Environment

National Grid report challenges wind energy critics

National Grid report challenge...
Sheringham Shoal Offshore Wind Farm, UK (Photo: Harald Pettersen/Statoil)
Sheringham Shoal Offshore Wind Farm, UK (Photo: Harald Pettersen/Statoil)
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Sheringham Shoal Offshore Wind Farm, UK (Photo: Harald Pettersen/Statoil)
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Sheringham Shoal Offshore Wind Farm, UK (Photo: Harald Pettersen/Statoil)
(Table: National Grid)
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(Table: National Grid)
(Table: National Grid)
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(Table: National Grid)
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Squirreled away beneath a recent Telegraph report on the subtleties of badger-culling in the UK was this intriguing morsel of wind energy news, which would seem to challenge the idea that intermittent energy sources such as wind play havoc with grid management. For the 23,700 gigawatt-hours of electrical energy generated by wind in the UK between April 2011 and September 2012, only 22 GWh of electrical energy from fossil fuels "was needed to fill the gaps when the wind didn't blow," it reports. Gizmag contacted the UK National Grid to find out the details.

The Telegraph's figures come from National Grid Head of Energy Strategy and Policy, Richard Smith, speaking at the Hay Festival between May 23 and Jun 2. Gizmag has learned that he was drawing from a National Grid document sent to the Scottish Parliament in response to its own report of Nov 23 2012, entitled Report on the achievability of the Scottish Government's renewable energy targets.

(Table: National Grid)
(Table: National Grid)

Table 1 of the National Grid's document states that, according to its figures, wind farms generated 23,707 GWh of electricity over the 18 months in question.

(Table: National Grid)
(Table: National Grid)

Meanwhile, Table 2 of the report shows the energy provided by the National Grid's Short Term Operating Reserve, and how much of that was due to wind energy output being lower than forecast. Of the 246 GWh provided by the Reserve for the same period, 22 GWh are thought to be due to the wind not blowing as forecast.

In other words, for every 1,000 GWh of wind energy generated in that 18-month period, less than 1 GWh was required to meet shortfalls due to the wind not blowing as expected. "As expected" may be the crucial words missing from the Telegraph's summary. What about the energy required when the wind isn't blowing, when you know it isn't going to blow, you may well ask? But, similar to the classic falling tree scenario, is a GWh of energy truly "lost" if you weren't expecting to generate it in the first place? At the very least, the National Grid's figures would seem to challenge the notion that wind energy throws the grid into significant disarray.

Further, because of the carbon implications of these figures, the data simultaneously challenge another knock-on concern about wind energy – one raised in paragraph 121 of the Scottish Parliament's report. It specifically calls on the National Grid and the UK Government to clarify "whether 'reducing the carbon intensity' of the grid takes account of electricity which is generated from thermal [i.e. fossil fuel] plant but, due to despatch decisions, does not make it as far as the grid, whether this is expected to be a continuing issue and, if so, for how long."

In other words, the Scottish Parliament's specific question is whether wind energy can actually waste energy. If, say, Walney 1 suddenly spins into action, is this reducing the efficiency of fossil fuel power stations because they've produced energy which is suddenly surplus to requirements? Could such inefficiencies wholly or partly wipe out carbon emission reductions made by having wind turbines in the first place?

Though the reductions in carbon emissions due to wind energy generation (and increases due to the wind not blowing as forecast) are only estimated in the National Grid report, the figures are striking, if not unexpected given what we've already learned. Over the 18-month period, the 23,707 GWh of wind energy generated resulted in an estimated reduction in CO2 emissions of 10.9 million tonnes. Meanwhile the "intermittency impact" of the wind not blowing as expected was an additional 8,800 tonnes of CO2. "The report concludes that this effect causes only a small effect on the carbon intensity of thermal plant generation which is less than 1 percent of the benefit of carbon reductions from wind farms," it says, somewhat conservatively. The National Grid's own figures suggest that the effect on carbon emissions of wind intermittency is actually less than a tenth of a percent of the overall benefit of wind power.

The reports in question are available on the Scottish Parliament website: Report on the achievability of the Scottish Government's renewable energy targets (PDF); National Grid evidence (PDF).

Via The Telegraph

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37 comments
Hasham Abbas
The only worthwhile metric of whether or not wind power is worth it is if the cost of energy to the consumer is reducing, without the application of government subsidies.
physics314
One myth dispelled (intermittency trouble), one left to go: namely that renewable energy needs subsidies. The only reason this is presently the case is because of the far larger subsidies to the fossil fuel and nuclear sector. Not only direct subsidies, tax breaks, and subsidized insurance, but a slew of protections for these industries that effectively shield them from paying pollution damages in civil lawsuits, or flat out exempt them from environmental requirements that everyone else is subject to. Not to mention the trillions of $$ that the general public is obliged to pay in military expenditures to keep the oil flowing... Make no mistake: if the playing field were level, there would be zero coal and nuclear, and much less natural gas and oil in the energy business, including transportation. The development of renewable energy sources has been held back decades by the massive subsidies to fossil and nuclear.
Phil Clemow
"The only worthwhile metric of whether or not wind power is worth it is if the cost of energy to the consumer is reducing, without the application of government subsidies." This is rubbish. If it was a tenth of the price to produce our electricity by burning children would that make it the right choice?
ivan4
So they are admitting that wing has generated in 18 months nearly the DAILY demand for electrical energy. For those interested in all the generated electricity in the UK go to http://www.gridwatch.templar.co.uk/ where it is shown in diagrammatic form. @physics314. Would you please give citations for your claims of subsidies to the fossil fuel and nuclear power generators.
BeWalt
@Hasham: I'm all for using that metric. And doing the math correctly. That would mean, every type of energy source should be evaluated including every bit of subsidies and especially every last penny of externalities, to be best of our knowledge. If people who really know their stuff do this (economists for example), renewables don't just come out on top. They VASTLY come out on top. Right now we only enjoy cheap and easy energy because we do not give a dang about what happens in 300 or 400 years. For example, we burn in our cars the very stuff that can be used to make solar cells (polymer type, needs another decade of R&D) ...and for what: to transport our lazy selves. That particular example gets me every time I think about it: We burn oil for a one-time benefit that causes a rat's tail of bad side effects. Then, it's gone, for ever. We keep harping on how great an economy we are running based on that. And once it's gone, we'll surely still be pointing out how expensive it is to make solar cells. Which it will be, because we burned all of a potential raw material for that. What a smart "intelligent" species we are...
Dekarate
Last I looked solar cells are silicon based and oil is largely carbon based. Two different raw materials. But here is a real question. The UK pulled 23,7000 gigawatts of energy out of the wind - did that alter the climate? - the butterfly flaps its wings in China and there is a hurricane in the Atlantic effect. The CO2 argument is crap. The recent highest peak was 400ppm and 525Million years ago it was 7,000ppm (long before man) and the planet was a lot greener.
physics314
@ivan4 I'm not sure if you are really uninformed or deliberately feigning ignorance. In any case, below are a couple of search terms that should lead you to plenty of the evidence of fossil and nuclear subsidies. I will assume that you have, in fact, heard of the Iraq wars, and some of the large oil spills (Exxon, BP...) which have cost the beneficiaries and offenders next to nothing. - Price–Anderson Nuclear Industries Indemnity Act - Halliburton loophole - American Electric Power Company v. Connecticut Other subsidies include the persistent exclusion of coal ash from hazardous waste designation. To say nothing of the glossing over the environmental destruction of mountaintop removal mining and coal ash spills. An excellent article documenting the net-negative effect on GDP of fossil fuel use (and that's excluding the effects of climate change!): Muller et al., American Economic Review (2011) 1649
Justin Chamberlin
The trick to this report is the word "forecast", as in energy from the coal-fired reserves "due to wind output being lower than forecast." All this metric says is that the National Grid people are pretty good forecasters of when and how hard the wind is blowing. It says absolutely nothing, not a word, about power generated by coal/oil/gas/nuclear when the wind isn't blowing. Shame on those not noticing that dirty trick that completely covers up a serious intermittency problem that is and always will be endemic to wind power. Approximately 80% of Denmark's *installed capacity* consists of wind generators, and when those don't turn hard enough to generate electricity for days or weeks at a time (which happens, I used that very data in a school presentation a couple years ago), Denmark has to import electricity from dirty German coal-fired plants. And Denmark is one of the prime places on the planet for wind power resources. Imagine trying to build enough turbines to serve, say, the northeastern U.S. without relying on solar (think about the weather over there), coal, oil/gas, nuclear, or anything else. See this map from the EIA for why that's not a feasible alternative: http://www.eia.gov/energyexplained/images/charts/US_wind_resource_map-large.jpg Unless there is a drastic, revolutionary, and as-of-yet unforeseeable change in wind turbine design or we figure out how to make the wind blow consistently without further energy input, wind power can not be a source of base load power. Ever. It has its uses but it just can't replace coal or nuclear as a base load source. And just because it needs to be said, solar is even worse. There is much more promise for future technology developments to get over the hump but it still has an intermittency problem for most places and where there isn't that problem we would have to destroy thousands of square miles of desert habitat to make it even remotely viable. Thinking long-term, we as a species need to continue to work energy usage - improve efficiency and all that - and figure out how to make helium-3 fusion work, because all the coal, oil, uranium, thorium, and natural gas in the world won't last more than another couple hundred years and there simply isn't enough wind or solar power available to handle the energy needs of a growing, industrializing population.
Rann Xeroxx
I personally think AGW is bunk, that CO2 is a GH gas, just not a very powerful one, that the Earth has been in a warming trend since the last ice age and it has almost nothing to do with CO2. With that said, I think we should get away from burning coal, it's just such a dirty way of producing power. I also agree with the other poster in that we should do away with subsidies to fossil fuel production (as well as "clean" energy) and that what we spend on the military that is directly related to fossil fuel should be equated and tacked onto the fuel cost (same with clean). I think electric cars are the future but the government is abismal at picking winners and should leave that to the private sector. I also think nuclear (fission and fusion) should be research and added to the list of "clean" energy that is domestically produced. This is not a right/left/green/etc issue, just an issue of sustainability, economics, and access.
Craig Jennings
"The CO2 argument is crap. The recent highest peak was 400ppm and 525Million years ago it was 7,000ppm (long before man) and the planet was a lot greener." Don't suppose you know what the sea level was at the same time Dekarate?