The following post is intended as a working paper for discussion. (It builds on work started by Peter Lang back in 2009, Does wind power reduce carbon emissions?) This current work is based on the methods and conclusions from the recently published work by Herbert Inhaber in the peer-reviewed journal Renewable and Sustainable Energy Reviews, entitled: “Why wind power does not deliver the expected emissions reductions“, and is applied to the Australian situation as a case study.
Clearly, there are large uncertainties on the Inhaber equation and they are not quantified. Discussion will almost certainly take place in the scientific literature about the Inhaber equation over the next few months to years. Inhaber, does point out that the chart is schematic, we do not have the emissions data needed and the many major uncertainties.
Peter and I look forward to your feedback. This is an important technical matter to resolve, with potentially strong implications for energy policy.
I note that there may be circumstances where some or most of these problems can be overcome, where the grid is ‘evolved’ or set up in a specially configured manner (unknown cost) — the below findings are most applicable to existing grids which are having wind added incrementally (i.e. all current [real-world] jurisdictions).
A 7-page printable PDF version of this paper can be downloaded here.
Addendum: Peter Lang’s Response to the American Wind Energy Association’s reply
————————————–
CO2 avoidance cost with wind energy in Australia and carbon price implications
Guest Post by Peter Lang. Peter is a retired geologist and engineer with 40 years experience on a wide range of energy projects throughout the world, including managing energy R&D and providing policy advice for government and opposition. His experience includes: coal, oil, gas, hydro, geothermal, nuclear power plants, nuclear waste disposal, and a wide range of energy end use management projects.
Introduction
This paper presents a simple analysis to estimate the amount of CO2 emissions avoided by wind generation and the cost per tonne avoided as wind penetration increases from 0% to 20%. The carbon price implications are discussed. The analysis is based on a paper by Herbert Inhaber (2011)1. The analysis is for Australia’s National Electricity Market.
Emissions Avoided by wind generation
Herbert Inhaber (2011) reviewed eleven studies of CO2 savings by wind generation and concludes wind generation becomes less effective at reducing CO2 emissions as wind penetration increases. That is, wind generation avoids less CO2 as wind energy’s share of total generation increases. Inhaber explains:
as wind penetration increases, the CO2 reduction will gradually decrease due to cycling of the fossil fuel plants that make up the balance of the grid.
Below is an extract from the “Conclusions” and “Uncertainties” sections of Inhaber’s paper [in this extract, references to ‘Fig. 3’ are to the figure in Inhaber’s paper, which is reformatted and called ‘Figure 1’ here):
There are considerable uncertainties about how fast this decrease occurs, and the curve in Fig. 3 should be taken as only suggestive. However, the arc seems to be a mirror image of a sigmoid curve, with an equation:
where Q is the CO2 reduction in percent, x is the wind or intermittent renewable penetration of the grid in percent, and c is a constant, of the order of 0.2 in Fig. 3.
Figure 1: [Inhaber’s Fig. 3 reformatted to make it easier to interpret. In Inhaber’s paper, Fig. 3 is presented with log-scale on the vertical axis.]
5. Uncertainties There are considerable uncertainties in developing a curve of this type. A few of the many, not necessarily in order of importance, are:(a) The mix of fossil fuels used in the grid and the type of gas turbines in particular;
(b) Some of the literature on wind is of a polemic nature, either advocating its widespread use or pointing out its deficiencies. Care has to be taken to concentrate on the facts and leave opinions aside;
(c) Whether renewable energy is exported to other countries, as in the case of Denmark. This could skew results;
(d) The number of cycles of the fossil fuel sources that take place over time;
(e) What fraction of fossil fuel plants in the grid are relatively inefficient open-cycle gas turbines (as opposed to more efficient closed cycle gas turbines);
(f) The carbon dioxide intensity emitted from the fossil fuels used in the grid;
(g) The degree of variability of wind resources over a period of time, and a host of others.
(h) Funding sources for some literature is sometimes from proponents or opponents of the energy source;
(i) Some of the literature is not peer reviewed, posing potential problems in quality control.
For simplicity, let’s assume the average CO2 emissions intensity of Australia’s electricity generation is 1 tonne per MWh (The figure varies by state and by year ).2
From Inhaber’s chart, at 1% wind energy penetration, emissions are reduced by 90% per MWh of wind generation. This equates to a reduction of 0.9 tonne per MWh of wind energy. However, at 20% wind energy penetration the CO2 reduction is just 3.6%, or 0.036 tonne per MWh of wind energy.
CO2 Avoidance Cost
For wind power to be viable the price for electricity would need to be about $120/MWh. The current average wholesale price of electricity is about $30/MWh3. So wind energy must be subsidised by about $90/MWh. If we have a carbon price of $25/MWh then the Renewable Energy Certificates (RECs) need to reach $65/MWh to make wind viable. (That means the consumer must subsidise wind by $90/MWh, or three times the current wholesale price of electricity.). The figures are summarised in Table 1.
Let’s calculate the cost of emissions avoided by wind generation at 1% and 20% wind energy penetration.
From Inhaber’s chart, at 1% wind energy penetration, CO2 reduction is 90%. Using the emissions intensity for electricity of 1 t/MWh this equates to 0.9 tonnes per MWh. Wind energy costs $90/MWh more than the current average cost of electricity. This is the cost we must pay to avoid CO2 emissions with wind energy.
At 1% wind energy penetration, the cost per tonne CO2 avoided is:
$90/MWh / 0.9 t/MWh = $100/t CO2 avoided.
At 20% wind energy penetration the cost per tonne CO2 avoided is:
$90/MWh / 0.036 t/MWh = $2,500/t CO2 avoided.
These figures are for the cost to avoid an additional tonne of CO2 by increasing wind penetration.
Figure 2 shows the CO2 avoided and the cost of avoidance versus wind energy penetration.
Sensitivity Analysis
The CO2 avoidance cost is sensitive to the wholesale electricity price and to the minimum price needed for wind power to be a viable investment. Figure 3 shows the results for six scenarios. The inputs for the six scenarios are listed in Table 2:
The greatest uncertainty is the Inhaber equation. As Inhaber states “There are considerable uncertainties in developing a curve of this type.” However, to conduct meaningful sensitivity analyses on the range of possible values for the Inhaber equation is beyond the scope of this simple analysis. Inhaber’s paper does not include ranges for the constants in the equation.
Carbon Price Implications
A carbon price of $2,435 per tonne CO2 would be required for wind power to be viable at 20% penetration. This is for Scenario 1. The carbon price required for the six scenarios is plotted in Figure 4.
A carbon price of $2,435 per tonne is one hundred times the expected initial carbon price of about $25 per tonne CO2. This indicates how much the carbon price would need to increase to make wind power reach 20% penetration based on carbon price with an REC price about double what it is now. The Australian Renewable Energy Target is 20% renewables by 2020 and most of this is expected to be provided by wind power. The carbon price would have to increase by a factor of nearly one hundred above the likely initial carbon price to achieve the target.
For the carbon price to stay below $100/tonne CO2, wind energy penetration would have to be less than about 5% and the Renewable Energy Certificates price above $65 (for Scenario 1).
Another issue is that the carbon price will be paid by the back-up generator owners not the wind farm owners. This is clearly unreasonable since wind is contributing to reduced efficiency of the back-up plant.
Conclusions
As wind energy penetration increases from 1% to 20% the CO2 avoidance cost increases from $100 to $2,500 per tonne.
The quantities and costs calculated are sensitive to the input assumptions and input data but the broad conclusions are robust to the range of input values tested.
Considerable uncertainties apply to the inputs for the Inhaber equation upon which this analysis is based and therefore to the results. However, these uncertainties have not been quantified.
A carbon price of around $2,500 per tonne would be needed for wind power to reach 20% penetration. The Renewable Energy Target is 20% renewables by 2020 and most of this is expected to be provided by wind power. Therefore, the expected initial carbon price of about $25 per tonne would have to increase by a factor of one hundred to achieve the Renewable Energy Target.
For the carbon price to be below $100 per tonne wind energy penetration would have to be less than about 5% (and Renewable Energy Certificates price above $65 per tonne).
Wind energy is a high cost way to avoid CO2 emissions.
Australia is paying a high price for policies that mandate renewable energy while at the same time prohibiting other low emissions electricity generation options.
References
1. Herbert Inhaber (2011). Why wind power does not deliver the expected emissions reductions. Renewable and Sustainable Energy Reviews 15, 2557–2562
2. Department of Climate Change and Energy Efficiency (2010). National Greenhouse Account (NGA) Factors, Table 5.
3. Matt Chambers, “Force of the near future”, article in “The Renewable Energy Special Report”, The Australian, 16 May 2011; figures attributed to Tim Nielsen, head of economic policy at AGL.
4. ABARES (2011). Energy in Australia 2011. p22
5. EPRI (2010). Australian electricity generation technology costs, – Reference Case 2010. Table 10-9 to Table 10-11, p10-4
368 replies on “CO2 avoidance cost with wind energy in Australia and carbon price implications”
Neil@ “…the wind graph did not include WA( or QLD either) and was not “the entire .wind Australian wind fleet” ”
OK, lets unpack that. First it should be clear I’m referring to the None-Scheduled wind farms reported to the AEMO on the NEM, as that is what is shown on the charts. The data is obtained here:
http://www.aemo.com.au/data/csv.html#nsgendata
If it wasn’t clear then I apologise to you & BNC readers. But your comments regarding not including WA and QLD are irrelevant. QLD currently has a mere 2 tiny wind farms:
http://ramblingsdc.net/Australia/WindQld.html
Windy Hill 12MW
Thursday Island 0.45MW
so they do not appear in the AEMO data because they are so piddlingly tiny.
WA, which is not connected across to Eastern Aus in any case, also has barely any installed capacity:
http://ramblingsdc.net/Australia/WindWA.html
In fact there are only 2 worth mentioning:
Alinta 89.1MW (with a claimed 44% CF), located far up the coast in mid north western WA (370km north of Perth) :
http://infigenenergy.com/assets/australia/alinta-wind-farm-wa-australia.aspx
Emu Downs 79.2MW (200km north of Perth)
http://www.griffinenergy.com.au/default.aspx?MenuID=78
There is of course Albany:
Albany 21.6MW
http://www.verveenergy.com.au/mainContent/sustainableEnergy/OurPortfolio/Albany_Wind_Farm.html
My favourite quote from the Albany we page is :
“Albany is connected to the main electricity grid. – the South West Interconnected System (SWIS). When the wind isn’t blowing the city is provided with power via transmission lines from Verve Energy’s large coal and gas fired power stations further north. On some occasions the wind farm exports a small amount of power north along the transmission network.”
So Albany pretty much just serves Albany and of course is tiny. The rest in WA are all ultra tiny 0.6 to 3.6MW.
Regarding the OZ-Energy Analysis link, it is interesting that comment 10 states regarding smoothing:
“If anyone is interested, some time ago I constructed a simulation model which uses actual output data at 5 minute intervals from all of the 22 current windfarms that have data publicly available and replicates them cookie cutter style across the whole of Australia by the simple mechanism of time shifting the data to represent weather systems passing from west to east. The model now has 21 months actual data and shows substantial smoothing but still indicates periods of extremely low output. I will be interesated to compare my models outputs with the outputs of this highly theoretical model.
I have also supplemented the model with confidential data from two solar farms in NSW and found very little improvement in these low output periods underlining the need for substantial backup generation or else storage.
In addition I have applied the same technique to Ireland’s windfarms and Canadas windfarms and obtained strikingly similar results.”
I suppose it hinges on many things including already discussed above and a) can we afford the WA interconnector and b) can we afford the wind farms and c) will the optimistic models deliver a secure supply in reality. There’s probably a whole bunch of d’s e’s and f’s too … perhaps this is veering off topic ??
Back to the point, my opinion, based on the discussion article, Inhaber’s paper (and others e.g. Katzenstein & Apt) and comments above, is the CO2 avoidance cost is huge! Get rid of the stupid RET.
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/////In the latter case we need fossil fuel back up capacity to back up for the wind power (together with all its emissions and fixed costs), or you have the cost of the transmission line – which is more than the cost of nuclear://///
Not entirely true Peter — it is *technically possible* to store enough energy in Hydro Dams.
http://eclipsenow.wordpress.com/storing-energy/
Note that I did not say *economically competitive* — and I raise that issue on my page above. However, if Australia is dumb enough to waste some serious money on a Renewable venture, I wonder if it *is* now technically possible to go 100% renewables… and what it would *really* cost? (Unlike the reports from the rather ideological Beyond Zero Emissions report, I’m guessing it’s MUCH more expensive).
But that’s not the point here is it? If one 20 meter high, 7k diameter saltwater hydro dam on the Nullarbor costing a few $billion could store enough energy to run ALL OF AUSTRALIA for 10 hours, don’t you think that a 100% wind grid at least becomes *technically* possible?
Hey, if you’re REALLY worried about baseload why not just build 2 or 3 of these National 10 hour ‘batteries’? We have a nation of 21 million people to spread the costs around, and a likely carbon tax to boot.
It *could* be done. The question is would the average Australian really want to if PROPERLY informed about today’s Gen3 and Gen4 nukes?
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@ Peter Lang
(inflammatory comment by PL has been deleted)
I was hoping for (deleted personal opinion on other person) Peter Lang to address the seawater Hydro dam that could apply anywhere on earth that has a large enough open real estate atop an ocean cliff. . I need help with *costing* this hydro thing sometime.
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Thank you all for an intelligent discussion of this important issue.
I have just read all 160 coments, although I admit I have not yet waded through all of the referenced papers yet (there is at least a week’s reading there, probably more). Peter, I’m afraid I do not find that ‘this has been argued to closure’, and feel that your attempt to close down the dicussion as if it was agreed and move on is not yet appropriate.
I have not yet been convinced by either ‘side’, although both have made some good points and produced some good evidence. It does seem that it ought to be the case by now there there was sufficient evidence around the world to reach resonably robust conclusions, and agree both current actual emissions reductions from wind, and future probable emissions reductions.
There are many comments I could make after reading that lot, but until I’ve absorbed more of the references I’ll largely hold fire and just say this:
I quite agree that nuclear needs to be part of a low-carbon mix (or at least that it is extremely difficult and expensive to do without it).
However, most of this debate seems to be saying ‘wind is no use in reducing carbon emissions due to the costs of load-following, so we should use nuclear instead.’
But nuclear is completely useless for load-following in a different way – it has very low slew-rates so is only used for base-load. You’d still be using gas for all the hour-to-hour variation, so I don’t see that a low-carbon approach is being advocated by the pro-nuclear people any more than by the pro-wind people. In both cases you still have a big chunk of FF (mostly gas) generation for hour-hour variation following. (Does the moderator really want me to give a reference for the low slew-rate of nuclear, or can we take that as ‘well known’?)
A genuinely low-carbon solution surely needs all/most of nuclear, CSP, solar PV, wind and hydro, plus some gas. It’s not an either/or thing, and that seems to be how some people are arguing here.
An why so little mention of CSP? – Australia has exceptional solar resource and plenty of space per person to put it in, so this seems like it ought to be part of the mix. I’d expect it to have similar slew-rates to CCGT, but am no expert.
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This is the new efficient quick response combined cycle plant from GE
which can change output by 50 MW a minute and takes 30 minutes to start, I presume that includes steam. No info on average CO2. If anything it tends to confirm fossil fuel lock-in by renewables.
I note in relation to the proposed Morwell Vic plant that gas will cost $7 per GJ as opposed to 60c for brown coal. Liquid transport fuels cost $45 per GJ and will soon compete with gas. No amount of hydrocarbon fuel conversion efficiency can ultimately beat high fuel prices.
Eclipse Now I don’t dismiss seawater pumped hydro as Seligman seems to have done his sums fairly carefully. Trial plants in Japan, Hawaii and Ireland will confirm or deny the economics and reliability.
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Hi John,
what do you mean by ‘trial plants’? Don’t we know from fairly old data how much power we’d get from a given amount of stored water?
I guess the only questions here in a sea-water BATTERY (not power source) might be how much water (and therefore energy) we lose to evaporation.
But otherwise, isn’t it fairly easy (for engineers — not myself) to calculate how much it will cost to build that 7km diameter, 20meter high earthen wall, line it, and whack hydro turbines onto it? These are pretty old technologies. We’re happy to have low guesstimates of GenIV power which I understand still requires significant materials development issues to be solved, but when it comes to a plain old hydro dam we say things like “It’s never been done before” because this one is a salt ‘battery’ only?
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EN there must be issues like fluid friction, turbulence within pipes, optimum operating range for a particular turbine design, valve response lag, cavitation in pumping uphill, FOAK costs, maintenance issues such as leaks and cleaning of filters. It may be the recoverable energy is more than double for a 200m drop than a 100m drop i.e. it’s non-linear. A weird costing issue I’ve noticed is that bored hydro crews sit around watching dials then if something goes wrong there aren’t enough people. All this needs to be tested.
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@Wookey, Modern Gen II nuclear plants can load-follow, many with slew-rates on a par or superior to other stem thermal plants. These are more than sufficient for everything except peaking.
The issue is that wind and solar, being unpredictable cannot serve that function ether reliably without some form of storage.
However what ever form of storage that is used, or might be developed, could be recharged less expensively, by surplus power from a nuclear power station.
Therefore, wind and solar are not, and never will be needed in ether case.
We have gone over this topic before here ad infinitum, perhaps it is time to have a FAQ to point to for questions like this.
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Wookey, @ 31 May 2011 at 5:35 AM
1. Regarding my urging to move the discussion forward to the policy implications, I’d point out that much of the argument about how much emissions is avoided by wind generation, has been discussed at length on other threads on BNC. The argument is not going to progress any further because it bogs down in wind advocates repeating their positions and making comments about bits and pieces of irrelevant comments – generating FUD and confusion. This thread has reached this repetitive stage. Furthermore, as Inhaber points out, we simply do not have empirical emissions data at the times scale required. Australia has no emissions measurements at all. The sensitivity analysis looking at the full range of possible % CO2 emissions avoided per MWh. This shows that no matter what values we use, wind power is a very high cost way to avoid emissions. This is what is important. From that we can move forward to the policy implications. Unfortunately, it seems some do not want to move onto discussing the policy implications.
2. There is a great deal of background on other threads on BNC. Those not familiar, and interested, may want to look at the previous posts on the “Renewable Limits” tab.
3. Nuclear can load follow if designed to do so. The French NPPs have always done so. Look at this graphic. Move the cursor across the area chart and watch the changes on the pie chart below. http://www.rte-france.com/fr/developpement-durable/maitriser-sa-consommation-electrique/eco2mix-consommation-production-et-contenu-co2-de-l-electricite-francaise . Spend some time on these charts to get a feel for what a neaqr ideal arrangement would look like.
4. Areva claims the EPR is designed to ramp at the rate of 5% of maximum power per minute throughout the range of 60% to 100% power and can operate at down to 25% of full power. That is, it can ramp at 80 MW per minute. So, your understanding about nuclear not being able to load follow is incorrect. http://www.areva.com/EN/global-offer-419/epr-reactor-one-of-the-most-powerful-in-the-world.html
5. The ideal arrangement needs no fossil fuel. It is about 75% nuclear and 25% pumped hydro. Before we get to that stage we can use fossil fuel. The link in #3 above shows this situation for France. Scroll down to see the fossil fuel usage and the CO2 emissions. The French system with close to the current proportions of technologies has been running for about 30 years and has the lowest CO2 emissions from electricity generation of any of the major economies. The system is proven, safe, reliable and low cost. Australia could meet the current demand in the NEM with 25 GW of nuclear and 8GW of pumped hydro (excluding reserve capacity margin). 8GW of pumped hydro could be provided for around $15 billion by building the pumped hydro capacity and using existing dams – such as explained here: https://bravenewclimate.com/2010/04/05/pumped-hydro-system-cost/
6. Solar thermal is not economic – not even close. I expect it never will be. See here: https://bravenewclimate.com/2010/04/05/pumped-hydro-system-cost/ (down load the pdf version to see the foot notes and appendices) and https://bravenewclimate.com/2010/04/05/pumped-hydro-system-cost/
7.
I’d suggest the economically viable solution is nuclear 75%, hydro and pumped hydro 20%, gas 5% and perhaps some wind if it is economic, although I wonder if that will ever be the case. Wind is not economic in the France case, so why will it be economic anywhere? However, if renewables can provide a component economically then of course it should be part of the mix. But, we should not mandate a role for renewable energy. At the very most non-hydro renewables may provide 10% economically. I don’t believe 20% can be achieved economically. So why are we spending so much of our time and resources talking about renewables, which may make up 10% to 20% of the final solution, whle we spend nest to no time on the solution that will provide around 7% of a low emissions solution?
8. You are correct that the solution will not be all or nothing. Unfortunately, in Australia the environmental NGO’s and two of the three major political parties are opposed to nuclear power at all – the Labor party, which is currently in Government with the Greens, has opposed nuclear for about 50 years. Meanwhile all the research and subsidies pour into renewables for no result. This has been going on for decades. So while you say ‘it is not all or nothing’, most of the people who make that very statement want to focus all their effort on renewables and want nuclear to remain banned or at least given no support.
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Neil Howes 30 May 2011 at 5:55 PM
NEM wind farms are spread over an area 1200 km east-west by 800 km north-south. All of them combined produced zero or less than zero output on 65 5-minute periods in May 2010. The capacity factor from all NEM wind farms was about 2% for 6 days. The real data shows that the output of your modelling does not agreew with the real world evidence.
You say:
So you are arguing for curtailment, are you? If so, you need to use in your calculations capacity factors for the system, as distinct from individual wind farms, closer to 20% than the 30% commonly claimed by the wind power advocates..
Please tell me about economic “local storage”.
Neil, I suggest it is time to stop spreading FUD and confusion about wind power. Comment that state a fact here and a fact there but do not relate them with a total system and a total cost of electricity for the whole system, are simply causing confusion and misleading readers.
Please provide a cost estimate for the system you propose that is capable of supplying the power quality and reliability we demand.
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Thank you for the corrections on the load-following abilities of newer nuclear designs – that does change the picture markedly. I will read the references.
And sorry for being a newbie here and thus not being fully up on threads that have gone before. There is a lot to take in.
I can see that the Australian situation is a very interesting one. One of the few places where there is enough space and resource for renewables to actually be physically plausible, but also a large uranium resource so nuclear is practical too, but a political concensus on ‘no nuclear’ which must be very frustrating.
As you emphasise, effectiveness and cost effectiveness are really important, and if renewables are neither then it makes little sense (and more importantly won’t have the desired outcome) to persue them exclusively.
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I had an interesting conversation with my mechanical engineering friend currently doing a long grant with NRC. This guy said a year ago that the U.S. was going full bore natural gas. This looks to be about right, though there will be many battles over fracking.
I asked him what he thought of the german plan to phase out nuclear and he said they would indeed go ahead with this, but would be forced to invest, along with other solvent countries like the Scandinavian ones, heavily into something like Desertec. He acknowledged that german solar was no good; thought german wind no good.
I asked him if Desertec would provide base power (thus massive storage requirements, etc). He said no, nuclear would do this…
but obviously not german nuclear. I realize this has a peripheral relation to CO2 avoidance. Sorry.
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Wookey,
@ 31 May 2011 at 11:46 PM,
You are very welcome. Yes, there is an enormous amount of material on BNC. Look first to the list of posts on the “Renewable Limits” tab to see posts grouped in a sort of order.. The TCASE series provide valuable background.
You said:
There are other reasons too why intermittent renewables are not as effective as many would like to think they are. One of them is the amount of resources require – e.g. around ten times as much steel and concrete, and therefore water used during construction, per MWh of electricity generated, as nuclear and fossil fuel generators. The CO2 emissions, and the fatalities, involved in material extraction, processing, fabrication, transport, construction, maintenance and decommissioning are therefore higher than for nuclear for the same electricity output. This component of the CO2 emissions is not mentioned in the article because the emissions from nuclear and renewables (excluding the back up component) are both small (negligible) compared with fossil fuels.
Regarding solar thermal, this comment may be of interest: (ref. https://bravenewclimate.files.wordpress.com/2010/01/lang_2010_emissions_cuts_realities_v1a1.pdf )
That provides a bit more food for thought that is often not considered.
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Please read the below article which explains in detail the CO2 reduction due to wind power and some of the associated costs.
http://theenergycollective.com/willem-post/57905/wind-power-and-co2-emissions
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Willem Post,
Willem,
Thank you for your comment. The paper you linked to is interesting and explains much about the effects and complexity of including wind generation in an electricity grid. I commend the linked article those who are interested in the subject.
This sentence jumped out at me because it gives two points for comparison with the Inhaber curve:
Converting to SI units:
CO2 emission reduction of 0.272 tonne/MWh at 3.2% wind [energy] penetration
CO2 emission reduction of 0.187 tonne/MWh at 20.9% wind [energy] penetration
For the Australian NEM, assuming the average emissions intensity of 1 t/MWh, the above figures, converted to percentage so they can be compared with the Inhaber vertical axis, are:
CO2 emission reduction of 27% at 3.2% wind [energy] penetration
CO2 emission reduction of 19% at 20.9% wind [energy] penetration
For comparison, the Inhaber equation gives:
CO2 emission reduction of 69% at 3.2% wind energy penetration
CO2 emission reduction of 3.0% at 20.9% wind energy penetration
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Peter, i had provided exactly that link a while back. (as others have, even further up)
but i disagree with your conclusion and calculations. the article contains this part:
—
“Because the annual-average CO2 emissions of the NEEG is about 1.0 lb of CO2/kWh (low compared to other grids due to CO2-free nuclear and hydro power), wind proponents claim a CO2 emissions reduction of 1.0 lb of CO2/kWh of wind power, whereas it is (1.0 – 0.539) = 0.461 lb of CO2/kWh, significantly less than claimed. ”
—-
so 100% reduction would be 1.0 lb of CO2/kWh.
now when this “study finds 0.413 lb of CO2/kWh at 20.9% wind power “, this would translate into something close to a 50% reduction. (actually 41.3% at about 20% wind penetration)
why does your conversion to the other units give a completely different result?
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sorry, basically all math in my post above was completely wrong. (it is still early over here)
100% reduction would be 0.0 lb of CO2/kWh
(or so 100% would be 1.0 lb of CO2/kWh.)
so if emissions drop to 0.413 lb of CO2/kWh would give about a 60% reduction.
please feel free to correct all my other (and the new?) errors in my post above…
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A 1000 MW coal plant produces about 3 million lbs of CO2 every hour.
Ref: http://www.powermag.com/environmental/Alstoms-chilled-ammonia-CO2-capture-process-advances-toward-commercialization_86_p4.html
That would be 3 lbs per kilowatthour. I have checked this number from chemistry and its a good value. Most of the quotes on the interenet are for too small an amount of CO2, such as the 1 lb/kwh sod stated above. In order to determine the effectiveness of wind at reducing CO2 you would need an hourly dispatch model for a region, such as Australia or Texas and simulate a historical recent year in retrospect, while dispatching all the generators with their limitations such as ramp rates and reserve levels. Whether a coal plant could be taken off line would depend on the reliability of the wind forecast and the reliability and cost of quick startup generation. Its not a trivial problem. I don’t think the CO2 redution numbers can be arrived at correctly until simulated in an hourly model for a previous year or years. Once simulated then a trend could be noticed and put in a simplified equation. However it would be very regional specific.
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(Comment deleted – violation of the citation rule. Please re-submit with refs.)
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“That would be 3 lbs per kilowatthour. I have checked this number from chemistry and its a good value. Most of the quotes on the interenet are for too small an amount of CO2, such as the 1 lb/kwh sod stated above.”
——-
thanks for your replay Gene. you are right in your description of what must be done to fully assess CO2 under certain levels of wind penetration.
the article which was linked first by others, then by me, gives an explanation for the low CO2 number:
—
“Because the annual-average CO2 emissions of the NEEG is about 1.0 lb of CO2/kWh (low compared to other grids due to CO2-free nuclear and hydro power)”
—-
so the number is low because it is an average, which actually includes low CO2 emitters like nuclear and water.
i think the estimates of the CO2 output of the gas plants used in the scenario in the article are good:
———
“CCGT Heat rate = (3,413 Btu/kWh)/efficiency 0.55 = 6,205 Btu/kWh
CO2 emissions/kWh = 117 lb of CO2/(million Btu x 1 kWh/6,205 Btu) = 0.726 lb of CO2/kWh
OCGT Heat rate = (3,413 Btu/kWh)/efficiency 0.35 = 9,751 Btu/kWh
CO2 emissions/kWh = 117 lb of CO2/(million Btu x 1 kWh/9,751 Btu) = 1.141 lb of CO2/kWh
————
http://theenergycollective.com/willem-post/57905/wind-power-and-co2-emissions
as we can see, even replacing those coal plants with these gas plants would be a good idea. (while looking at CO2)
the study then looks at different efficiencies of those gas plants, under different speeds of wind change.
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I’m not so sure Sod, there are indirect emissions from methane than escapes the drilling rig, or that is uncombusted through the turbine (methane tends to not burn completely in engines because of its narrow explosion range).
Here’s a high estimate, there are others that are lower, though in all cases the methane emissions are a big factor (methane being 20x more potent a GhG than CO2 molecule for molecule)
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Somebody whose name escapes me has pointed out that fugitive methane could cancel out the CO2 savings of burning gas rather than coal. If methane has a warming potential of 25 and 2% escapes while gas fuel saves 50% of CO2 we have
(2% X 25) + 50% = 100% back to same as coal.
Odorants have been added to NG since this incident http://en.wikipedia.org/wiki/New_London_School_explosion
However it ‘wind fuel’ advocates are correct synthetic methane can be made with high EROEI so protocols would have to be implemented to minimise fugitive release. Note that some methane (usually under 10 ppm) is in our breath all the time.
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“’m not so sure Sod, there are indirect emissions from methane than escapes the drilling rig, or that is uncombusted through the turbine (methane tends to not burn completely in engines because of its narrow explosion range).”
————
Cyril i agree. the article mentions it, but i am not sure whether it is factored into the CO2 calculation (Co2 equivalent?)
this is a very serious problem with gas. especially as the release of methane often happens in another country, and in russia it might be hidden much more easily. anyway, it will often produce greenhouse gases that will not be factored into the calculations, which is a very bad thing. there is a lot of cheating going on, whenever government money is involved.
even if it might sound different at times, i am not a big fan of gas. it has a lot of disadvantages, but also a few advantages. in Germany Greenpeace energy is currently pushing “wind gas” which might be one of the most easy ways of storing alternative electricity. (simply because it can go directly into the gas network, which has a pretty immense storage capacity.
http://www.greenpeace-energy.de/windgas.html
but is your argument about the about 50% CO2 reduction at wind penetration of 20% in this article, that it doesn t factor in methane release? or is my calculation wrong?
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@ Gene Preston,
///In order to determine the effectiveness of wind at reducing CO2 you would need an hourly dispatch model for a region, such as Australia or Texas and simulate a historical recent year in retrospect, while dispatching all the generators with their limitations such as ramp rates and reserve levels.////
Can’t we just do it by counting how many coal plants are shut down because of wind? How about we ask this question: how many coal plants have been shut down in Australia because of wind? That ought to be simple enough.
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Hello Sod, those calculations above are in the right ballpark, for CO2 from combustion only.
It just occured to me, that throttling gas turbines more, as in the case of a big wind grid, increases the amount of methane that is unburned. We must also factor in the indirect energy use for e.g. transporting the gas. Pushing gas through pipelines over thousands of miles or liquefying it and putting it into a big ship, requires a surprisingly large amount of energy, and most is in the form of electricity (compressors) that has to be generated by burning even more natural gas.
Then there should be a CO2 equivalent lifecycle per kWh emission number resulting from all this. But it appears this was not done in the previous analysis.
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This explains how CO2-e emissions are calculated in accordance with the UN Framework Convention on Climate Change:
Click to access national-greenhouse-factors-july-2010-pdf.pdf
Other web pages on the DCCEE web site explain the difference between life cycle emissions, fuel cycle emissions and fuel combustion emissions. Life cycle emissions are not used because they lead to too much problem with duplication. So Fuel Cycle emissions are used. There are Scope 1, Scope 2 and Scope 3 emissions factors.
All these measures do not properly account for emissions due to jerk from wind power.
Australia does not measure emissions from generators. It calculates them based on the emissions factors given in the document linked above. (http://www.climatechange.gov.au/~/media/publications/greenhouse-acctg/national-greenhouse-factors-july-2010-pdf.pdf ). These are the emissions factors DCCEE instructs everyone to use to maintain consistency. However, I believe they are not even close to being correct. I suspect the factors given in this document http://www.aemo.com.au/planning/419-0035.pdf are probably more accurate for the overall average emissions factors per generator unit. But these do not allow us to calculate the effect of cycling.
This tells how Ireland calculates emissions from electricity generators. This also does not allow for the effect of jerk. http://www.eirgrid.com/operations/systemperformancedata/co2intensity/
I expect the methodology used in Ireland is standard for EU.
That leads me point again to this excellent French web page (for those who haven’t seen this before):
http://www.rte-france.com/fr/developpement-durable/maitriser-sa-consommation-electrique/eco2mix-consommation-production-et-contenu-co2-de-l-electricite-francaise
Scroll mouse left an right across the stacked area chart and watch how the pie chart below changes to show the proportions of the different generator types. Scroll down further to see the CO2 emissions.
This page clearly shows what we should be striving for if we want low emissions: 75% to 80% nuclear, most of the remainder hydro and pumped hydro, and a bit of gas.
If we had that mix and electricity was cheap as it is in France (near the cheapest in Europe), then nuclear could replace gas for heating and, as it gets cheaper still, it would begin the transition of transport from fossil fuels (to electric vehicles and/or to fuels produced using cheap electricity). Furthermore, with cheap clean electricity, we’d be able to offer to assist developing countries to implement cheap clean electricity instead of fossil fuel generated electricity.
The key to all this is cheap electricity. Therefore, carbon pricing aimed at raising the cost of electricity is exactly the wrong policy.
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Peter I suggest part of the reason for millions in poverty is because fossil fuels have always been artificially cheap. World population got so large because of unsustainable expectations. Wiki suggests synthetic nitrogen fertilisers enabled a third more of us than otherwise. In round figures that would be 4.7 bn not 7 bn. Therefore the low cost of energy, not the high cost up til now has been part of the problem.
On CO2 intensity obviously technology and auxiliary demands must make a large difference. With hard black coals we have pulverised, gasified and supercritical. The cooling could be immersion, evaporation towers or air radiators. I was surprised to see the Engineering Toolbox gives 2.3 kg CO2 per kg of bituminous coal under lab conditions but 2.8 kg CO2 for a kg of natural gas. This shows combined cycle burning of gas must be quite efficient..
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That seems wrong, natural gas has a considerable combustion value in hydrogen content whereas bituminous coal doesn’t. This is a big factor for natural gas lower combustion CO2 emissions, the second factor being efficiency (45% heat to electric for modern pulverized coal plant, 60% heat to electric for latest CCGT).
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Coal plants routinely shut down for a number of reasons. You would not be able to tell if coal plants are shutting down because of wind by looking at historical data. Possibly gas prices dropped and made coal unattractive for a period of time. Or there have been maintenance needed on a coal plant. Or there could have been an line out of service that made running the coal plant un economical.
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John Newlands,
That is what I would call an unsubstantiated personal belief. Furthermore it flies in the face of all evidence.
Cheap electricity (along with good governance and other important factors) is a key factor that creates increasing wealth (for a country) which means better systems for health, education, infrastructure (sewerage, roads, public transport, law and order, etc), housing, employment opportunities, polution control and a fulfilling life.
Here is my link (where is yours?):
1. Wealth and Health of nations http://www.gapminder.org/world/#$majorMode=chart$is;shi=t;ly=2003;lb=f;il=t;fs=11;al=30;stl=t;st=t;nsl=t;se=t$wst;tts=C$ts;sp=5.59290322580644;ti=2009$zpv;v=0$inc_x;mmid=XCOORDS;iid=phAwcNAVuyj1jiMAkmq1iMg;by=ind$inc_y;mmid=YCOORDS;iid=phAwcNAVuyj2tPLxKvvnNPA;by=ind$inc_s;uniValue=8.21;iid=phAwcNAVuyj0XOoBL%5Fn5tAQ;by=ind$inc_c;uniValue=255;gid=CATID0;by=grp$map_x;scale=log;dataMin=295;dataMax=79210$map_y;scale=lin;dataMin=19;dataMax=86$map_s;sma=49;smi=2.65$cd;bd=0$inds=;example=75
2. Life expectancy versus electricity use per person:
http://www.gapminder.org/world/#$majorMode=chart$is;shi=t;ly=2003;lb=f;il=t;fs=11;al=30;stl=t;st=t;nsl=t;se=t$wst;tts=C$ts;sp=5.59290322580644;ti=2008$zpv;v=0$inc_x;mmid=XCOORDS;iid=tiVeyAJd7iRWorOwl%5FARWEQ;by=ind$inc_y;mmid=YCOORDS;iid=phAwcNAVuyj2tPLxKvvnNPA;by=ind$inc_s;uniValue=8.21;iid=phAwcNAVuyj0XOoBL%5Fn5tAQ;by=ind$inc_c;uniValue=255;gid=CATID0;by=grp$map_x;scale=log;dataMin=5.6;dataMax=50083$map_y;scale=lin;dataMin=19;dataMax=86$map_s;sma=49;smi=2.65$cd;bd=0$inds=
3. Income per person versus Electricity use per person:
http://www.gapminder.org/world/#$majorMode=chart$is;shi=t;ly=2003;lb=f;il=t;fs=11;al=30;stl=t;st=t;nsl=t;se=t$wst;tts=C$ts;sp=5.59290322580644;ti=2008$zpv;v=0$inc_x;mmid=XCOORDS;iid=tiVeyAJd7iRWorOwl%5FARWEQ;by=ind$inc_y;mmid=YCOORDS;iid=phAwcNAVuyj1jiMAkmq1iMg;by=ind$inc_s;uniValue=8.21;iid=phAwcNAVuyj0XOoBL%5Fn5tAQ;by=ind$inc_c;uniValue=255;gid=CATID0;by=grp$map_x;scale=log;dataMin=5.6;dataMax=50083$map_y;scale=log;dataMin=282;dataMax=119849$map_s;sma=49;smi=2.65$cd;bd=0$inds=
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Peter I’ve independently concluded that the world has too many people as have many others. I see no way the the bottom billion in India, Africa and China can make it to what I call the ‘5 kw lifestyle’. It is thought half the nitrogen in human protein has a synthetic origin, see 3rd paragraph in http://en.wikipedia.org/wiki/Haber_process
Since most urea and ammonia currently derives from natural gas that seems to imply mass starvation when gas runs out.
I say fossil fuels are artificially cheap because they
don’t pay their clean up costs. If markets were truly far sighted they should have seen the CO2 problem coming back in the days of steam trains and set some money aside for fuel replacement. Now billions think cheap energy is their birth right..
MODERATOR
John – you are slipping off topic here into the realms of philosophical discussions of the “big picture.” Please continue on the Open Thread 15.
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John Newlands,
I am not sure how much of what you say is tongue in cheek. But I’ll answer it seriously.
The points you make have an effect on me that is the opposite of what I think you would like. The effect is:
1. I think the people that express such beliefs are way out on the fringe. To me they are like the people who take on extreme religious beliefs. I then tend to apply the halo effect to all their beliefs and those who hold similar beliefs. I then tend to discredit the beliefs of the groups that hold such beliefs. Sorry, but that is the effect it has on me.
2. I wonder why the people who think the world is over-populated don’t draw straws amongst their family members to decide who should commit suicide.
3.
Why pick on fossil fuels? Why not pick on everything else and make your decisions in a properly balanced and rational way. I don’t buy this irrational approach to picking on fossil fuels. As far as I am concerned, fossil fuels are fantastic. Thye should be used until we will allow better alternatives. The benefits fossil fuels bring to humanity are enormous. I expect any attempt to internalise more of the externalities would do more harm than good. That is where I’ve come to. Until we are prepared to remove the impediments that we have placed to obstruct the technologies society doesn’t like (through environmentalists’ irrational beliefs), then I would not support adding more irrationally driven “solutions” (such as taxing energy).
MODERATOR
Peter – see my comment to John – this is veering off-topic – take it to the Open Thread 15 which is where discussions on “big picture” philosophies and politics belong. Thank you.
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Changing tack somewhat I’m inclined to agree that carbon tax may degenerate into a farce. On ABC Landline they discussed ‘carbon farming’ with a specific example of a pig farm. By covering the effluent sludge pond with a tarp and burning the methane they get a credit under the carbon tax scheme.
That is completely misguided in my opinion. For starters c.t. wasn’t supposed to have offsets or credits hence it would be simpler to administer than an ETS. However I think the starting position must be zero entitlement of CO2e. Large intensive animal farm pay c.t. either on CO2 at $20-$30/t or CH4 at $400-$600/t based on 20X equivalence. Flaring clearly works out cheaper so there is the benefit ie carbon tax reduction. If you then give a saleable carbon credit for that flaring you’ve counted the benefit twice.
I fear this is the kind of muddled thinking we will see with other parts of carbon tax. Our major efforts should go to shutting down Hazelwood and saving millions of tonnes of primary CO2. Instead we will be preoccupied the minute side issues of pig poo and the growth rates of trees. While I think carbon tax is the right game rules the umpire just isn’t tough enough in enforcing those rules.
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John,,
I agree with you. There are so many problems with carbon pricing and from my perspective, it is totally wrong approach. We can’t even measure the damned stuff, as this thread has made absolutely clear.
We should instead focus on removing the many impediments that distort the energy markets and especially favour some technologies and disadvantage others. Clearly the biggest disadvantages are to nuclear.
While we allow those impediments to remain in place, I cannot take seriously any of the proposed carbon pricing. In Australia carbon pricing is clearly political. It is clearly just another opportunity for redistributing wealth. The proposed carbon pricing scheme can have no effect whatsoever on world emissions. But it will seriously damage our economy if the carbon price has to rise high enough to achieve the 2020 emissions targets. While we muck around with this nonsense and at the same time ban what is potentially the cheapest way to cut emissions, we are wasting our wealth and time.
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Peter Lang,
Below is my article “Wind Power and CO2 emissions” on THE ENERGY COLLECTIVE.
I have made some revisions and additions.
Wind Power Penetration and Costs
A spreadsheet of 0.5% to 20.9% wind penetration was prepared to illustrate the rapid increase of wind accommodation costs with increasing wind penetration; the 0.5% corresponds to the about 239 MW of wind capacity currently on the NEEG and the 20.9% corresponds to the 10,000 MW wind capacity of this study.
According to ISO-NE personnel, 0.5% wind penetration, the current condition in the NEEG, is not noticeable. However, this lack of “notice” is inexcusable, because, based on the above calculations, the NEEG fuel costs are increased by about $10.05 million/yr and the corresponding NEEG wind power accommodation fees should be about $13 million/yr, as the spreadsheet shows.
Right now, the wind power facility owners feeding into the NEEG are paying NOTHING, because it is not “noticeable.”
The above indicates wind power facility owners are getting a huge free ride by using the “spare” cycling capability of the existing grids but not fully paying for all the cycling costs.
The above indicates utilities and the ISO-NE have not identified, quantified and included all the cycling costs in their current wind accommodation fees. Studies, based on actual operating data, need to be made to better determine all the owning and O&M costs of cycling to accommodate wind power.
Willem Post
I can’t send you the spreadsheet because I don’t have your email address.
http://theenergycollective.com/willem-post/57905/wind-power-and-co2-emissions
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This is a fascinating illustration of several big-picture principles I’ve been struggling to discern! Thank you so much.
1) People easily get lost in detailed analysis that is immaterial to the big picture.
[Lots of arguing over detailed numbers. Peter Lang steps back and demonstrates that you can pick any reasonably possible set of empirical data and you’ll still discover wind is a too-costly way to mitigate CO2.]
2) With too many trees, it is easy to obfuscate the forest (or perhaps to fool ourselves about what the forest looks like.)
[Goggins, sod, et al argued that Colorado (where I happen to live) provides empirical proof that increased wind leads to reduced CO2. Hawkins provided a link to Boone’s demonstration that Goggins hid the elephant in the room: imported power. Was Goggins ignorant or purposeful? I don’t care: he was wrong. A simple conclusion for reader: caution about detailed claims is warranted until we can be confident there are no elephants around the corner.]
A personal conclusion: this is a great illustration of how helpful it would be to develop visualization tools that make it easy to honestly illustrate uncertainty (fuzziness), while still displaying the features that are true independent of uncertainties. Lang’s analysis shows that whether the multiplier is x3 or x100, wind is hugely costly compared to alternatives. I want to reflect on how best to visualize such an outcome in a way that allows the details to fade into the background while highlighting the underlying reality.
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I have added the below section to the Summary of my article
http://theenergycollective.com/willem-post/57905/wind-power-and-co2-emissions
Making Wind Facilities More Grid-Friendly
Ways for wind facility IPPs to minimize the fees would be to install
their own cycling facilities at a suitable distance from their wind
facilities to provide cycling energy BEFORE the wind energy enters the
grid, i.e., be grid-friendly.
In New England, this would avoid most of the $19 billion to $24
billion of overlay grids and avoid a significant visual impact. It
would also avoid the difficulties and costs of accommodating wind
power into the existing electricity generating and T&D systems.
The production, MWh/yr, of the combined facilities would be at least 3
times that of only the wind facilities and the overall cost/kWh would
be about 40 to 50 percent less than from only the wind facilities.
IPPs would generate a significantly greater percentage of the
electricity in the US.
Modern wind turbine facilities could be designed to present less
variable output to the grid, such as by feathering their rotor blades
to limit minute-by-minute ramp rates of their output, at moderate
reductions of production and at moderate additions to capital costs.
Ireland enacted a new grid code in 2004 that requires wind turbine
facilities to reduce the variability of their outputs, i.e., be more
“grid-friendly.” See Page 17 of
Click to access david.white.wind.co2.saving.12.04.pdf
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In a Business Spectator KGB interview with ACIL Tasman CEO Paul Hyslop, referring to Mandatory Renewable Energy Targets, Hyslop states:
http://www.businessspectator.com.au/bs.nsf/Article/KGB-Paul-Hyslop-pd20110616-HVAU4?OpenDocument
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Willem Post. MrPete and Graham Palmer,
Thank you for your comments. I’ve been away and no internet access so only just seen them.
Willem, I’ll read your update in slow time.
I’d like to add to Graham Palmer’s comment:
Correct! The Howard government’s targets were “Clean Energy Targets” not “Renewable Energy Targets”. The target was a more realistic, but still ambitious, 15% cut on 2000 emissions by 2020. The Clean Energy Targets did not discriminate against nuclear (although the many impediments to implementation in Australia would still have had to be removed). Howard then put nuclear firmly on the table with the Ziggy Switkowski Task Force and its 2006 report “Uranium Mining, Processing and Nuclear Energy”. The government then promoted it strongly. As usual, the Labor Opposition took the opportunity to run a negative, scaremongering anti-nuclear campaign about “would you want a nuclear power station in your suburb?”
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harrywr2, on 18 June 2011 at 2:29 AM said:
@Eclipse Now, on 11 June 2011 at 10:52 AM said:
He shows a graph from U.S. northwest of all wind farms falling flat for ten days…..As far as I am aware, the NorthWest is NOT really on the ‘wind-map’ of America!
There have been various reports out of the UK that their wind turbines experienced extended periods of inactivity as well.
The US PNW makes for a reasonable ‘test bed’ for Wind Farms, as much of the storage and transmission systems that a simple ‘back of the envelope calculation’ would indicate were needed already existed.
The wind farms in the US PNW produce fairly close to ‘as advertised’. The numbers I’ve seen(sorry no link) are 28-34% on an annual basis.
If you view this wind map…http://rredc.nrel.gov/wind/pubs/atlas/maps/chap2/2-01m.html
there is a ‘dark section’ along the Washington, Oregon border…this area is the Columbia River Gorge where the Columbia River cuts thru the Cascade Mountain Range…that’s where the majority of windmills are located. It’s an exceptionally good site as it is a wind tunnel.
http://rredc.nrel.gov/wind/pubs/atlas/maps/chap2/2-01m.html.
It is true that the best wind in the US goes down the east side of the Rocky Mountains.
According to the specification sheet for GE Wind Turbine operating temperatures are -4F to 104F with a ‘survival’ limit of -22F to 104F
Click to access Application%20Appendix%20C.pdf
It gets colder then -22F in Wyoming.
http://weather-warehouse.com/WeatherHistory/PastWeatherData_CasperNatronaCntyIntlArpt_Casper_WY_January.html
Wyoming, Montana and the Dakota’s are not particularly hospitable to man or machine.
The point being that ‘how much wind’ is available is only one of the determinants for suitable siting. A place with long hard Winters with long sustained periods of sub freezing weather is going to pose additional challenges to Wind Farms.
It is true that T. Boone Pickens built a 10 GW wind farm in Texas.
Here are the 2009 Texas Generating Capacity Statistics.
http://www.eia.gov/cneaf/electricity/st_profiles/sept04tx.xls
9,600 MW ‘other renewables’(wind) generating capacity.
9,600 MW * 8760 hours = 84,096,000 MWh per year at 100% capacity.
Here are the 2009 Texas Energy Generation Statistics
http://www.eia.gov/cneaf/electricity/st_profiles/sept05tx.xls
21 million megawatts of ‘other renewables’ was what was actually generated. A 25% capacity factor. If I use end of year 2008 wind generating capacity then the capacity factors rises to 31%.
Slides 14,15 and 16 from the Texas Grid Operator are interesting.
http://www.ercot.com/content/meetings/ros/keydocs/2011/0113/08._PDCWG_Report_to_ROS_January_13_2011_rev1.ppt
Excellent wind in the spring when system loads are low and not very good wind generation in August when system loads are high.
It would appear that the Texas seasonal problem coincides with the Pacific Northwest seasonal problem.
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Willem Post,
It would be handy to know how the NEEG data you have compares with the points charted in Figures 1 in the lead artice to this thread. Could you provide, for NEEG, the % wind energy penetration and the % emissions avoided by wind generation (per MWh of wind generation).
I wonder if you could also provided the cost per tonne CO2 avoided as well as explain the methodology you use to calculate it and assumptions and sources for the data used in the calculation.
I think this may be of interest to BNCers and may elicit discussion.
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Peter,
NEEG wind energy penetration is about 0.5% of 130,000 GWh/yr.
The average NEEG emissions is about 1.0 lb of CO2/kWh.
According to ISO-NE personnel, wind energy till now has not been noticeable, meaning nothing is being measured, just the way wind facility owners like it.
My calculations indicate at the planned (pipe dream) 20.9% penetration it is (1- 0.59, due to extra cycling CO2) = 0.41 lb of CO2/kWh
Below is a new article
http://theenergycollective.com/willem-post/59747/ge-flexefficiency-50-ccgt-facilities-and-wind-turbine-facilities
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Hi Willem,
Thank you for the extra information. To make it easier for me and BNC readers to understand, without having to read between the lines amd do conversions, could you present the figures in a way that can be directly compared with the lead article, especially Figure 1 and also Cost per tonne CO2 avoided ($/t CO2 avoided).
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It may be of interest to readers in Australia and elsewhere that there is actually a legal challenge to the renewable energy policy in Europe now under way at the United Nations Economic Commision for Europe. Essentially the EU has ratified the Aarhus Convention, which relates to Human and Environmental Rights. In particular in relation to Access to Information, Public Participation in Decision-Making and Access to Justice in Environmental Matters.
Policies CANNOT be developed on political consensus or ‘group think’. They have to be developed in a structured manner, the public has to be informed so that they can participate in the environmental decision making. Finally they have to have access to a legal review procedure, which is fair, equitable, timely and not prohhibitively expensive, to challenge acts or omissions of the authorities.
The targets developed in the EU, namely a 20% reduction in greenhouse gas emissions and 20% of energy to be derived from renewable sources, were solely based on political consensus. No proper technical, economic or environmental assesment was completed. These then became mandatory under the relevant Directive, which each Member State being assigned a mandatory target based on existing renewable energy penetration and a factor based on GDP. Each Member State had then to develop a renewable energy action plan, one can go into the EU Commission’s website and see: http://ec.europa.eu/energy/renewables/transparency_platform/action_plan_en.htm
Namely that Section 5.3 on impacts, such as quantities of greenhouse gases avoided and jobs created is for most Member States bank (Ireland, Netherlands, Sweden, Denmark, France).
This is a complete breach of the structured environmental assessment required by the UNECE. For a renewable project of this nature one needs to know:
• What are the environmental objectives? In particular, exactly what quantity of greenhouse gas reduction is being achieved over the situation of no wind energy on the grid, versus the level that has now been installed and the level which is projected to be installed?
• What were the alternatives considered to achieve those objectives, for instance could greater use have been made of energy efficiency projects, as has been pointed out time and time again by the engineering profession?
• What would be the state of the environment without implementation of the plan? The key aspect here is what damage exactly is carbon dioxide causing? This has to be quantified.
Of course none of this has been done, officials have bypassed legally binding procedures, hence the legal case which has been taken by the UNECE Compliance Committee.
http://www.unece.org/env/pp/compliance/Compliance%20Committee/54TableEU.htm
Note in case ACCC/C/2008/32 the Compliance Committee ruled in May 2011 that the EU needed to reform its legal access, such that citizens could challenge acts of omissions by EU institutions in relation to environmental matters.
So there are interesting times ahead in this legal challenge. Bottom line, it is not about political consensus, instead the environmental costs, benefits and alternatives have to be assessed and determined to be appropriate before the policy or programme can be implemented.
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Pat Swords
Thanks you for keeping us informed of the progress of this EU court action and what it means for investment in wind generation in Ireland. This is highly relevant to the situation in Australia too. We are progressing along a similar path in Australia.
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Below are the websites of two articles relating to Peter Lang’s article.
The articles have been revised due to comments, additional information, etc.
http://theenergycollective.com/willem-post/57905/wind-power-and-co2-emissions
http://theenergycollective.com/willem-post/59747/ge-flexefficiency-50-ccgt-facilities-and-wind-turbine-facilities
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The current renewable programme in Ireland is for 40% of our electricity to be renewable, essentially over 37% from wind. This is an illegal programme, never having being properly assessed or developed through proper public participation in decision-making procedures at EU or National level. It involves circa 8,200 MW of wind and a minimum two new interconnectors to the UK. Projected costs are over €30 billion and it is unlikely from a technical point to ever work with any degree of reliability.
Now for the potential upside, the country is completely and utterly broke. The population voted in a new Government, totally obliterating the Irish Green Party, who were in charge of Energy and the Environment from 2007 until early 2011. For the first time people are starting to be receptive to hard questions, for instance I have included some recent quotes below from the official report into our banking crises, which firmly put the blame on ‘groupthink’ and ‘herding’. The Western World’s infatuation with renewable energy, particularly wind, is in fact little different and will in time be every bit as devastating.
So we do potentially have a window of opportunity here in Ireland, but we must use it carefully. With a lot of hard work I have reached the situation in which the UN is investigating the EU with regard to compliance with the Aarhus Convention on Access to Justice, Public Participation in Decision-making and Access to Justice in Environmental Matters. This will lead to the EU getting a reprimand for pursuing what are illegal programmes in relation to renewable energy. However, this all takes time as legal cases move in a slow defined manner. But when it does occur it is binding and will have legal effect.
With regard to public opinion, our opportunity is to present a clear, logical case to the public, based on value for money and real environmental benefits, rather than perception and spin. This means documents going into the public domain about the wind energy programme in Ireland must be of a good quality. Unfortunately several public bodies have, for undoubted political gain, been issuing non-transparent information on the environment, i.e. false publications to the public, an example will follow in another e-mail. This leaves an uphill battle.
It is clear to us that the EirGrid CO2 emissions on the web are a simplification of actual figures and under reporting annual verified data. However, if people want to use them as indicative figures, then there maybe some merit. While Joe Wheatley hasn’t finished his work on this, what he appears to be demonstrating is that the data is showing a significant decrease in emissions avoided as the penetration increase (Consistent with the trend indicated by the Inhaber paper). To us this is the important point, wind will be reasonably effective at reducing CO2 with low penetration, but at the point of investment we have now reached it is proving ineffective and if further investment continues, there will be little or no gain. This is the message we need to get out.
The fact of the matter, as we all realise, is that politicians and other forces are pushing this renewable agenda without any proper assessment of its technical, economic or environmental impacts and effectiveness. Nowhere in the world has a proper study been completed as to what the carbon emissions on a national grid would be without and with various levels of wind investment and penetration. Not only does the Irish grid offer some unique aspects, because of its relatively manageable size and availability of accurate data, but there are also legal aspects related to compliance with EU legislation and the United Nations Economic Commission for Europe’s Aarhus Convention. These legal aspects will come to the fore over the latter part of this year as compliance investigation ACCC/C/2010/54 progresses and may well lead to the position that an independent study can be developed.
[1] http://www.unece.org/env/pp/compliance/C2010-54/Communication/Annex%203%20(a-c)%20file%20on%20EU%20Ombudsman/FinalSubmissionComplaintToEUOmbudsmanMay2010.pdf
[1] http://www.bankinginquiry.gov.ie/
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Back before Easter, it emerged in comments here that there is no direct measurement of greenhouse gas emissions at the smokestacks of our Australian fossil fuel power plants. (See here for discussion.) Emissions are calculated from average intensity factors, which are open to manipulation, and which can’t capture reduced efficiency when responding to variable demand.
I remain astonished by this. In the midst of the political hot potato of the day, the carbon tax “debate”, no-one in the media seems to have twigged to the fact that we don’t actually have direct data on GHG emissions from power generation. The data that we have is inadequate for the purpose of formulating policy, be it carbon pricing or future energy generation.
Good data is the sine qua non for participatory democracy, and
particularly now as we are making very large policy decisions about
energy. We need to be collecting and reporting empirical data on emissions and on energy production from all modes of generation. The data and the methodologies need to be in the public
domain. Private operators should not be exempted from reporting performance for commercial-in-confidence reasons.
Who’s going to be the first reporter, or the first member of the opposition, to ask Greg Combet or Julia Gillard or Bob Brown why we’re talking about a carbon tax when we’re not measuring our emissions?
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Pat Swords and John Morgan,
Thank you for these excellent and pertinant comments. What could be more important than these issues before we comit to damaging our economy with a flawed carbon price scheme?
I find it dissapointing that there is little discussion on BNC about these issues that Pat Swords and John Morgan have raised. I wonder why BNCers avoid the real elephant in the room – the flawed carbon pricing scheme. It is flawed for many reasons, and Pat Swords, in several comments on this thread, and John Morgan have raised some important ones.
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Bonnevile Power(the primary grid operator for the US Pacific Northwest) has some interesting new slides up in relation to our wind experience.
Slide 5 shows a substantial ‘seasonal’ capacity factor’ difference for wind. (45%+ in May, 20% in December)
Slide 12 shows the plan for finally getting rid of our stinking coal plants.(1% of the solution involves renewable’s)
Click to access WIF_SC_Presentation_6-11.pdf
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See figure 2 here: http://www.clepair.net/windstroom%20e.html
It shows carbon content of the fuel used to generate electricity in Denmark is decreasing, but the CO2 emissions per kWh of electricity generation is not decreasing as fast. The authors suggest the explanation is that wind farms are causing fossil fuel generators to cycle so that the emissions savings are less than anticipated. The authors claim:
“Wind does not save fossil fuel, therefore does not reduce CO2 emissions.”
The trend is similar to what the Inhaber paper shows. I haven’t compared numbers.
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Peter Lang, on 26 June 2011 at 4:17 PM said:
See figure 2 here: http://www.clepair.net/windstroom%20e.html
. The authors suggest the explanation is that wind farms are causing fossil fuel generators to cycle so that the emissions savings are less than anticipated. The authors claim:
Here is a study on fossil fue fired cycling O&M Maintenance costs. Of note is that it is estimated a ‘cold start’ on a 1,000 MW coal fired plant costs $70,000 in ‘excess wear’.
Click to access 35.pdf
Obviously, a plant operator is going to avoid shutting down completely unless there are reasonable assurances that the plant won’t be needed for an extended period of time.
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harryw2,
Good point. For other readers I’ll mention that David Walters and others have said similar in numerous previous comments on BNC. They have pointed out that gas turbines can start and stop a maximum of 3 times per 24 hours, othewise they breach warranty conditions with the manufacturer. (I understand newer versions are improving on this but there is still a cost to stops and starts and someone has to pay. So there is a tendancy to keep running, keep burning some fuel, and therefore keep producing CO2 when backing up for wind generation. This is the point made in the Inhaber paper and in the link in my previous comment.
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harryw2, thanks for putting a number on that: $70k/cold start/GW.
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I have just received three emails from people who contributed on this thread. I’ll post them in separate comments below It is unfortunate there was little discussion of their previous comments on this thread; it seems they are no longer contributing here. That is a pitty because this subject should be of real interst to BNCers, especially given Australia’s ongoing committment to subsidising renewable energy, particluarly wind power.
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Effect of Windpower on fuel consumption & CO2 emissions in Ireland
In an email just received, Hugh Sharman says:
Hugh Sharman attached a power point paper called Effect of Windpower on fuel consumption & CO2 emissions in Ireland. The Conclusions say:
Note that this empirical data study corroborates the Inhaber curve (see Figure 1 in the lead article above).
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Kent Hawkins (see his earlier comments on this thread) said:
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Pat Swords said (in an email circulated tonight)
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To provide some background, the Irish grid is modern and functions perfectly well without a single wind turbine or an expansion in our high voltage grid. Now we have a Government plan for 40% renewables by 2020, which involves four thousand wind turbines (about 8,000 MW) and a doubling of our high voltage grid by an additional 5,000 km. This will destroy our landscape and our economy, we simply cannot afford the cost which is well over €12 billion and likely to exceed €30 billion. So why are we doing this? Is it to save CO2 then how much and with what effect?
For over a decade the EU and Member States have been promoting renewable energy, the target is now for a 20% reduction in greenhouse gases, 20% renewables and 20% energy conservation by 2020 (20-20-20 by 2020). If one goes into the Renewable Energy Action Plans for the Member States to achieve this, see below, and starts with Denmark, going to Section 5.3 of the plan on impacts (page 111 of 123), then it can be seen that the table which quantifies greenhouse gases and job savings is blank. Why? Because under the EU regulation for these plans it is an optional section.
http://ec.europa.eu/energy/renewables/transparency_platform/action_plan_en.htm
Nothing unusual there, one can go into the plans for Sweden, Finland, Austria, France, Italy, the Netherlands, Ireland, etc, all blank. A few countries, such as Germany, at least tried to put some figures in here. However, are these for real?
If we take Germany there is an English summary of the Renewable Energy Plan of the Federal Environment Agency now out. Nowhere does it state the economic costs or justification in terms of quantified environmental benchmarks
Click to access 3997-0.pdf
A great plan from a country, which can transform itself (economic ruin and massive destruction to its landscape) on nothing but glossy brochures. On page 8 of the Plan it states that 3,000 full load hours can be expected as an average for onshore wind, this equates to (3,000/8,740) x 100 = 34.2%. In reality in Germany onshore wind load factors are between 18 and 22% at best, so the actual electrical output has been increased by a factor of more than 50%. In fact if one looks at the German wind energy association’s own figures for 2010, the load factor was 15.7% (http://www.wind-energie.de/infocenter/folien/bwe-statistiken-2010).
There are laws against all of this; Germany is a Party to the Aarhus Convention, which requires in Article 5 (2) that each Party shall ensure that the way in which Public Authorities make environmental information available to the public is transparent. Energy, cost /benefit and other economic analysis all fall under the term information on the environment. Pillar I of the Aarhus Convention, on access to information on the environment and its correct dissemination, is enacted in Germany by the Umweltinformationsgesetzt (UIG): http://www.gesetze-im-internet.de/bundesrecht/uig_2005/gesamt.pdf .
Section 7 (3) is clear in that official information on the environment has to be up to date, exact and comparable. Yet we have the Federal Environment Agency with its ‘evangelism’ deliberately in an official policy document inflating the performance of the wind energy sector and its potential by more than 50%.
This is not an idle issue, there are massive costs and abuses occurring in the resulting subsidised ‘pyramid schemes’ that have been created. Already renewable energy in Germany has in 2011 added €11 billion to the electricity bills. Small and medium sized companies cannot carry the additional five and six figure sums that have been added to their bills. German industry is divided, see below, there are those who have operated sustainable long term businesses, who will not be able to survive the massive rise in electricity costs and then there are those who blatantly intent to profiteer from the distorted market which will arise.
http://www.spiegel.de/international/business/0,1518,771309,00.html
There is only one way this whole thing will end, that is clear. However, it has been fueled by a failure of senior elected and non-elected officials to comply with procedures, which were legally binding on them. We have an electrical supply system which has worked well for decades, if they want to change it and pass enormous costs to the citizen, both financially and in damage to the landscape and environment, then they have to justify it and follow the correct procedures, in particular the Principle of Proportionality in which the financial or other burden placed on the citizen must be minimised and commensurate with the aim to be achieved.
So where is the damage cost for CO2 to justify these massive costs for its reduction? Neither is there any quantification of what CO2 will be saved.
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Pat Swords,
You have made it clear – again – just how bad this mess is. And we are in an even worse position in Australia.
I’d encourage BNCers to get involved in this critical debate – so that, hopefully, the debate moves from emails to the BNC web site where everyone can follow it and get involved. (I received 12 emails over night from around the world and from a range of perspectives (including a gas generator manufacturer).
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Peter and Pat
These are great posts and I am one BNCer who is very interested in this issue. I have long held doubts whether wind or solar could provide electricity for a modern society and reduce GHG emissions, cost effectively. About 20 years ago I visited Rottnest Island, which at that time had a lone wind turbine on an island noted for its strong, consistant winds. While I have no details I remember being shocked by the high cost of installation and relatively low capacity factor and thus low power output. For two years I have been visiting this site and from the real world data presented it is becoming obvious that even after 20 years of further wind development nothing has changed.
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I received 18 emails overnight on the Ireland wind power and EU renewable energy issues. Here is the first:
Will Post asked
Utility economist-engineer replied:
It’s a pity the discussion is not taking place on BNC.
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Another comment from Mark Lively, Utility Economc Engineer:
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From Pat Swords:
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Some folks might be interested in FOE’s current statements on emissions reduction in response to a Yass wind farm meeting :
http://www.yasstribune.com.au/news/local/news/general/passions-run-high-at-wind-farm-meeting/2217616.aspx
&
There has already been this comment posted on Yass Tribune by Neil Rankine :
“withouthotair’s comment that wind is ineffective at reducing CO2. His link is to a nuclear advocacy website concerns me, as does Barry Brook’s advocacy for nuclear. Lets look at some unbiased investigation into this. Sinclair Knights Merz produced a peer reviewed (by UNSW Global) study that found there was no problem for the existing grid to scale wind up tens of times what it is now, and that every megawatt hour of electricity that wind puts into the grid offsets between 1.0 and 1.6 tonnes of CO2. This is higher in some instances than Latrobe Valley emissions that are being avoided.”
So the discussion is entering into the territory of this thread, as this page is being referred to in the comments at those two sites. I have brought up the SKM study before, there is one for NSW and one for Victoria that I know of:
Click to access SH51906_SKM_MMA_Final_report.pdf
&
http://www.environment.nsw.gov.au/climatechange/greenhousegassavingstool.htm
This report is being heavily touted by a number of people, as well as NSW previous gov, and still available under the new gov.
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Hi Bryen,
Thank you for that information. Regarding the Victorian study by MMA. I’d refer readers to this comment by Martin Nicholson and to the related comments that follow:
MMA (now part of SKM) has a history of providing the answers the Greenies want to hear. They have always hated nuclear and provided misleading modelling results to support their case. The Australian Greenhouse Office (now the Department of Climate Change and Energy Efficiency) often used MMA as one of the three modelling groups it contracted to provide comparative studies. The others were ABARE and ACIL-Tasman. I’d wouldn’t place much value on the MMA info.
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Greens chap Neil Rankine just posted this :
The Sinclair Knight Merz report was reviewed by UNSW Global, authored by Hugh Outhred:
Click to access MMA_Report_peer_review.pdf
It confirms the abated emissions by installing wind into existing generation mix are very high as in SKM report. Obviously as wind gets to 20% of supply you do have to make changes to the mix of generation, grid changes, etc. Solar would smooth this well.
——–
at:
http://www.yasstribune.com.au/news/local/news/general/wind-farm-protest-to-heat-up-in-yass/2212088.aspx?page=3
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[…] […]
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Here are two posts just released regarding CO2 emissions avoided by wind generation in the EirGrid:
http://joewheatley.net/emissions-savings-from-wind-power/
http://www.clepair.net/IerlandUdo.html
This is an extract of an email just received:
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Pat Swords sent the following (see his earlier comments on this thread for background):
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Peter Lang, interesting. I just read a piece by Giles Parkinson in Crikey that claims wind in EirGrid has led to a fall in wholesale power prices:
I’d be interested in your take on the argument he makes.
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Handing back wind power subsidies through price cuts in order to stay in business could be an example of what is sometimes called dissipation of rent. Therefore in the long run the price cuts won’t exceed the subsidy. I’d call it not-quite-negative-pricing.
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Peter Lang’s interesting finds about the Irish grid led to
Bentek Corporation: How less became more; Power and Unintended Consequences in the Colorado Energy Market.
http://www.bentekenergy.com/WindCoalandGasStudy.aspx
which (in the so-called executive summary) suggests the problem is due to coal burner cycling and recommends increased use of natgas units.
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John Morgan,
Thank you for your question and comments. I haven’t had a chance to investigate and won’t have for a while. However, this email just came to me this morning from Willem Post (see his previous posts on this thread for background), and has some relevance to your question (and to David Benson’s comment):
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John Morgan, there are a number of things in that piece I can’t comment on – because I am in Ontario, Canada, but …
The pricing of the market has little to do with the technologies, or even that the topic is energy. The sentence in the article you linked to that shows this, inadvertently, is:
“Not only has wind reduced imports of brown-coal generation from Victoria, it has also, counter-intuitively, reduced the need for peaking plants for much of the year — although not, it should be noted, at times of the highest peaks caused by extreme heat waves, when wind has mostly absented itself.”
So we know that supply has been added, and it sounds like the supply that has been added cannot displace existing capacity, which exists to meet the peak demand wind is expected to be absent for. Adding any supply quicker than demand is increasing will lower prices.
So here is where that takes the market. You lower one market price by creating other markets. Nobody is going to invest in a plant to meet only the capacity of peak periods when they only have a market when the wind isn’t blowing and demand is there. In the US and Europe, there is increasing discussion of capacity markets – where suppliers are paid to be available. In my province, which is aiming to eliminate coal in the next half decade, the CCGT plants appear to have Net Revenue Requirement contracts – which is a capacity payment. At a minimum, this has to become a market for the MWh, plus a market for capacity.
Here’s how that has worked out in Ontario, with our very dysfunctional market. When demand rises sharply, due to either heat or cold over an extended time, the rates drop noticeably (as more coal and gas become part of the mix, and both essentially already have the plant paid for – so they can bid just above the operating costs).
Lower market prices for more expensive generation simply is not sustainable – it is instinctively obvious.
The Oxford study, from a recent comment, noted that wind output depresses market pricing, and, in heavily grid-connected Europe, that included neighbouring jurisdictions. The exception was the NordPool area, which includes the large Norwegian hydro reservoirs. They can buy at depressed prices during windy times in the southern jurisdictions, and sell into the higher prices of lulls.
But those southern jurisdictions are having new supply built not by a market – but by subsidies of one sort or another.
Lastly I’ll note my own bungling efforts with Ontario data. It’s not an easy subject to communicate, and I’m not well equipped to do so, but I will argue a heavily subsidized wind industry must lead to a heavily subsidized gas industry. It has where I live.
http://morecoldair.blogspot.com/2011/06/searching-for-value-in-ontarios.html
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I’d be extremely interested to see the detailed emissions accounting for the Irish grid.
They appear to have an interesting suite of plant to respond to support wind;
http://en.wikipedia.org/wiki/List_of_power_stations_in_the_Republic_of_Ireland
Including a superb (and paid for) 292MW pumped storage facility
http://en.wikipedia.org/wiki/Turlough_Hill
I’m familiar with the Alstom engineering that is the 435MW single shaft machine at http://www.esb.ie/main/about-esb/aghada.jsp It has a very flexible (and efficient) performance range for such a large CCGT.
Downloading some of their data (wind contribution and demand), it would seem they have some difficulty with wind forecasting. It’s not clear where the numbers come from and how far ahead they are prepared but they are certainly significantly at variance to those which some of our clients work with.
Would it not be important to understand the cost of fuels. How much does indigenous peat cost per kWh? Cheap, but filthy? Would their wind integration strategy weight CO2 reduction as more important than fuel importation?
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Here is the direct link to the Inhaber study:
http://www.sciencedirect.com/science/article/pii/S1364032111000864
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The paper by
Herbert Inhaber
Why wind power does not deliver the expected emissions reductions
linked just previously may be behind a paywall. The conclusions are highly similar to the two Irish studies linked previously by Peter Lang and the Bentek Energy study also previously linked.
However, the study suggests that even natgas fired units have difficulty adjusting to the combined ramping (cycling) of wind and actual demand.
I tentatively conclude (once again) that only quite a modesst contribution from wind power can be economically accommodated, irrespective of net CO2 savings (which anyway are highly anti-correlated with thermal generaiton wastage of fuel).
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David B Benson,
Please see the lead article for this thread concerning the Inhaber paper and the relevance to renewable energy policy and carbon pricing policy.
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Peter Lang, on 9 September 2011 at 11:43 AM — Thank you, I already have. To the economic extra cost, please add the three sources of environmiental concerns known to me (which may only be siting issues):
(1) NIMBYs — Some concerns are justified;
(2) Raptors and other birds — Of regional concern here in the Palouse region of the Pacific Northwest;
(3) Bats — which should be of deep concern elsewhere in at least the USA.
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David B. Benson, on 9 September 2011 at 10:54 AM said:
However, the study suggests that even natgas fired units have difficulty adjusting to the combined ramping (cycling) of wind and actual demand.
I tentatively conclude (once again) that only quite a modest contribution from wind power can be economically accommodated, irrespective of net CO2 savings (which anyway are highly anti-correlated with thermal generaton wastage of fuel).
This may be valid for a very small geographic area ( such as Eire) where one site contributes >25% of wind capacity.
Larger geographic spread of wind farms( for example the Eastern Connector in US or the NEM in Eastern Australia) both about X50 times larger area, result in much lower ramping rates of wind output. In the NEM, 1600MW of capacity spread over 15 locations has changes in output of 1-5%/h much slower than the response time of natgas units.There is a good reason for this, weather fronts bringing rapid changes in wind velocity, can travel across Eire in tens of minutes, but take hours or days to travel across continental land masses.
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Neil Howes, on 9 September 2011 at 12:41 PM — Most electric power does not actually travel very far, so you’ll have to work harder to convince me of that (presumed) geographic effect; I can be persuaded. On the other hand, find the quotation from “Power” magazine that Peter Lang posted.
Regionally, not even Bonnevile Power Authority’s massive hydro capability could fully manage around 4.3 GW [nameplate] wind but now that BPA only needs to balance around 3.5 GW wind there no longer appears to be a problem.
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David B. Benson, on 9 September 2011 at 12:53 PM said:
Neil Howes, on 9 September 2011 at 12:41 PM — Most electric power does not actually travel very far, so you’ll have to work harder to convince me of that (presumed) geographic effect;
For those in NE of US, some power is coming from northern Quebec James Bay Hydro, and for those in California from the hydro in Washington, Idaho etc. These a vast distances compared to the size of Eire.
The issue I was addressing was the fluctuation of the output from one wind farm or a few clustered in a small region, compared to the more steady ( mins to hours) output of the NEM wind farms covering 1200 x800km region.
Regionally, not even Bonnevile Power Authority’s massive hydro capability could fully manage around 4.3 GW [nameplate] wind but now that BPA only needs to balance around 3.5 GW wind there no longer appears to be a problem.
With >10GW of hydro the problem has never been evening out fluctuations in 3-4GW wind, its always been TRANSMISSION capacity to export to California when river flows are high.
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Scott Lufti @ 8 September 2011 at 10:53 PM,
Thank you for that excellent explanation. In short “there is no free lunch”. Wind energy, with an LCOE three times that of basload generation, cannot reduce the cost of electricity over the long term. Furthermore, wind adds other costs: e.g. the higher cost of transmission and the additional O&M costs the fossil fuel generators.have to carry and eventually pass on in higher electricity prices.
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Relevant to the discussion above is an email I received today from a USA utility engineer. His email was in response to a discussion about nanotube energy storage and I sent the link to this excellent comment by John Morgan: https://bravenewclimate.com/2011/06/29/open-thread-17/#comment-131710
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Thanks Peter. Even John Morgan may be too optimistic; the costs of maintaining and replacement of the storage system is likely at least as big as the capital investment in terms of cents/kWh levelised cost!
The cost of just replacing lead acid batteries, that are actually much cheaper than the 100 USD/kWh target, is greater than the cost of generating electricity with natural gas or coal! That’s just for the replacement only!
If bulk electricity storage is going to work it has to cost less than USD 50/kWh, last decades and have near zero maintenance cost.
Here’s some backup to these statements for both wind and solar plus storage costs in an excellent energy paper from Bill Hannahan:
http://www.coal2nuclear.com/energy_facts.htm
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Also, for a feel on the perspective of the requirements for energy storage wind interemittent energy sources such as wind and solar, see these calculations:
http://www.theoildrum.com/node/8237
Basically we don’t have enough lead to build the required battery. Off by a couple orders of magnitude, in fact.
So you can’t build the battery. Guess what’s going to fill in the gap when its rainy, snowing, cloudy, nighttime, evening and morning, and in winter, basically most of the time. Fossil fuels of course! Oops!
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Cyril R, @ 9 September 2011 at 8:50 PM
Thank you for that interesting quote. However, I think it may be even worse than even Bill Hannahan says:
This https://bravenewclimate.files.wordpress.com/2009/08/peter-lang-solar-realities.pdf provides another take on how much solar capacity and how much storage capacity is needed (based on acutal output at 30 minute intervals over 2 years from one PV power station). To meet the Australian National Electricity Market demand with solar power and pumped hydro energy storage would require:
This is a limit analysis. We would never build such a system and dispersal of sites would mean the worst case capacity factor would probably not be as bad as from this single site. However, the limit approach used here does help to clarify the issue that Bill Hannahan has discussed.
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“Because to cover any meaningful portion of the gaps in wind generation you would need at least 24 hours of storage, and the cost of the storage can’t represent too much of a multiplier over the cost of the generation facility.”
CSP w/storage is the ideal fit for capturing additional wind contribution as the output of the CSP plant can be “time shifted”, plus the type of steam turbine used calls for a completely variable/responsive output.
Storage dramatically lowers the delivered cost of CSP because it more than doubles the plant capacity factor.
“….complete wind/storage/gas system would cost….”
Less than one might think, if the gas is part of the CSP w/storage system.
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Scott Luft, thanks for your detailed response.
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@ Cyril R and @ Peter Lang
What possible value is there in that Bill Hannahan thought bubble?
I respectfully suggest, the only PV-everywhere-with-storage proposals that exist come from proponents of nuclear power. They are quite deliberately intended to look ridiculous.
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Zvyozdochka, no numbers no argument. PV doesn’t add up. A little PV with lots of fossil adds up. Electricity must be supplied reliably and continuously, if you have no PV and you can’t make a battery that costs trillions then fossil must – and will – step in.
Energy analysis is about numbers and making these add up. Like Peter says these solar and wind calcs is a ‘limit analysis’. Not meant to suggest this is to be done, rather the opposite: PV and wind are so rediculous that we simply won’t do it. What we’ll do is burn fossil whenever the sun and wind aren’t there. Which is 80-90% of the time. And now we have also learned that our fossil generators are less efficient so the savings are not even that lousy 10-20%.
What we are looking at is fossil lock-in. I’m sorry that we do, but we do. PV and wind are the bubbles, as Bill Hannahan’s article inescapably concludes.
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It only took a few minutes to unravel the statistical trick being used in Fred Udo’s attack on wind in Ireland, posted by Peter above. This appears to be a classic case of a lurking (or confounding) variable being used to misleadingly present correlation as causality; a comparable example is arguing that cigarette lighters cause lung disease since people who buy them tend to develop lung disease. In this case, the lurking variable that is the actual causal factor appears to be cold weather and its impact on heating demand, data that is available but that (for reasons we can only speculate) was not used in these correlational analyses.
What tipped me off was part 3, Figure 3 of Mr. Udo’s text, where he called out an event in Ireland around June 9-12, 2011, when the carbon intensity of Ireland’s electricity production surged. I was curious as to what might have caused that event so, on a hunch, I pulled weather records for Ireland. Sure enough, there was an abnormally cold spell when temperatures fell into the 30’s and 40’s F, 10 to 20 degrees below normal for that time of year. Aha! Cold temperatures drive heating demand, forcing Ireland’s numerous fossil-fired combined heat and power (CHP) plants to fire up and run at a high level of heat production (and subsequently more emissions per megawatt-hour, MWh, of electricity, since CHP plants relative to the rest of the fleet are not optimized for electricity production, and CHP plants being run to produce maximum heat are not being operated in a way that is optimized for electricity production; moreover, it appears that the emissions associated with heat production are rolled into the data that Mr. Udo is using, so a CHP plant producing only or mostly heat and little or no electricity under cold conditions like these would score at infinite emissions/MWh). A smaller possible factor is that higher demand for electric heating drives higher merit order, less-efficient fossil plants to operate to meet the abnormally high electric demand.
As one would expect, cold spells and home heating demand often correlate with high wind speeds, which is how Mr. Udo was able to draw his false conclusion that wind was the causal factor. Sure enough, a closer examination of the spikes in emissions/MWh in his data show that all are associated with cold spells, and only some are associated with an increase in wind output. It doesn’t take a statistician to tell you which is the causal factor in that relationship. Had Mr. Udo himself been more interested in finding the actual causal relationship at play here, he might have noted that the correlations between wind output and emissions intensity varied widely from month to month (as one would expect for weather-driven seasonal changes in electric demand), usually a strong indication that another variable may be the actual causal factor.
I should also point out that, contrary to Mr. Udo’s claims, the method Irish utility system operator EirGrid uses to calculate emissions savings from wind is accurate. The plant-specific heat rate curve that they are using would account for all of the impacts wind energy would have on the efficiency of the fossil fleets under all operating conditions.
There’s a large, well-established body of empirical evidence showing that as states like Colorado and Texas have added wind energy to their grids, their carbon dioxide emissions decreased by even more than had been expected. That data was used to directly refute an erroneous study by consulting firm Bentek even before the study came out 18 months ago, and the Bentek study has since been widely dismissed as the fossil fuel industry attack piece that it is, except for continued efforts by the fossil fuel industry to continue spreading its misinformation.
There are also dozens of power system studies conducted by utilities, government agencies, and independent grid operators showing that adding wind energy to the grid results in as large or larger emissions savings than the 1:1 offset commonly expected, largely because additional wind energy forces inflexible coal plants to be taken offline for extended periods of time and the share of their output not directly replaced by wind is replaced with more flexible and cleaner natural gas generation. I won’t waste time repeating the full discrediting of the Bentek study that has already taken place, but you can read through that with the numerous links below:
http://www.renewableenergyworld.com/rea/news/article/2010/09/the-facts-about-wind-energy-and-emissions
Click to access 04_05_2010_Colorado_emissions_response.pdf
http://www.awea.org/newsroom/realstories/The-Facts-about-Wind-Energy-and-Emissions.cfm
Click to access 110720-The-Facts-about-Wind-Energy-and-Emissions.pdf
Michael Goggin,
American Wind Energy Association
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Michael Goggin, it is good to see the people in the wind industry admit that wind is a horrible natural gas lock-in. It is somewhat pleasing for me to see people in the american wind industry not being able to come up with a plan to use less natural gas in the US, but it also worries me. Claiming that replacement of coal with natural gas reduces emissions and then putting that savings on the balance of wind is dishonest at best. We need a plan to use less natural gas.
By the way, CHP in Ireland is only a small portion of the electric pie. This doesn’t explain the large deviances in fuel savings relative to wind kWhs.
Click to access CHP%20in%20Ireland%202010%20Report.pdf
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Finding an expectation these states exceeded is a feat.
Well done Mr. Goggin.
I’ve done a quick format of emissions data for TX, CO, IA (Iowa has IWTs as the greatest % of its total capacity), plus the US total, and put them in a google doc here: http://tinyurl.com/3qrnwl7
No significant wind capacity state performs above the national average for either CO2 on SO2.
Texas is a nice example of something, but not of reducing emissions.
The US EIA has a nice little blurb here on their August experience.
http://205.254.135.24/todayinenergy/detail.cfm?id=3010
People can look up the wind output in Texas, graphed to system load, by picking the dates (August 11 is a good one) out of the zip folders at http://www.ercot.com/gridinfo/generation/
What you’ll find is the average daily wind output remained inversely related to demand most days throughout the record of heat of August.
You’d find enormous prices, and you’d find not only large production from existing ff plants, but also mothballed coal plants being spurred back into service.
It sure looks like they would have been a whole lot better investing on cleaner supply that could match peak demand, – as opposed to new idle IWTs matched up with aging coal.
I don’t see how you separate IWT’s and ff’s – I do see how Texas produced the AGW denialist governor with his sights on the presidency.
Again.
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Michael Goggin calls attention to the spike in CO2/kWh around 1/4-hour 1100 in June 2011 that Fred Udo also noted. Goggin, however, stretches it to last 4 days so that he can explain it away as corresponding to a cold spell, but it clearly lasted less than an hour.
Furthermore, Udo only calls attention to it as evidence of the responsiveness of the 1/4-hour data. His analysis is based on scatterplots, so the effect of outliers is minimized.
And Goggin has no basis for asserting that Udo’s is wrong that the CO2 data do not account for extra emissions due to ramping. Eirgrid clearly states that they base their emissions data only on each plant’s generation rate over the 1/4-hour and its established efficiency at that rate.
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Mr. Goggin is entirely off on a tangent with his correlation/causation rant. Strong negative correlation between wind and demand over time stands alone as testament to wind’s low value to tax and rate payers. No causation is implied or needed. The cause is negative correlation and the effect is wasteful spending on mostly unschedulable and highly variable wind energy supplies – and higher rates over time.
Here in Ohio we have introduced a bill in the Senate to REPEAL THE RENEWABLE MANDATE, and experts from all corners are converging to educate the public and lawmakers as to why they are correct to undo the law put in place barely three years ago.
Michael, you’d better get out here because I don’t think Dana can handle all the smoke and mirrors by herself! Or maybe Denise can come on her way back from speaking at the ANGA convention… Word here is the gas industry does not need wind even though you need them.
(Deleted personal comment)
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@ Martin Nicholson: “With a relatively small amount of wind power the capacity credit can be close to the capacity factor, but as the penetration increases, the capacity credit falls because the total network impact from the loss of the wind will be that much greater. The amount of CO2 abatement from wind is related to the amount of fossil fuel generation that is replaced. The capacity credit is theoretically the amount of generation that can be replaced.”
I think we have to bridge a gap in understanding here. A small penetration of wind as % of energy demand over time will have a greater ratio of CV to CF than a large one – in a given geographic region, but it will never be close to the CF. PJM allows a generous 12% CV upper limit for bidding into year ahead planning and day ahead capacity markets – and the penetration of wind in PJM is very low, less than 2%, while the ACF is between 25 to 28%
And I would argue that capacity credit is the theoretical (statistical) minimum contribution to PEAK DEMAND that is expected.
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Neil Howes, on 9 September 2011 at 5:47 PM — Yes, transmission is a limiting factor, but is the response rate of the hydro turbines. [I assure you I follow BPA quite closely.]
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@ Cyril R
“What we are looking at is fossil lock-in.”
Only if you think like a “baseload(er)”.
If I have a suite of supply; private PV, industrial PV, onshore/offshore wind, CSP w/storage, geothermal, hydro, interconnects plus some gas backup/boost (on site with CSP), it’s no technical challenge to get a stable/responsive supply system.
Work for our clients suggests it’s possible to push down fossil fuel use to less than that used to supplement the current base load design peaks.
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