country” sized or at least a good part of the country. For example, to power the UK with RE alone would require about 25% of the total land area for the UK.
Figure 2 – Energy consumption and population density. Source MacKay TEDx talk 03-2012.
In comparison, MacKay estimates that the alternative low emission energy source, nuclear power, has a power density of about 1,000 W/m2. But within the RE religion, nuclear power is treated like Mephistopheles: demonised at every turn, despite it being one of the cleanest and safest sources of energy. Why do the 100% RE advocates demonise nuclear power when it has a land use 1/500th of the most efficient RE source?
Gaia has given us many energy sources, but the most land efficient sources are uranium and thorium because of their very high energy density – why are we not using them more often? Perhaps the renewable energy story was too good to be carefully fact-checked.
Don’t get me wrong. I’m not against renewable energy. I’m just concerned that RE devotees, who genuinely believe that we can supply all our energy needs from RE sources alone, consider carefully this excellent work from MacKay which suggests that using RE sources alone will not be the case for most countries. The laws of physics are against it.
Martin Nicholson
End-note from Barry Brook:
Of course, we should always try to be our hardest critics. Can the same be said of those who advocate for nuclear energy?
I would argue not, because in its environmentalist (not fundamentalist) form, a nuclear-friendly advocacy does not seem to meet any of the criteria Martin outlines above for religiosity. In this ‘doctrine’, no energy source is demonised — the argument is instead that all energy sources ought to be weighed fairly on their merits and demerits, on the basis of irreligious laws of nature (and market forces!). Gurus are lacking, at least those dedicated to the creed. Nor are there obvious counterpart advocacy institutions (or perhaps we count the WNA and Ecolo.org?) or bibles (see Loftus et al. 2014 for a review of such global decarbonisation scenarios). But we do definitely have our denominations and bellum sacrum – witness the fast reactor vs thorium schism!
Let’s explore these issues in the comments…
Religiosity is what the IPCC and the science community is repeatedly accused of – by climate change sceptics – so I’d be a little careful in using the term too recklessly. It’s become a term than any group can conveniently fire at another.
That said, even as an advocate of a renewable energy future I accept that for many citizens who don’t have much technical background low density renewable energy is seen as a grand panacea when it clearly isn’t and can’t be.
The religiosity tag is relevant when the hard limits of renewable energy are not recognised or are seriously overblown. What has encouraged this latter train of thought in recent times is 1) the plummeting prices of solar pv and 2) an enthusiastic advocacy of renewable energy on the grounds that the public needs to hear positive stories. What more positive story is there than to keep coal in the ground and run industrial society on solar panels?
That’s a naive prospect that has become an infectious meme. I test this out among environmental advocates and most have a much more measured view. Most couple renewable energy development with the need for tandem radical culture change, recognising that the net energy return on renewables (other than hydro) is much lower than what modern society requires to function in its present form. This is especially so if battery back-up is configured into renewable systems.
Environmental advocates such as Mike Stasse at Damn the Matrix https://damnthematrix.wordpress.com/ represents the opposite end of the renewable energy belief spectrum, not discounting it as a useful energy resource but recognising its cradle-to-grave energy analysis as possibly negative and thus limiting its applicability only to essential needs.
The pivotal philosophical argument is not really about renewable energy it is about the prospect of sustaining growth in a finite world and what happens if (or when) growth stalls.
It doesn’t make sense to call renewable energy a new religion, because it’s part of a package containing:
* environmentalism
* climate change obsession
* renewable energy
RE is much better understood as part of a political project. Like many previous political projects, it doesn’t need to make sense. The trick is to offer something apparently new, while being as imprecise as possible over the practicalities. As CC damns us, RE is the salvation. It’s the fanaticism of the RE believers that draws comparison with religion: their ability to dismiss the usual rules of debate (economics, CBA, practicality, …) on energy matters. All political extremes show similar fanaticism. No one really argues from the evidence in politics; not even mainstream parties.
RE offers something apparently new, it’s the environmentalist’s heaven to their climate change hell. Heaven and hell are just metaphors here.
Barry,
I think the Schism that you are referring to is between the Integral Fast Reactor (IFR) and the Molten Salt Reactor (MSR). Both reactor types can theoretically use Uranium and Thorium.
The point is that the R&D funding provided for these technologies compared to the funding and subsidies given to RE technologies is well short of the promise and potential that they offer.
This lack of funding is a result of the political lobbying of the religious zealots mentioned above just as much as it is from the general populations ignorance of the facts of Nuclear Power.
Students studying Senior Chemistry and Physics will most probably graduate with an almost complete ignorance of Nuclear power because their is nothing in the curriculum and most of the teachers (my daughter included) know nothing about it either.
As an aside
I keep asking my Pro RE acquaitances how do you generate electricity at night with Solar. They have never answered my question.
When I mention nuclear power they become quite irrational and start talking about Bombs and also exhibit all the clinical signs of Radiophobia.
Regards Tony Carden
1.000 W/m2 for nuclear – come on really???
A gigawatt facility is about one square kilometer.
What about the average capacity factor of nuclear power plants should that number not be factored in?
What about the period after decommission should that not be in the equation?
What about the construction period is that not also excluding any other use of the land?
The safety clearance area in terms of habitation, ground water extraction etc. around nuclear installations is how big?
The needed area to provide 2,7 liter water per produced Watt is how big?
The needed area for the mine operation that deliver nuclear fuel is how big or does cooling water mysteriously flow to nuclear power plants?
The needed water resource for mining is how much and how much area does it require to receive the water needed for the operation?
The needed area to produce the nuclear fuel is how big?
The needed area to store fissile waste is how big?
The areas affected by nuclear mishaps are they too excluded from the calculations?
On one side of the equation there seems to be no calculations.
Sure a one gigawatt nuclear power plant delivers 1.000 W/m2 if you ignore anything before after and around that nuclear power plant and assume 100% capacity factor.
As for the other “calculations” that is used to compare I think there is a lot of fuzziness.
Modern wind turbines does not exclude a number of normal activities beneath and around them and the same is true for several other renewable technologies whereof several are simply not mentioned.
The renewable energy density figures are also way too low for especially wind and solar.
If wind only has to be cheaper than Hinckley Point in British context then offshore is a possibility and a modern offshore wind park would claim a tiny fraction of british waters if it were to supply the entire British energy consumption.
Just to avoid being accused of advocating offshore at the bloated price level it has been sold for, I strongly recommend to await lower prices for offshore.
Hornsrev 3, that Vattenfall has won the bid to build currently awaits commission, will get a guaranteed price per produced kWh of 0,77 DKK, which is $0,11 per kWh but only for a ten year period and only when the spot market for electricity is above zero cent. After the 10 year period Hornsrev 3 will sell electricity on the spot market to whatever price the market is prepared to pay. The projected lifetime is 25 years so the average selling price per kWh will most likely be around $0,075 US cent per kWh.
This price is a little less than the current wholesale electricity price in Britain.
But very much cheaper than Hinckley Point.
http://www.theguardian.com/environment/2013/oct/30/hinkley-point-nuclear-power-plant-uk-government-edf-underwrite
In reply to Jens Stubbe
The Math is quite simple.
A. 1 gwhr = 1000,000,000 whr (one billion)
B. 1sqklm =1,000,000 Sqm
A/B = 1000whr/sqm
If you doubt the figures I suggest you follow the link to the TED talk the Figures are Prof McKays.
The proposed Gen 4 nuclear reactors such as IFR’s and MSR’s do not use water as part of the process unlike the current reactors.
Thorium is currently available in significant quantities as a byproduct of Rare Earth Mining. The Chinese have plenty.
The current estimate is that one tonne of thorium can provide the same amount of energy as 3.5 million tons of Coal
Regards Tony Carden
I suppose that I’m not really that different then “them” (i.e. the renewable energy advocates or renwaphiles as I like to think of them). I care about preserving genetic diversity, and climate change. I also care about human beings and that people now and in the future should get to lead some kind of decent life with enough food, shelter and various basic comforts at the least. I suppose we should be on the same side, but I’m just so angry at them because more than anyone they get in the way of any practical solutions. The most annoying thing about them is how they don’t examine all the evidence. They just dismiss or ignore anything that doesn’t fit their preconceived notions. I’ve spent a lot of time reading and thinking about both sides of the argument, but they only listen to each-other. I guess in that way they are a lot like a religion.
Tony Carden — The steam used to power the electric generator requires condensing. Ordinarily this reject heat evaporates water.
Any source about Rankine cycle engines will explain further.
I love the way you fall back to “renewables require too much land”. How much land has the almost 5GW of solar installed in Australia consumed? Essentially none. It’s all on rooftops.
Friends – let’s not post any replies to a comment that is clearly off topic. The previous thread was choked up by our own responses to a troll‘s graffiti. Instead we could send the URL to the moderator and request that it be deleted as being off topic.
I opine that “religion” is the wrong concept for those taking faith in 100% so-called renewables. My, but religion is a fuzzy concept:
http://plato.stanford.edu/entries/religion-science/
makes a stab at it. “Faith” might be better and here is an article from the religious perspective:
http://plato.stanford.edu/entries/faith/
What I see instead of either is a deep intranisgence on the part of some in failing to address properly so-called renewables issues in powering a reliable electric grid. I don’t know the proper psychological term, although the Afrikaans “verkrampte” seems apt.
For example, I have often suggested a model grid based on Bonneville Power Administration data for the BPA balancing authority region. I request advocates of this or that to indicate how they would reliability power the grid and at what wholesale cost. I have yet to see a single response.
Here is the simplified grid, with every day exactly the same: from 6 am to 11 pm the grid is at 100% while overnight it is at 70% of maximum load. Choose your own maximum in the range 10-30 GW, a modest size.
I have down this several times in the past, leaving the results on various threads of Brave New Climate or also maybe
http://bravenewclimate.proboards.com/
Using realistic LCOE figures I always concluded that powering mostly by nuclear equipped with therrmal stores is less expensive than adding any wind power at all, but that some household and commercial solar PV, up to about 30% of the maximum load at noon, could be accommodated for little additional cost for utility ratepayers.
I didn’t do this for the current costs for wind generators, but given the way the analysis has to go there isn’t much point in doing it again. The basic problem of providing backup for when the wind resource is not available remains. I refused to consider using natgas as that is nowhere near carbon neutral. So basically one has to power down some of the nuclear generators when the wind is blowing and this is never, ever, cost effective. The same holds for solar PV, but the utility recovers costs associated with cloudy days by charging those customers with their own solar PV at a higher rate for the power that is consumed above their sunny day allotment. Up to a point this works.
This challenge remains open to advocates of any mixture of generators; be sure to include ample reserves against unplanned generator tripoffs. Recall that pumped hydro is highly geography specific and so is not generally applicable.
Mark4asp – “RE offers something apparently new, it’s the environmentalist’s heaven to their climate change hell. Heaven and hell are just metaphors here.”
I fully agree with this, but to me this smacks of religiosity.
If we don’t take seriously the urgency of taking action on climate change then the rationale for nuclear energy uptake can be left to market forces, there would be little need to press buttons.
Tony Carden – the densities discussed by MacKay are power densities not energy densities. And yes Jens, capacity factor does matter when converting power densities to energy densities. But the capacity factor for nuclear is about 3 times wind and 6 times solar PV which makes the land use for nuclear a v. small fraction of the land use for RE as MacKay clear shows in his TEDx talk.
EVcricket, My estimate to power all Australia with solar PV would require 1700 sq km of roof and land area. The total roof area is about 400 sq km so we would still need 1300 sq km of land. We could do the same job with about 30GW of nuclear or 30 sq km.
Chris H said – “If we don’t take seriously the urgency of taking action on climate change then …”
Yes, that sense of impending doom is certainly what is driving my own passion, and I hope, many of the people I talk with. As a means of laying blame, I guess that is politics and eventually the re-writing of history by the survivors. As a call to action, it is about our survival. Said like that, it is no more religious than a revolutionary calling out “the British are coming!”.
What we mean by “our survival” is certainly an ethical question of whether to include the welfare of future generations amongst the interests of today’s generation. To that extent I guess its religious. But if the complacent young twits would get off their backsides and march in the streets, it would be political.
But that vision of impending doom is not shared by a renewable energy enthusiasts. To them the issue is not whether wind or solar is carbon free, but whether it is renewable. To them, the disaster ahead is that we are about to run out of non-renewable resources. This must have been contradicted by every geologist they have talked to across the last 50 years, so their contrary belief does smack of blind faith, of religion.
Martin,
Is this better
The Math is quite simple.
A. 1 gw = 1000,000,000 w (one billion)
B. 1sqklm =1,000,000 Sqm
A/B = 1000w/sqm
Further in relation to your comment about Solar PV how do we deal with the intermittentency of Solar PV ( where do we get say 10 to 15 GW of power from at night).
David Benson,
Both coal and nuclear power plants use superheated(say 250 degrees C) steam to drive the turbine that drives the generator. With Nuclear one of its inherent flaws is that to achieve this temperature water must be contained at pressures in the order of 80 atmospheres. This is one of the inherent and limiting flaws in all Pressurized Water Reactors, hence the Chernobyl and Fukishima incidents.
The designs of both the Integral Fast Reactor(IFR) and the Molten Salt Reactor (MSR) do not use water for cooling or heat transfer. They both operate at temperatures in excess of 700 C.
It is proposed that they use Closed Cycle Gas Turbines (CCGT) to drive the generator.
My point is simply that because these reactors do not need water is another very good reason for investing R&D funds into their development.
Tony Carden — The existing IFR outside of Russia is the GE-Hitachi S-PRISM which does indeed use a steam generator. I don’t know about the Russian BN series much, but the BN-600 has had at least one sodium fire which suggests that it also has a steam generator.
Supercritical carbon dioxide Brayton cycle generators are not yet in production. Soon, we hope.
Pertinent to this article, though the comment section has mostly been spared so far: http://bravenewclimate.com/2015/02/25/the-argument-for-nuclear-energy-in-australia/#comment-390488
Tony Carden — Jens question about water evaporation led to some confusion. The water used to remove heat from the reactor core is not the water being evaporated to remove the excess heat at the bottom end of the generator’s Rankin cycle. A coal burner has the same necessity of removing the reject heat. So does a concentrated solar generator.
None of wind, solar PV or hydro have this problem, just lots of others.
David,
I am not sure in relation to IFR’s but for MSR’s no water is used to transfer energy from the reactor core to the turbine. It is done via an inert gas such as Helium.
Steam driven turbines operate at their most efficient when the steam is heated to 250C approx. For water conservation purposes it is then released into the cooling towers for recycling and resultant heat reduction.
I am not aware of the figures for water consumption of steam driven power plants but it is considerable. I would welcome a figure.
I am not that familiar with the Rankine Cycle so I am not sure of how much energy needs to be removed from the system. But would it be possible to use a closed water system similar to a car radiator at the bottom end of the Rankine cycle. Hence minimal water consumption.
As regards the 1 Gigawatt reactor requires 1 square kilometre formula, Bruce generating station in Ontario has eight reactors totalling over 6 Gigawatts on 0.9 km2. There is also room for a decommissioned reactor and storage for most of the province’s low and intermediate waste; two more reactors had been planned for the same site. That would have been nearer 10 GW per km2.
Hi Martin
If you assume average capacity factor for wind and average capacity factor for nuclear you are probably just about right assuming the Nuclear deliver three times more energy relative to nameplate capacity.
The general concept of the article is however future oriented and questioning if there is any reason to consider renewables.
If you consider new Nuclear vs new wind capacity Nuclear delivers no more than two times more energy relative to nameplate capacity.
The land use issue presented by MacKay is totally manipulated to the point where just presenting the nonsense devaluate credibility.
If you wanted to manipulate figures the other way around you could argue that wind turbine land use is limited to the area of the ground that they occupy.
You are a mathematician so you know how to do analysis and how to calculate so I believe you could do better if you wanted to try.
It could actually be interesting to see a fair calculation of the land required for the different technologies to power the world.
As for the notion that RE is a religion I can certainly answer no for my own part. My concern is similar to most that takes an interest in Brave New Climate, I think there is enough evidence that shows we have to limit CO2 in the atmosphere.
As for the means to be used I would argue that we should use the cheapest.
Jens – Nuclear is cheapest because of, among other reasons, the renewables overbuild requirement, the expense of the largely non-existent storage infrastructure (and material requirements to create it), the transmission requirements, and the general waste of limited resources associated with intermittent renewables. This is not to say that the technologies will not improve. I hope they will. However, betting the future on such hopes seems very foolish.
Respectfully, you seem to exhibit what is sometimes referred to as “nuclear exceptionalism.” (NNadir’s term, I believe). E.g., you indicate mining area must be taken into account in calculating nuclear’s land use impacts, but ignore the corresponding materials mining requirements for renewables, e.g., the neodymium mining referenced in one of Professor Nicholson’s links (and other rare and less rare materials that must be secured, fabricated into structures and devices, etc., and transported and put into place, and [unless the related problematic materials are to become “distributed toxic waste”] decommissioned and controlled at the back end).
If you were to read through the history of matters addressed by Barry Brooks’ and guest bloggers on bravenewclimate.com you would find that the kinds of issues you raise have been thoroughly and thoughtfully addressed, most likely more than once.
I would suggest you “do the numbers” for an energy system built largely around inevitably intermittent renewable energy. Civilizations require whole energy systems. Barry has done the numbers, Mackay has done them, Armond Cohen (Clean Air Task Force – another former anti-nuclear activist who previously thought “we can do it all with renewables”) has done them, and others have done them as well. Rigorously. A common consequence of doing the numbers rigorously is loss of faith in renewables, standing alone, as a cornerstone of a viable climate and energy solution.
If you have some compelling analysis after “doing those numbers,” then provide a link and I expect a number of people who follow discussions here would look at it. It is always useful to challenge one’s beliefs and make room for other possibilities.
However, isolated data points combined with sweeping unsupported statements do not constitute a position that merits serious consideration. Instead, this kind of disjointed approach only seems to re-validate Mr. Nicholson’s theory about renewable energy advocates holding something equivalent to a belief system based mostly on faith instead of facts.
“If you were to read through the history of matters addressed by Barry Brooks’ and guest bloggers on bravenewclimate.com you would find that the kinds of issues you raise have been thoroughly and thoughtfully addressed, most likely more than once.”
At this point this should almost be pinned to the top of the blog. I guarantee any and all criticisms and objections to nuclear power have indeed been addressed in the hundreds of articles here.
On Armond Cohen, his analysis is thorough and incisive and essential viewing:
Tony Carden — Turbines are heat engines and so subject to the limitations of the
https://en.wikipedia.org/wiki/Carnot_cycle
The efficiency of which which cannot be actually obtained in practice. Gas turbines use the practical
https://en.wikipedia.org/wiki/Brayton_cycle
for which the helium or supercritical carbon dioxide closed cycle turbine is an astounding 45% efficient; 55% of the supplied heat is rejected to the environment:
http://phys.org/news/2011-03-supercritical-carbon-dioxide-brayton-turbines.html
Steam turbines use the older
https://en.wikipedia.org/wiki/Rankine_cycle
and due to the temperature limitations imposed by the zirconium alloys used to hold the uranium pellets in position is only about 38% thermally efficient; 62% of the generated heat must be rejected to the environment.
For steam, rejection is done through a condenser. The turbine water is condensed back to water which is pumped back to the steam generator. On the other side of the condenser the choices are water evaporation, once-through cooling water, or air cooling. I know of no nuclear reactor which uses or ever used air cooling. I know of a few coal fired power plants which use air cooling. The difficulty with air cooling is that about 5-8% of the generated electricity is consumed running the fans.
Finally, there currently are no MSRs generating electricity for any grid. Until some of the projects in
http://www.world-nuclear.org/info/Current-and-Future-Generation/Molten-Salt-Reactors/
are actually built we won’t know how economic the design is in practice.
Any developing technology requires the faith of its proponents, INCLUDING advanced nuclear.
Agreed Eli. So we need to pursue a joint strategy of deployment of technologies that we KNOW work at scale (e.g. thermal nuclear in France, Ontario, Sweden etc.) and pursuit of technologies that we hope (have faith) will work even more effectively in the future (advanced nuclear, advanced solar, large-scale energy storage). Where the 100% technosolar (i.e. not hydro/biomass) advocates fail is in not recognising the criticality of both coupling faith with proof.
Sorry, wrong. Steam turbines continue to increase efficiency with increasing input temperature up to the limits of materials currently available. So does every other heat engine. Supercritical steam plants use steam hotter than the critical point of water (374°C, 22 MPa), and the trend is toward ultrasupercritical steam plants. Next Big Future recently ran a piece on supercritical nuclear reactors which would function like BWRs but operate well above the critical pressure. There would be no phase change in the coolant so no issues of thermal shock or localized heating from boiling.
Sodium-cooled reactors operate in the neighborhood of 500-550°C to maintain overhead below the BP of the coolant. MSRs built so far run considerably hotter, up to 850°C if I recall my reading about the “fireball reactor” correctly. If either was paired with a steam turbine, it would be at least a supercritical steam system. No mechanical engineer worth his salt would take a 550°C coolant and design a steam generator to turn out 250°C steam for a system primarily designed to generate electricity. You can convert a lot more of each BTU of heat into work if you start with 550°, 30 MPa steam. It’s a simple matter of less entropy being generated, so less needs to be rejected as waste heat.
If you don’t know how to use the steam tables in the back of a thermodynamics textbook, you aren’t informed well enough to have a worthwhile opinion of your own on this issue. If you need an expert, hire one. For $100 per hour I will calculate all of the theoretical efficiencies you like, with as many practical variations (like different turbine efficiencies) as you want thrown in. You’ll get OpenOffice spreadsheets including all data, with sources cited. Since they would be works for hire, you could post them or do whatever you like with them.
Change in entropy is defined as ΔS = ΔQ/T(abs). You can see that putting in a megajoule of heat at 550°C (823 K) yields less entropy than doing it at 250°C (523 K). Every bit of entropy you input or create has to be rejected to the environment, and that means ΔQ (waste heat), so less entropy is always better.
The Windscale reactors were air-cooled, but they were not used to generate power.
@EP
Further to the operating temperatures of sodium-cooled reactors, it looks like formation of fuel-cladding eutectic becomes a concern before melting, though melting greatly accelerates this damage.
http://www.sciencedirect.com/science/article/pii/S1738573315000753
As for air cooling, at least after SCRAM PRISM is designed to rapidly draw air in and across the outer skin of the RPV, accelerating passive cooling.
EBR-II, the prototype for the Integral Fast Reactor and PRISM, was also air-cooled. The test site is located in the Idaho desert, near Arco.
EBR-II drove a steam cycle prodicing 19 MW(e), which both lit and heated the Argonne (now Idaho) National Lab site. Emergency cooling was air, but not primary cooling.
Kogan Creek coal PS of 750 MW, is air cooled. So that more than 2 GW(th) of air cooling – for steam condensing. Technology that works for coal is ready for nukes as well. So it’s not true, nukes don’t have to consume water.
Frank Jablonski
First of all I do not find the prospect of being able to replace fossils with renewables unrealistic or foolish.
The dependence on rare earth materials is not very expressed for wind turbines and a company like Enercon does not use any rare earth materials in any of their up to 7MW large turbines. http://www.enercon.de/en-en/1337.htm
Most others use rare earth for economic reasons purely including Siemens that use approximately 200 kilo in their 6MW turbine.
The environmentally problematic conditions connected to rare earth mining in China should be addressed asap.
If you assume 50% capacity factor in a the projected 25 year lifetime a 6MW Siemens wind turbine will produce 675000MW so for each produced MW there will be spent 0,3 gram. If you assume that 99,5% will be recycled the actual usage of rare earth materials per produced MW is approximately 0,0015 gram.
Back to the real topic I would like to get my curiosity satisfied about the rational substance of the debated differences in power density it could be interesting to get real values on the table.
However at the end of the day the energy discussion should be about how to reduce pollution of any kind while producing energy at the cheapest feasible price point.
I found a map over wind resources and this indicates that you have fine resources in Australia. http://www.renewableenergyst.org/wind.htm
And a more detailed one http://www.renewablessa.sa.gov.au/files/121219-windresourcemappingaustralia.pdf
And not much habitation in the windy desert and grassland areas http://www.ndca.asn.au/other-information/about-australia/
The argument for nuclear should at the end of the day be that you can deliver electricity cheaper.
$0,031 US cent per kWh on 20 year PPA without subsidies was the average standard in 2013 for US interior and this appears to be a target price that could be achieved in parts of Australia as well.
To all interested in running nuclear with no water consumption I think the interest regarding the existing fleet of nuclear power plants is rather academic because the majority of nuclear plants runs with water cooling for a reason and that reason is that you can extract more energy with water usage. In arid and semi arid areas without access to seawater cooling the problem is real for thermal power plants – and significant for everyone that is locally affected of water shortage or changed aquatic environment.
The flashed water vapor contains several gasses whereof some are greenhouse gasses such as CO2, N2O, CH, O3 and H2O.
While water will return as rain all the other mentioned greenhouse gasses has significantly longer lifetime in the atmosphere.
If any of you have knowledge about the issue I would like to be informed.
For attempts to use air cooling it is important to notice that you then will make the output from Nuclear more variable with less output when the ambient temperature is high and more when it is cold.
Jens – several authoratative voices have told you that nukes dont HAVE to have water, yet you keep repeating it as gospel that they do. So “In arid and semi arid areas without access to seawater cooling the problem is real” is not true. Kogan Creek is in a drought-prone area of Queensland and it has no such problem. You bear false witness.
Jens Stubbe,
There is plenty of literature on the FULL life cycle GHG emissions of nuclear power. You could start with NREL Harmonized assessments:
http://www.nrel.gov/analysis/sustain_lcah.html
Sorry to say, but your comment immediately above is just unquantified FUD.
Roger Clifton
Here is one authoritative source that I suppose you do not find to be a member of my choir. http://www.world-nuclear.org/info/Current-and-Future-Generation/Cooling-Power-Plants/
They are not in denial about cooling.
“The amount of cooling required by any steam-cycle power plant (of a given size) is determined by its thermal efficiency. It has essentially nothing to do with whether it is fuelled by coal, gas or uranium.
However, currently operating nuclear plants often do have slightly lower thermal efficiency than coal counterparts of similar age, and coal plants discharge some waste heat with combustion gases, whereas nuclear plants rely on water.
Nuclear power plants have greater flexibility in location than coal-fired plants due to fuel logistics, giving them more potential for their siting to be determined by cooling considerations.
The most common types of nuclear power plants use water for cooling in two ways:
To convey heat from the reactor core to the steam turbines.
To remove and dump surplus heat from this steam circuit. (In any steam/ Rankine cycle plant such as present-day coal and nuclear plants there is a loss of about two-thirds of the energy due to the intrinsic limitations of turning heat into mechanical energy.)
The bigger the temperature difference between the internal heat source and the external environment where the surplus heat is dumped, the more efficient is the process in achieving mechanical work – in this case, turning a generator[1]. Hence the desirability of having a high temperature internally and a low temperature in the external environment. This consideration gives rise to desirably siting power plants alongside very cold water.*
* Many power plants, fossil and nuclear, have higher net output in winter than summer due to differences in cooling water temperature.”
World Nuclear brings an EPRI graph over the cooling water usage, which indicate nearly 850 Gallons per MW or approximately 3,2 liters per kWh. And another graph from NETL suggesting 2,36 liters per kWh.
World Nuclear clearly states that running Nuclear air cooled is feasible but comes at an extra cost and reduce output.
Despite the interesting question related to the released greenhouse gasses from the cooling water there is no quantification.
The link to NREL analysis from Quekka does not even mention the problem.
Ps. I have at no point argued that Nuclear power plants has to use water, I have just quite correct mentioned that they all do and it is interesting to analyze the emissions and the effects on the aquatic environment and farming etc.
In some years we will see how solar and storage are going to scale.
Till then why not look into other things?
Here is something with huge potential. Imagine reducing material input over conventional wind by 20 and a CF between 70-90.
A proposed 5GW plant with a CF around 90 would cost around 1.5b€.
Anyways, let’s help them give it a shot.
https://www.indiegogo.com/projects/kitegen-the-ultimate-green-energy-solution
Thanks E-P. I dug up my copy of Len Koch’s EBR-II book, in which he says the following on pg 3-35 to 3-36:
EBR-II used a dry cooling tower, with water used to cool & condense the condenser LP turbine discharge steam.
Rod Adams noted the following:
I stand corrected.
I disagree with Eli Rabett’s conclusion. Proposed engineered artifacts are considered with rational confidence that such will work as specified and without too much of a cost overrun.
http://www.oxforddictionaries.com/definition/english/faith
is not required for action, only sufficient trust in the design and economics. Sufficient trust is rational and never complete confidence.
An insanity of so-called renewables:
http://thinkprogress.org/climate/2015/04/16/3644889/woody-biomass-is-thicket-of-trouble/