Bishop Hill Wind produces more CO2 than gas - the numbers
Aug 18, 2012 Energy: gas Energy: wind Ever since Gordon Hughes' report noted that wind power was more likely to produce more carbon dioxide emissions than gas, I have been looking for the figures behind the claim. In the comments, someone has now posted some details that seem to meet the bill. Although these are not Hughes' own numbers -they were submitted in evidence to Parliament by an engineer - I assume they are similar.
[A]s wind rarely produces more than 25% of its faceplate capacity it needs 75% backup - which due to the necessity of fast response times needs OCGT generation (CCGT can respond quickly but the heat-exchanger systems upon which their increased efficiency relies, cannot - so CCGT behaves like OCGT under these circumstances). CCGT produces 0.4 tonnes of CO2 per MWh, OCGT produces 0.6 tonnes. Thus 0.6 tonnes x 75% = 0.45 tonnes. Conclusion: Wind + OCGT backup produces more 0.05 tonnes of CO2 per MWh than continuous CCGT.
Now, where does the alternative view - the one proclaimed by Grantham Institute man Robert Gross - come from?
Bishop Hill
Tim Worstall has picked up on this post. There is an interesting exchange in the comments.
Reader Comments (57)
Forty years ago I was an interested colleague of a chap who worked on wave power. His basic argument was irrefutable: wind power is too dilute - in time and space - to be of any practical use for electrical generation. He hoped that wave power, which is much denser, might prove practical. I've not kept in touch, but get the impression that it's the very density of wave power that is the problem - the equipment has to withstand a hell of a battering.
I don't think that it's lunatic to entertain hopes for solar power, but it is for wind power. Just bonkers. Or very, very stupid. Or dishonest.
Read about the situation in the Netherlands by scientist Kees le Pair:
http://www.clepair.net/CBS-aug2012nl+eng.html
There was an actual saving in the Falkland Islands. They were using diesel generators which output more CO2 than coal, let alone gas. Even so the CO2 reductions 3.8% with 13% wind electricity weren't very good.
The figure for OCGT is a little lower than usually accepted; many would use a figure of 0.7.
There is also the problem that using OCGT in standby mode, i.e. with some of the gas turbines running at synchronous speed and low output, so as to provide the necessary rapid response, generates CO2 without corresponding electricity.
Also, running Open Cycle turbines for long periods raises the maintenance cost quite substantially. The cost of the electricity from OCGT then becomes close to that from wind, i.e. bloody expensive.
Here's another one from the Netherlands:
Wind turbines increase fossil fuel consumption & CO2 emission.
on:
http://www.clepair.net/windSchiphol.html
The base report for this is the empirical data from Fred Udo using Irish data: http://www.clepair.net/IerlandUdo.html
The problem is that he was looking at a system with different types of standby generators, but Figure 7 is instructive. At 30% wind penetration, you use 30% more fuel per kWhr. Add in the CO2 cost of the windmills and you don't save CO2.
I have also seen a US report on Colorado and Texas which claims that CO2 increases above a very low penetration, similar for Ontario. The key issue appears to be the type of plant. Some CCGTs have to be run at 60% capacity to be usable with the steam cycle as standby. The manufacturers now provide gas bypass to heat the boilers also clutches so you can decouple the steam turbine. Such systems operate at 40% efficiency in the OCGT format. The gas heated boiler type can spin up much more rapidly than the full OCGT. Tube boiler coal systems and CANDU can operate at 20% output whilst giving rapid spin-up
This is an odd argument. It seems to start from faceplate capacity. Surely it should start from actual generation?
The argument seems to be that the turbines only deliver some percentage, say 25%, of faceplate. Therefore we need fossil fuel generation for the other 75%, and this means CO2 generation.
The corollary of this argument is that the article appears to consider the cost of the generation at faceplate. This leads to the conclusion that wind generation only costs double that of conventional plants.
Maybe I have misunderstood the argument. If this is right however, a better form of the argument from the same observations would be that wind power is 4-5 times more expensive (because we would be measuring actual generation, not faceplate). Then we would only consider the CO2 output which is required to make this amount of generation viable, in the form of backup conventional plants.
The real problem with wind is that if the market was free, no supplier would ever buy from a wind power generation company, because they cannot guarantee product quality - the supply fluctuates too much. If the supplier then has to buy gas generators and install them as well, he would speedlly find that the smart thing to do is run the generators more efficiently and dispense with his turbine plans.
The part of the argument about the efficiency of gas powered generation in an intermittent scenario is very interesting.
The public policy prescription must be: stop all subsidies for power generation. Free the utility companies to buy from the suppliers of their choice. If that is done, solar and wind will both wither on the vine, at least until the costs of other generation methods rise very substantially.
The CO2 argument in the UK is very strange. The argument for lowering UK CO2 emissions must be that it will affect global warming. However, according to the IPCC sensitivity estimates, even were the UK to vanish totally taking all its emissions with it, there would be little or no effect on warming. So that cannot be why we are doing it.
Are we maybe doing it to set an example that others will follow? If so, what is the evidence that doing that will be effective in motivating China and India and the US?
The argument 'do it because if everyone did it things would be better' is a very odd one, when there is no evidence that they are actually going to do it, and when doing it ourselves makes it no more likely they will.
Picking up litter may set an example in our community and make others more careful. Stopping smoking may set an example and be good for us. Public honesty may set an effective example. These are all cases where we can show actual or likely influence as well as effects on a real problem. Doing something others think idiotic, and which will have no effect on the supposed problem? It smacks more of obsessive hand washing.
All analysis of the impact of intermittent wind power show that the CO2 emisions savings are about zero or are actually increased because of its effect on operation of back-up power stations.
The Government admits it doesn't know, as the following response to an FOI request by John Etherington shows:
This is fairly typical of UK Governments. No due diligence. Ministers with no clue as to what their policies will do. Corrupt lobbying.
Well done Andrew for spotting that.
The use of the term "back-up" for CCGT electricity generation capacity perforce creates entirely the wrong impression, i.e. that wind is the primary and gas the secondary source of energy. As CCGT would under the Windmill Plan be producing 75% of the power then gas is the primary and wind the secondary by a mile. In a sense wind is more like the back-up to gas, a back-up however which is uncontrollable, completely superfluous and one which does nothing other than end up wasting enormous quantities of gas fuel every year. The Windmill Plan is therefore above all a scheme for supplying energy needs by gas, supplying those needs grossly inefficiently, and with a overall capital expenditure more than an order of magnitude (!) greater than is necessary. Nothing less than undiluted madness.
michel: the purpose of the windmills is not to save CO2. it's to provide carbon trading/offset receipts for the banks and to support the Euro by a non-national taxation. There is also the political narrative: they are like the Easter Island Statures, a symbol of the power of the ruling elite whilst the workers willingly toil at green jobs.
To that extent, they are the direct descendant of the swastika, the symbol of the domination of the first green religious socialism, Nazism. Basically when they are plastered all over our land and power is rationed to those favoured by the state, we'll be a subordinate region of the Greater Reich which may then be centred in Turkey,
For homework read about the Thule Gessellschaft and the lives of Dr. Hjalmar Horace Greeley Schacht, Prescott Bush and Sir Montague Norman.
The above calculation seems to me to significantly understate the cost disadvantage of wind power. The assumption is that, as wind generates an average of about 25% of its nameplate capacity, that 75% backup is needed. But surely the required backup is close to 100%, to cover for the inevitable periods when the wind output is close to zero.
Furthermore, even when not required OCGT turbines must be kept spinning, using fuel and producing CO2 for no power. Surely this cost must be directly added to the cost of windpower - and in a fair marketplace, would have to be paid for by the wind producers, who are the only beneficiaries.
Instead they receive a subsidised premium price for their sub standard, non dispatchable power. Allowing the market to set a fair price for windpower, including letting these costs fall where they lie, would very quickly expose the stupidity trying to return to a power source rejected in the 1850's.
The original statements from BH will not stand up to any serious examination.
Windmill CO2 savings are reduced not just by lack of availability, but also inherent variability of output and inability to provide the various response services our island grid requires. CCGT plant could provide both response and reserve - the steam range of the plant can match coal fired performance, including coal's inability to provide sustained response (for which you need a Dinorwig). Providing these services through CCGT operation at below full power uses more fossil-fuel because the plant operates below optimum efficiency (and with increased maintenance costs). The reason why the CO2 reductions that follow from using windmills are reduced is then through the provision of many varied ancillary services to the grid by fossil-fueled plant each of which is difficult to evaluate.
The conclusion that the CO2 reductions of windmills are poor is almost certainly correct. It follows, of course, that the fossil-fule bill for a windmill scenario will be much the same as it would be for a non windmill scenario. In which case, why build the windmills in the first place?
@Graeme
"There was an actual saving in the Falkland Islands. They were using diesel generators which output more CO2 than coal, let alone gas. Even so the CO2 reductions 3.8% with 13% wind electricity weren't very good."
The key point for Falkland Islands wind power is that provision of diesel fuel is very difficult. It has to be expensively shipped in - (not, of course, from Argentina!) - and sometimes stormy weather delayed shippings. Under those circumstances, diesel fuel is at a premium, and ANY way of saving it is worth doing...
michel said:
I agree. The plans to install 30GW+ of wind in the UK are not with the intention of getting 30GW of output. The backup generation will surely be in order to ensure the expected power (whatever that actually is but let's say 30% of faceplate) is actually available whether it is windy or not.
@michel
"The CO2 argument in the UK is very strange. The argument for lowering UK CO2 emissions must be that it will affect global warming. However, according to the IPCC sensitivity estimates, even were the UK to vanish totally taking all its emissions with it, there would be little or no effect on warming. So that cannot be why we are doing it...."
We are doing it:
a) because lobbyists and activists convinced the politicians that it would 'save the world'...
b) because the science has been so corrupted that official policy cannot recognise any other path...
c) because as part of this process the politicians planned to apply huge taxes on conventional energy supplies, and their figures now rely on that income. So they can't possibly recognise that there is no need to do this.....
It would appear that windmills are an exquisitely expensive solution to a non–existent problem.
@Scottie
It would appear that windmills are an exquisitely expensive solution to a non–existent problem.
Um..no, they solve a lot of problems. Just not the CO2 one which, as you have said, does not exist.
1 - they justify the work of umpteen activists, journalists, 'green' manufacturers and civil servants
2 - they justify a punitive tax regime
3 - they enable Britain to say 'We are doing something' to the rest of the world
4 ....
I would recomment The Wind Farm Scam by John Etherington: he lays it all bare.
This debate is no longer about engineering or energy. It's about corruption by the political classes and their 'renewables' industrial-academic complex (to echo Eisenhower's closing presidential speech).
African kloeptocracies manage to siphon off national wealth by direct theft; in the West they accomplish the same by setting up businesses and passing laws in full view of the gullible public. Where are we going to find a group of politicians with the integrity to challenge this massive raid on the public purse under an enviro-mentalist smokescreen?
Nigel Lawson is a rare example of the Right Stuff. I pray that he gathers around him a group of Young Turks who will seize this political opportunity and denounce the renewables conspiracy.
@Dodgy Geezer
.... and they enable wet behind the ears, brain-dead politicians to pride themselves that they are saving the world when all they are doing is facilitating its return to the Stone Age.
Thanks to Phillip Bratby for quoting Dr Etherington’s question and the ghastly government reply.
No doubt Etherington’s question, very technically phrased, is the crucial test of whether any CO2 is being saved. The government boffins’ answer is that they can’t say because they haven’t modelled what would have happened in the absence of wind power.
The obvious follow-up is why did the government promote wind power, subsidise it, and set targets for it, if they could not be sure it would save any emissions, and still don’t know now if it is saving them. Saving emissions is the only potential advantage of wind power. In every other respect it is clearly inferior to traditional means of electricity generation. It takes lots of space, needs new transmission infrastructure, requires heavy maintenance, makes a lot of noise, is ugly, and most of all generates the lowest quality, most unpredictable power of any method.
While Etherington clearly wanted to ask a valid technical question that left no room for evasion, he might have more clearly made his point if he had just asked if the Government knew whether, counting all relevant factors, it was saving any emissions with wind power, and if so how much. He may have got the same non-answer, but this would have made it even more obvious just what a frivolous farce wind has been.
Off-topic but relevant..
Politics. Comes from the words 'poly', meaning many; and 'tics', small blood-sucking insects...
Well - I liked it...
Gareth/Michel
The faceplate capacity is presumably used to 'big up' the windmills. I don't imagine they would get very far if they had to quote real-world outputs!
Head over to Tim Worstell's place. He's talking about it.
http://timworstall.com/2012/08/18/calling-william-connelly/#comments
His Highness, The Emperor of Wikipedia, William Connolley, has announced that "Since this is from bishophill its no great surprise that its wrong."
Heh.
Should read: "Since this is from an engineer's submission to Parliament its no great surprise that its wrong."
Like the National Lottery, windmills are immensely successful as a mechanism for transferring wealth from the poor to the rich.
Except that, unlike the Lottery, the poor taxpayer has absolutely no choice whether to take part or not.
@Dodgy Geezer, cerberus
An influential figure in Cameron's inner-clique is Oliver Letwin, who wrote a whole page of sanctimonious claptrap in the Telegraph early last year on why it was 'absolutely right' that Britain take the 'moral lead' on overseas aid and climate change. The hideous incompetence of Labour has been replaced by a government of clueless prats who haven't grown out of sixth-form politics.
I think I'm convinced that while the truth may be higher or lower, this is the wrong approach both in the arithmetic and in conception. It confuses capacity factor with variability which is different and depends on many other details.
First, in the arithmetic. Suppose,for whatever reason, we wanted to add 1GW of wind capacity to the grid. If we expected a capacity factor of 25% we would build 4GW of faceplate capacity. If we run this system for 1 hour then on average we will contribute 1GWh electricity to the grid.
But, claims Bowie, to make that usable you will need 75% backup from OCGT. That is, you will have to generate another 0.75GWh at 600 tonnes / GWh. That gives an emission rate of 600 / 1.75 = 343 tonnes / GWh. By Bowie's figures the emissions from OCGT are 400 tonnes / GWh so there would be a (small) saving in emissions.
Second, and far more importantly, it is conceptually confused. The amount of backup, and the amount that must be met by OCGT, is not defined by the capacity factor.
Let me give some examples. The proportion of backup needed depends on the absolute amount of capacity. If you build 4MW of turbines and connect them to the grid with a capacity factor of 25% then the grid will not need 3MW of additional backup. The fluctuations can be absorbed in existing flexibility. 4GW nameplate that fed in an average of 1 GW may have a more noticable effect relative to fluctuations in demand, but the proportion of back up needed would surely be less than 40GW of capacity feeding in 10 GW average power.
But even presuming that demand is otherwise flat, capacity factor is still just not the same thing as variability.
This is illustrated by the argument about whether the need for back up can be mitigated by averaging over a larger area. Perhaps there are times that the whole of Europe is becalmed. That would imply that we need back up on hand to meet all of what we rely on for wind. But if you can see that connecting together larger grids makes times at which there is no wind anywhere (and times at which every turbine is simultaneously producing at peak) less common then you will see that the amount of back up that actually has to be run, and associated emissions, will be reduced. This is true even if the capacity factor remains identical.
The capacity factor also doesn't say how much demand can be met by OCGT vs. CCGT. Some sources of energy are more predictable than wind e.g. tidal. Solar, has some whether fluctuations, but clear a daily cycle. (Of course there is also the maintenance cycle for nuclear, coal, gas, etc which reduces capacity factor there below 100%. With good engineering this should be planned down time, but there are always exceptions.) When there is clear possibility of planning ahead, and long periods of down time then backup can be easily met with efficient CCGT. It is the spikiness, suddeness and unpredictability of wind that mandate the balance of OCGT vs CCGT backup. Those numbers are not contained in the capacity factor.
For example, if we consider the possibility of technological progress it may be that smoothing through larger grids, wind forecasting and storage on time scales of minutes to hours allow more backup to shift from OCGT to CCGT (how long does it take a CCGT to warm up?) *even if the capacity factor does not improve*.
In summary, it seems to me that the amount and type of back up required is a complex question that cannot be answered (even approximately) by looking at capacity factor. That's conceptually wrong.
A comment on Worstall's blog from "turnedoutnice":
'Gareth and Connolley are wrong as one has come to expect from people apparently educated in different physics than reality**.
If you design windmills with a given ‘nameplate capacity’ and connect to a synchronous grid, you must expect at times to have a high proportion of this. To imagine you can have 4 times 25% to give 100% is yet another example of the childlike understanding one has come to expect from these blinkered zealots.
The Danes found this in 2004 when they learnt that by forcing other plant to cycle to follow changing wind power, the system produced more CO2 that without the windmills >~10% of instantaneous demand. They now dump excess wind energy to hydro.
Reportedly DECC’s CSO, MacKay, warned windmills can only save CO2 if we install pump storage, flooding most of the Lake District and much of Scotland, pumped by nuclear power [you can’t pump with wind surges]. Apparently Davey has placed hands over his ears saying Nah! Nah! Nah!, expected from a PPE graduate.
**The key mistake [of 6] is to believe ‘back radiation’ can be measured by ‘pyrgeometers’. Any competent scientist realises these measure a temperature radiation field which can do no work. You prove it by having two, back to back, in which case the net signal in zero temperature gradient is zero: http://www.kippzonen.com/?product/16132/CGR+3.aspx
The IPCC ‘Energy Budget’ is a fabrication based on faulty experiments, climate science has the forecasting ability of the entrails of a dead skunk and the people are trained in false physics. Connolley is a very good example of the kind of kook who inhabits this World!.'
JK:
I would have thought it was rather simpler than that.
Suppose that our current fleet of wind turbines contributes about 3% to the UK demand - say 1,000 MW to an to an average demand of 35,000 MW. Government policy says that "renewables" (i.e. wind) must contribute 30% (i.e. 10,000 MW) by 2020. (It's utterly impossible, of course, but that's a separate matter.) As there will be periods when wind produces no power, a back up facility producing a maximum of 10,000 MW will be required. Wind turbine faceplate capacity is essentially irrelevant.
QED.
Or am I missing something?
@DaveS
On the subject of the Cameroons words simply fail me. Letwin, the theorist hasn't even got as far as grasping simple concepts such as public goods or free riders. We all accept that politicians are a disaster in the normal run of things but to achieve the staggering levels of incompetence this lot have managed takes idiocy of a more exalted kind. If they had been selected at great length for pig headed stupidity it couldn't have been done better.
A few weeks ago there was an article in the DT colour magazine about a wretched offshore wind farm. If I remember rightly the Cameroon in question stated that abundant energy from wind was there for the taking, thousands of times the country's needs. At that point I couldn't bear to read any further.
Robin,
I think it's true that a back up supply of 100% of the wind contribution has to be on hand.
But the question of how much back up is required is a different one.
To go with the 30% example, suppose we want 10GW over one month of thirty days.
Wind produces an average of 3GW, so at a capacity factor of 25% we would need the same nameplate capacity of 12GW in each case.
Case 1: For 9 days of the month wind produces 10GW and for 21 days it produces nothing.
Needed backup = peak wind output = 10GW
Backup energy produced (proportional to CO2 emissions?) = 210 GW-days
Additional 70% of non-wind energy on grid already accounted for by backup.
Case 2: Every other day wind produces 6GW and on the off days it produces nothing.
Needed backup = peak wind output = 6GW
Backup energy produced (proportional to CO2 emissions?) = 90 GW-days
120 GW-days of non-wind energy on grid needed beyond backup.
Case 3: Every day wind produces 3GW, except for brief spikes when it produces nothing.
Needed backup = peak wind output = 3GW
Backup energy produced (proportional to CO2 emissions?) = brief spikes to avoid black outs.
210 GW-days of non-wind energy on grid needed beyond backup.
In addition we could say that while case 1 requires most back up and case 3 least, the back up has to work fastest in case 3. You could argue that case 1 just requires a quick transition when the wind stops blowing (e.g. from pumped hydro) and then for the rest of the month efficient CCGT could be used. In case 2 the ups and downs are more common, so maybe this would be a situation where more OCGT would be necessary.
When you consider that cases 1, 2, and 3 also generate different amounts of total energy and remember that there is a re
The other point that there is not really a strong logical separation between 'back up' and 'non-wind energy on grid needed beyond backup' . I don't believe that power stations come with labels on them saying which is which. This shows that the question of CO2 emissions from back up will also depend on the rest of the mix, not just what is specifically built as backup.
My cases are just abstract possibilities. All they are intended to illustrate is that it is hard to settle the question with the information available. It maybe that we just need a few more numbers related to variability to make a back of the envelope estimate, or it may be a rather more difficult calculation. But certainly at least some more empirical imput is needed.
Edit - senior moment wrong thread, I will get my coat!
@ the Bishop: "Now, where does the alternative view - the one proclaimed by Grantham Institute man Robert Gross - come from?"
Well, out of his hat, of course.
What is the true cost of wind energy?
The answer is pure QI “Nobody Knows”
The “elephant in the room” or the “elephant in the turbine” is their yet unknown life cycle O & M costs. Many can guess, many can predict but large rotating equipment especially in hostile offshore environments ages quickly and as we all know the cost of maintaining the elderly is escalating.
There is a distinct possibility that towards the end of the life cycle the maintenance costs of units could become prohibitive, especially offshore.
http://www.stle.org/assets/news/document/Cover_Story_06-10.pdf
"Wind turbine gearboxes have yet to achieve their original design life goals of 20 years."
“Most turbines require significant repairs and even complete overhauls in the 5-7 year range.”
Climate extremists at the end of the day are delusional wasteful twits.
The sooner their ideas are run off to the the rubbish heap the better.
Regretfully, lurjer, the 1945 plan to Unite Nations, end national boundaries, promote misinformation, and control people through electronic surveillance has very deep roots and will not "run off to the rubbish heap."
See the UN's Agenda 21: http://www.un.org/esa/dsd/agenda21/
The Global Climate Scam: http://www.youtube.com/watch?v=m3VIFmZpFco
DaveS, Dodgy Geezer, cerberus:
Here's what Oliver Letwin said:
Perhaps he sees it as the White Man's burden.Dodgy Geezer: Aug 18, 2012 at 10:14 AM
The key point for Falkland Islands wind power is that provision of diesel fuel is very difficult. It has to be expensively shipped in ...
Yes, but I was looking for actual figures for CO2 savings, and these are hard to come by.
As it happens they've cut their fuel consumption by 52%. Partly by more efficient use of the wind power, partly by doubling the number of turbines, and above all, by recovering the waste heat from the diesel generators as hot water, and circulating this in Stanley for heating the houses. This practice is used in the Baltic countries, Sweden and Denmark esp. Obviously it wouldn't work in Bahrein or Tahiti.
I have always felt that wind turbines are best on cold, wind-swept isolated islands, along with those who put turbines all over the countryside.
michel: Aug 18, 2012 at 8:46 AM
JK: Aug 18, 2012 at 5:45 PM
There is considerable merit in what you say about using only capacity, but the gross capacity is the publicized figure leading to many ignorant people e.g. politicians to assume that is the amount delivered. Even Gareth seems not to realize that the authorities are expecting at least 50% of the 30GW capacity as output.
The figure of 25% is an average. At times (rare) a wind farm will output near maximum capacity, and at other times zero. Changes can be quite rapid. This is usually covered by hydroelectricity which can change output rapidly, but with increased amounts of wind the grid has to cope with both situations, and coal, CCGT and nuclear are too slow to react. CCGT is perhaps the best (least worst) option in that it can sometimes be run as an OCGT, with loss of efficiency, higher cost of electricity and CO2 emissions. It is cheaper to cover the changes in output of the wind farms with OCGT.
JK, the OCGT doesn’t have to run only when wind is not delivering, standby mode would require some of the OCGT to be turning over at synchronous speed, so they can be ramped up quickly. Starting from a dead stop is too slow, and the grid would go down. This running with minimal output generates more CO2 per MWh than the 600kg figure given. This amount of CO2 has to be added to the bill.
At present, wind power is contributing 182 MW to a UK demand of 30,040 MW - i.e. 0.6%. The dreaded coal is contributing 11,100 MW (37.9%).
This little app is very nice: http://www.ideasproject.info/software.php
It shows data from wind, gas, coal, nuclear and water, comparing their CO2 impact.
This fraud extends to other technologies which are assumed to save CO2 but actually just shift the emissions elsewhere. Joseph Dunn and Dominic Tobin report in the Sunday Times today about another example: "THE HOLES IN OUR ELECTRIC DREAM"
"Ozzie Zehner, a visiting professor at the University of California, has made waves by arguing that electric cars are not green, not clean and do more harm than good. The multi-million pound subsidies being given to encourage their adoption are, therefore, a colossal waste of money."
Zehner has written a new book "Green Illusions" which brings the following to the readers attention:
"...hybrids and electric cars are no better than gasoline vehicles, a conclusion backed by a National Academy of Sciences report."
Zehner points out that the higher cost of electric cars reflects the greater quantities of fossil fuels used to build them. He argued that electric cars do not eliminate the negative side effects of vehicular travel. They merely shift the problems elsewhere.
PR Newswire (http://s.tt/1e2GL)
Academics and policymakers have let us down again. Most electric vehicle studies compare traditional gasoline fuel to electric car charging, which relies primarily on coal, natural gas and nuclear power. However, fueling activities represent only a portion of a car's total environmental impact. Zehner points out that the larger impact comes from manufacturing the car . The added copper, aluminum, rare earth metals and other materials necessary for electric car production offset any benefit achieved during the entire charging lifecycle.
Tail pipe emission tagets are used by the European commission to artificially incentivise the building of electric cars. In most other products Life Cycle Emissions are used - this is the real carbon footprint. If the commission switched to LCA targets then no EVs would get built.
Niels: yes, a nice app. But, although it shows the overall CO2 impact, its real merit is that it shows the percentage contribution each of these power sources is currently making to the UK demand - e.g. wind now at 0.8%
@Niels :
@Robin is correct - If you use that app for calculating CO2 you will get a wrong answer.
Wind has a CO2 value of zero g CO2e/kWh where clearly the arguments here show that is not the case. Even nuclear is listed as 16g CO2e/kWh but the average value is more like 66g - nuke emissions can be as much as 288 g CO2e/kWh (Sovacool, B. Energy Policy 36, 2950–2963 (2008). http://bit.ly/9MnEjw )
The use of simplistic measurements which are then easy to communicate is one reason why politicians get away with promoting biased policy.
Reliance on "Apps", tail pipe targets, DECC spreadsheets and other simplistic tosh is contributing to our energy nightmare.
Gas is the only reliable source of clean, cheap power. Gas stations can even use renewable gas if they can find any. So why are we guffing around when we could be putting all our energy ;-) into securing gas supplies?
Supreme logic fail here.
If the expected capacity of the wind plant is 25% of the rated capacity, the dispatching agency is not going to plan for 100% output for capacity purposes and have backup to cover that 100% output.
When the output does go above the average, it is considered an opportunity to shut off more expensive generation sources.
They will only plan on relying on the wind power for a sub-percentage of the 25% for capacity purposes. And the backup amount required for the wind component alone may still be within range of the backup needed to cover other contingencies, such as a large nuclear or coal plant going offline. Thus, no additional backup capacity may be required.
The amount of backup required for a given territory is highly situational, depending on the power supply resources available to the region being dispatched, and what failure mode is the largest worse case scenario - for example, a transmission line failing, or a nuclear power plant shutting down unexpectedly.
As to spinning reserve for regulating voltage, that is already required regardless of the source of power to handle fluctuations in demand and the possibility that any generating unit may trip offline without warning. Wind power does require a bit more spinning reserve than conventional generation due to its' natural minute by minute fluctuations, but it is a very small percentage of the wind power output.
Current forecasting techniques provide accurate enough hour ahead predictions of wind speed, so there is plenty of time to bring other resources up to speed as wind is predicted to drop during daily operations.
Tying together spatially diverse wind farms significantly reduces the variability of the sum of the wind energy output. Continent-wide connections would allow for relying on wind for an increased amount of base capacity.
I've got a couple of questions.
1. Most of the discussion above seems to assume an all or nothing scenario. Surely that fact the wind is variable and will supply a fraction, from zero to one, of it's rated capacity leads to greater inefficiencies?
2. My understanding is that in addition to the need to power up the backup units when wind drops there is also a problem of powering down the generators when the wind starts blowing. Is that the case?
Merci Amigo: look at the real data.for real systems. Fred Udo shows that there is little if any CO2 saving in the Irish grid using the real fuels efficiency data.
Adding windmills up to 10% average demand saves 4% of the CO2 without costing the CO2 in the windmills. Push more than 10% wid power in and there is no more CO2 saving. This was for a grid with some hydro power. A grid like ours would be worse off. Smart metering could help quite a bit but operating experience shows that the only real saving in most grids is the switch from coal to methane, not the windmills.
The intermittent / erratic nature of wind power induces instability in the grid system and requires the provision - somewhere - of alternative or standby generation capacity. As a result the wind farm operators get the “cream” of high “renewables” feed-in tariffs, whilst society at large is expected to pick up the tab for the overall inefficiencies and higher costs that result.
Why not advocate a change in approach, via the “sceptic” community, to help highlight the current parasitic nature of wind energy schemes?
Why not actively encourage developers to build more wind farms? But only with the proviso that the planning and DECC consents for the projects should require - at no cost to the taxpayer - the parallel installation and operation of new, dedicated standby capacity, equivalent to 100% of nameplate capacity as an integral part of - and hypothecated to - the project. In this way a wind turbine project can make the same commitment to continuous supply as required from fossil fuel / nuclear stations, make some meaningful contribution to base load and not get a free ride. And, should any wind schemes still go ahead under this proviso, at least the gas turbines can continue in operation when the wind turbines are, inevitably, “kicked into touch”.
It would be interesting to see prospective wind farm developers attempting to justify why they shouldn’t have to fund the availability of the gas turbine plants on which their projects will ultimately depend.
Merci Amigo is correct that the dispatching agency will not plan on the full 25% of rating plate, I think the actual figure is around 10%. To put that another way, when planning forward the wind generation capacity has to be regarded as almost non-existent, and the requirement is planned to be filled with non wind. (i.e. the wind powered generation may as well not be there). [Remember here that you're not looking at the long term averages, but planning on what needs to keep the lights on on a given day within the next week, say]. If the wind does deign to blow, then you do in a sense have 'extra' power, but the uncertainty is sort of +/-1GW or even more (looking at the neta site over a week shows that even over 24hrs the difference between forecast and actual can be nearly 2GW on occasion). This power then has to displace the planned capacity, and the fast responding plant then has to be in load following mode, running up and down to balance the system which introduces the inefficiencies and extra fuel use. As the wind capacity grows the problem does too. Sure, in a large enough, well planned system this can be accomodated, but once the wind capacity is larger than (say) the normal largest generator in the system the problem becomes much more difficult to handle. As Scottie might say, the UK grid canna take much more of this Captain.
In Germany, they have a large interconnected system, but even there the wind is becoming a problem, particularly since they also have a large PV load to deal with which can suddenly feed large amounts back into the system over a myriad of small connections designed to deliver to homes, not take from them.
Merci Amigo:
Some of what you say is true – especially (I believe) your observation that, if “the expected capacity of the wind plant is 25% of the rated capacity, the dispatching agency is not going to plan for 100% output for capacity purposes and have backup to cover that 100% output.” But I’m dubious about your claim that if wind output goes above average “it is considered an opportunity to shut off more expensive generation sources”. Have you any evidence to support that?
But that’s not the main issue. There’s a difference between the risk of a nuclear or coal plant failing and of wind producing no power – i.e. when wind speed is too low or too high. When did a large UK nuclear or coal plant last go off line? In contrast, surprisingly often (such as now), wind turbines throughout the UK – onshore and offshore – produce essentially no power. See this Stuart Young Consulting report.
That doesn’t matter now when wind power is contributing on average only about 3% of our needs; the mechanisms you outline can easily cope. But the Coalition plans** that, within five years, about 20% of our power is to come from “renewables” (i.e. wind). (See Ministerial statement here – ninth paragraph.) A total failure of 20% of our energy needs would be considerably more serious than even a large nuclear plant going off line: all our nuclear plants would have to fail at the same time for there to be a 20% shortfall. Yet you indicate that the backup required would be “within the range needed to cover other contingencies”. I don’t think that’s the case – or do you have evidence to the contrary? And, unless the necessary backup was available (and I know of no plans for this), such a failure would mean power outages. And power outages can be exceptionally serious. I think few people appreciate, for example, the fragility of a modern city: in periods of extreme heat or cold, it’s electricity that prevents disaster. And, throughout the UK (and this can extends to much of Europe), the wind typically doesn’t blow in periods of extreme heat or cold. See this.
So where’s the “supreme logic fail?
** The fact that this plan is unachievable is another matter.
The 20% renewables' figure is for all energy sources including heating. Blair did not realise this when he agreed it. The real figure for electricity is 32%..
This is not possible by wind because the UK grid can't cope with 20% let alone higher wind and at that penetration there is no CO2 saving. The only option is to expand biomass and waste-to-energy, which is what appears to be being developed.