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National Grid report challenges wind energy critics

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.

(...)

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.

(...)

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.

Go check the tables at the link.

Wind power

by Jerome a Paris (etg@eurotrib.com) on Wed Jun 26th, 2013 at 05:23:21 PM EST
Wind critic modus operandi:

  1. - Wind is intermittent, putting a strain on the balancing capacity of peaker plants!
    - But wind is predictable, most of the variability can be balanced on a scheduled basis. =>
  2. - Wind needs a matching reserve capacity of mid-merit fossil fuel plants which spew CO2!
    - But so does nuclear, and wind+solar require less and the balancing plants will have low capacity factors and thus won't spew much CO2. =>
  3. - Idle (reserve) plants are a waste and make the system more expensive!
    - But it is the nature of mid-merit and peaker plants to have low utilisation, because their costs are dominated by fuel. =>
  4. - Low utilisation and low wholesale prices due to renewables eat at the profits of balancing plant operators and make them close shop!
    - But maybe that means those plants aren't needed, after all? And if the situation becomes critical, you can always look beyond market solutions, from forcing operators to close the dirtiest baseload plants (resulting in higher utilisation of mid-merit plants and higher wholesale prices) through bonuses for reserve plant operation to tax-financed public operation of reserve capacity. =>
  5. - The grid can't take large back-and-forth flows due to intermittency!
    - But renewables with improved technology are spreading in regions where they have been rare previously, new grid capacity is being added even if slowly, and the operation of the existing grid is being made more efficient. =>
  6. ?


*Lunatic*, n.
One whose delusions are out of fashion.
by DoDo on Thu Jun 27th, 2013 at 04:00:39 AM EST
[ Parent ]
4 - Low utilisation and low wholesale prices due to renewables eat at the profits of balancing plant operators and make them close shop!

Only in times of high wind. Allow the plants to charge more when renewables are low... smart grid. The market does work if you let it

  1. Wind turbine syndrome

  2. Fuck you greenies
by mustakissa on Thu Jun 27th, 2013 at 05:55:36 AM EST
[ Parent ]
6. Luckily, there is an army of electrical engineers scrambling around in the background to keep the grid on the air as all the various sources and loads change. Not like the good old days, where all you had to do was keep the synchronous clock more or less on time.

If gold hand lines up with black hand, yer power plant is good.

http://www.my-time-machines.net/warren_master_clock.htm

by asdf on Thu Jun 27th, 2013 at 01:36:18 PM EST
[ Parent ]
Here two studies from the Finnish State Technical Research Centre (VTT):

Wind power forecasting accuracy and uncertainty in Finland

Wind and load variability in the Nordic countries

(h/t Tuomas Helin)

Basically similar conclusions.

by mustakissa on Thu Jun 27th, 2013 at 06:03:09 AM EST
[ Parent ]
The second study is of further interest due to the analysis of correlation in load variability between the Nordic countries, based on 2009-2011 data. They find 0.7 correlation between Denmark and Sweden but weak correlation in other pairings. Looking at it another way, for single countries, there are periods when actual power from all wind turbines is 2-5% of the total power (mostly in the summer), but for the entire region, the minimum is 14%. As for over-supply: with their scenario for wind power expansion in the region to an annual penetration of 30%, while production in Denmark could peak at 160% of domestic consumption, for the entire region, it's 110%.

*Lunatic*, n.
One whose delusions are out of fashion.
by DoDo on Thu Jun 27th, 2013 at 06:30:54 AM EST
[ Parent ]
for the entire region, the minimum is 14%

I misread: 14% is the minimum during the ten highest daily peak loads. There were sub-5% events for the entire region, though their number and length would reduce significantly with increased capacity in Finland. Also, this analysis excludes Norway.

*Lunatic*, n.
One whose delusions are out of fashion.

by DoDo on Thu Jun 27th, 2013 at 06:49:17 AM EST
[ Parent ]

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