Sun writers disagree on windpower
George Osborne and Ed Davey aren’t the only ones to argue over the future of UK energy. An article in The Sun yesterday pits its political columnist Trevor Kavanagh against its environmental editor Ben Jackson. Kavanagh argues it’s time to “scale back support of windfarms” while Jackson “warns a dash for gas would cost us dear”.
It’s an interesting juxtaposition, and it’s welcome to see the Sun giving more than one angle on the debate over energy choices in a single article. It’s unfortunate that Kavanagh’s argument, which is a lengthy rejection of “windmills” – contains some inaccurate facts and figures which Jackson is not really given the space to address.
Kavanagh begins:
“They [windfarms] cost billions but contribute virtually zero reliable energy to the national grid”.
Is this the case? Coincidentally, yesterday also marked the publication of the annual Digest of United Kingdom Statistics (DUKES). According to chapter six on renewable sources of energy, onshore wind power – “as at the end of December 2011, the UK has more than 4.6 gigawatts (GW) of installed capacity, from about 550 wind schemes…” and offshore wind power – “The UK has the world’s largest offshore wind installed capacity, with over 1.85GW installed by June 2012…”.
That’s installed capacity – but how much electricity is actually being generated by UK windfarms? Over the course of 2011, renewables contributed 9.4 per cent of total electricity generation, of which wind was responsible for over half, or 15,750 gigawatt hours (GWh).
“Windmills are so useless that energy firms have to keep conventional power stations ticking over at 60 per cent capacity in case the wind drops – or blows too hard.”
This is a reference to the intermittency of wind power. The wind doesn’t blow steadily, and sometimes doesn’t blow at all. Wind farms need backup power from other fuel sources to ensure demand is met.
To interrogate this statement, we need to look at the ‘load factor’ of the power plants used to back wind up. Load factor measures the average hourly quantity of electricity generated, expressed as a percentage of the average total capacity. So – a load factor of 100 per cent means that a power generator is always running at full tilt. A load factor of 10 per cent means that on average a power station runs at 10 per cent capacity, and so on.
We’re not sure where Kavanagh’s 60% figure comes from, but it appears to be too high. According to DUKES, the average load factor in 2011 for a combined cycle gas turbine – the most likely backup for a wind farm – was 47.8 per cent. But a power plant used to backup a windfarm would have a lower load factor, because it would only be used intermittently. So Kavanagh’s figure of 60% seems very high.
For comparison, average load factors for onshore and offshore wind were 27.3 per cent and 36.8 per cent respectively, according to this DECC article on renewable energy from 2011.
All this is quite technical. In order to get an idea of how big a downside needing backup actually is, you can look at how much it costs consumers. According to the Committee on Climate Change (CCC) renewable energy review, the costs of backup capacity are small. The Director of the CCC, Dr David Kennedy, suggested in an evidence session on the economics of wind power that the cost of intermittency would currently be about 1p per kWh. We’ve gone into the costs of onshore wind in more detail before.
“Despite building 3,800 of these monstrosities, wind power delivers less than one per cent of Britain’s energy needs. Yet the gigantic subsidies for them punish every household in the land. Britain’s drive for renewable energy is costing £15BILLION a year – £670 for each home. Cunningly, the cost is kept off taxpayers’ pay slips and plonked on to energy bills so politicians escape the blame”.
3,800 is about right , according to the British Wind Energy Association. But after that, not so much.
The £15 billion figure appears in a report by anti-wind lobbyists the Renewable Energy Foundation (REF) and covers: “the annual cost of current renewable electricity policies intended to meet the EU Renewables Directive in 2020”. An article in the Spectator supplies the £670 per household conversion.
However, £670 is the total cost per household from now to 2020, not the yearly cost. It is also a cost for all renewables, not just wind power.
In the second part of the article, Ben Jackson responds:
“WE should be aghast at the price of gas. It has risen seven per cent a year for a decade and is now so high that most UK power stations have moved back to burning coal to keep the price down for skint consumers.”
The latest figures from Ofgem show that energy bills continue to rise rapidly and the biggest chunk of this rise is down to wholesale energy costs. The average gas bill was £665 in 2011, rising to £780 in 2012, with the amount of a bill paying for gas wholesale costs rising from £340 in 2011 to £400 in 2012, despite the fact that companies used strategies to even out wholesale prices, such as buying fuels in advance.
Jackson adds
“…the true cost of wind energy is just 2p a day to every UK home, and dropping as technology advances.”
Renewable industry association RenewableUK has used figures from Ofgem to calculate the average cost per household for wind power as “less than 15p a week” – which may be where Jackson is getting the “2p a day” from.
When so much of the UK energy debate is presented as one sided comment, it’s interesting to see The Sun allowing some back and forth, but given the inaccuracies in Kavanagh’s case, you might wonder how valuable the exercise actually is.