Wind Energy’s Contribution to UK Electricity Supply
Claims for wind energy made by the UK Department of Energy and Climate Change (DECC) and the British Wind Energy Association are being put to the test in the present cold period November/December 2010, as they were in January 3-9th 2010 when 2.5 GW of nominal wind capacity delivered a mere 0.1 GW of the UK’s actual peak demand of around 55 GW.
On 2nd December wind delivered between 0.385 GW and 0.610 GW or from 0.7 to 1.2% of the total (54 to 58 GW) delivered by the National Grid to British homes, factories and offices during those 24 hours. It should be noted that wind energy is given preference over all other energy supplies to the Grid as it cannot be switched on and off, so what is recorded as the supply is all that was available at that time.
This means that while coal, gas and nuclear are operating steadily at around 80% of the rated capacity of all their installations which can be connected to the National Grid, at this time of severe cold the Grid-connected wind turbines are operating intermittently in the range 13-24% of their nominal capacity of 2.5 GW. Unlike 3rd-9th January 2010, the pressure over the UK is not particularly high (990-1000 millibars) so there is plenty of wind about, but everyone (besides the present and former ministers in charge of the DECC) knows wind is intermittent on an hour to hour and day-to-day basis.
January by contrast, is usually both the coldest and least windy season of the year owing to the high pressure (1010-1020 millibars) which settles over the British Isles. During that month this year, the wind turbines were stationary for much of the time, sinking at one stage to 25 MW or about 1% of nominal capacity. And this is the system on which the fantasy-led UK government plans to spend between £150 and £200 billion (who knows?) quintupling the number of wind-mills to hopefully supply (on good days) one-third of Britain’s electricity needs. This is in order, so we are told, to meet emission reduction targets foolishly entered into by former prime minister, Tony Blair, and aspiring prime minister, Ed Miliband, when he was Secretary of State for Energy and Climate Change. Meanwhile, after all the dithering by the government, a consortium headed by Scottish and Southern Energy is (thankfully) pressing ahead before obtaining actual planning permission for 3.2 GW of new nuclear capacity at a cost of £10 billion all-in at Hinckley Point in Somerset.
Contribution of Coal
As in January, coal-fired electricity stations are currently steadily delivering, hour after hour about 42% of the nearly 60 GW supplied by the National Grid. On present plans however about half of the nation’s coal-fired electricity, or one-fifth of total electricity supply capacity, is due to be shut down by 2015 on emissions grounds under the EU’s Large Combustion Plant Directive (LCPD) which will also close down so-called non-conforming industrial power stations not connected to the Grid and plant used for other industry purposes such as steel-making.
The most comprehensive published modelling of various supply, emissions and cost scenarios (Bush & MacDonald 2009) shows that only a crash programme of building gas-fired power stations and/or ignoring or postponing the LCPD will avoid huge power cuts at the coldest times of the year in 2015/16. There is now talk of the UK government belatedly waking up to this impending catastrophe and seeking a derogation from the LCPD until 2018. If so they had better hurry up and tell the electricity supply companies, since those companies who decided not to meet the extravagant demands of the LCPD on some or all their coal plant (the “non-conforming plant”) are well into their permitted 20,000 hours of operation from 1st January 2009).
What should the UK do about electricity supply?
In “Maintenance of United Kingdom Electricity Supplies to the year 2020 and proposals for a Secure Energy Strategy (SES)”, Bush and MacDonald compare their nuclear-based SES with the National Grid’s “Going Green” strategy, which was published in June 2009 in response to the DECC’s White Paper in the same month. Basically the SES envisages a steady 2 GW per year of new nuclear electricity generation from 2018 for 25 years with wind energy confined to remote, non-Grid areas of the UK, where it is more effective locally and cheaper to install. The Grid’s strategy relies on an expansion of wind from the current 2.8 GW to around 32 GW nominal (actual about 8 GW) supposedly to be built in the impossibly short time of 10 years from 2010 (i.e. about 3 new turbines every day to 2020) to meet the UK emissions targets foolishly entered into by Ed Miliband on the UK’s behalf.
The Secure Energy Strategy (SES) calls for the closure of coal-burning plant only as new nuclear stations come on line to replace it (from around 2020 onwards). The Grid’s “Going Green” (GG) strategy will, by contrast, require the indefinite retention of every hydrocarbon plant (gas and coal) as “back-up” when, predictably, the wind fails to blow. (Germany has built 20,000 wind turbines and not one hydrocarbon burning plant has been shut down as a result.)
Bush and MacDonald’s models for the SES and GG predict CO2 emissions, as well as cost and output from the various sources (gas, coal, oil, nuclear, wind, hydro, bio-mass, solar) year by year to 2020 and at five year intervals thereafter. Beyond any reasonable doubt the Secure Energy Strategy offers the British people far and away the more cost-efficient, emissions-reducing and above all secure electricity supply for the foreseeable future.
If you would like to check on the current status of the sources of energy used by the National Grid, you can see the Generation By Fuel Type table by clicking on this link and then selecting the table from the listing on the left-hand side of the web page.