Surprise, surprise: Wind turbines do lower carbon emissions

Counter-intuitive thinking is counter-intuitive for a reason.

Climate sceptics have long made the counter-intuitive claim that wind turbines don't actually reduce carbon emissions, but data analysed by the Guardian's environment blog suggests that as well as being counter-intuitive, it's just plain false.

The claim the Guardian's Chris Goodall and Mark Lynas investigated relies on the fact that wind power fluctuates with the weather. As a result, when the windspeed drops, gas power stations have to be spun up to provide electricity instead. It has to be gas, because other low-carbon sources of energy either have the same fluctuations as wind, or, like nuclear power, essentially can't be turned off.

The sceptics argue that the need to rapidly turn on the gas generators means that a type of power station known as a "gas-fired open cycle turbine" (OCGT) has to be used. Their key point is that these turbines, which are capable of being put into use extremely quickly, are less efficient than another type of gas generator, a "combined cycle gas turbine" (CCGT). The need to pick up the slack left by wind power, they say, means that so many of these inefficient turbines are used that carbon emissions actually go up compared to the scenario where all the electricity is generated with the more efficient CCGT type.

The Guardian's blog contains a lot of stats taken straight from the National Grid, all of which confirm the intuitive beliefs: wind power replaces fossil fuels. But for the specific claim that it still results in higher carbon emissions, the operative paragraph is the following:

Their arguments are not borne out by current statistics, however. If the sceptics were right, the recent windy conditions would have seen considerable use of less-efficient OCGT as wind input to the grid ramped up and down. In actual fact, during the entire June-September period, OCGTs and equally dirty oil-fired stations produced less than one hundredth of one percent of all UK electricity. In total they operated for a grand total of just nine half hour periods in the first 19 days of the month – and these periods had nothing to do with changing windspeeds.

In other words, the mechanism the sceptics suggested might be at work isn't. The authors go into greater detail about why that is, as well. In essence, it comes down to the fact that wind power isn't actually all that unpredictable. It comes and goes, but we usually have a good few hours warning about when it's going to die down; and it's spread throughout the country, allowing even more flattening of the peaks and troughs in supply.

The bigger reason for having to suddenly spin up big generators isn't sudden drops in supply, but sudden peaks in demand. Take, for example, a World Cup match, where England have made it through to sudden death penalties. The National Grid know there will be a spike in power consumption the minute the match ends, as people get up to put the kettle on – but they can't know when that spike will be until mere seconds before it actually happens. That sort of load will always be problematic to supply with renewables – but it's not much less problematic to supply with fossil fuel either.

Wind turbines. Photograph: Getty Images

Alex Hern is a technology reporter for the Guardian. He was formerly staff writer at the New Statesman. You should follow Alex on Twitter.

Photo: Getty
Show Hide image

Who will win in Stoke-on-Trent?

Labour are the favourites, but they could fall victim to a shock in the Midlands constituency.  

The resignation of Tristram Hunt as MP for Stoke-on-Central has triggered a by-election in the safe Labour seat of Stoke on Trent Central. That had Westminster speculating about the possibility of a victory for Ukip, which only intensified once Paul Nuttall, the party’s leader, was installed as the candidate.

If Nuttall’s message that the Labour Party has lost touch with its small-town and post-industrial heartlands is going to pay dividends at the ballot box, there can hardly be a better set of circumstances than this: the sitting MP has quit to take up a well-paid job in London, and although  the overwhelming majority of Labour MPs voted to block Brexit, the well-advertised divisions in that party over the vote should help Ukip.

But Labour started with a solid lead – it is always more useful to talk about percentages, not raw vote totals – of 16 points in 2015, with the two parties of the right effectively tied in second and third place. Just 33 votes separated Ukip in second from the third-placed Conservatives.

There was a possible – but narrow – path to victory for Ukip that involved swallowing up the Conservative vote, while Labour shed votes in three directions: to the Liberal Democrats, to Ukip, and to abstention.

But as I wrote at the start of the contest, Ukip were, in my view, overwritten in their chances of winning the seat. We talk a lot about Labour’s problem appealing to “aspirational” voters in Westminster, but less covered, and equally important, is Ukip’s aspiration problem.

For some people, a vote for Ukip is effectively a declaration that you live in a dump. You can have an interesting debate about whether it was particularly sympathetic of Ken Clarke to brand that party’s voters as “elderly male people who have had disappointing lives”, but that view is not just confined to pro-European Conservatives. A great number of people, in Stoke and elsewhere, who are sympathetic to Ukip’s positions on immigration, international development and the European Union also think that voting Ukip is for losers.

That always made making inroads into the Conservative vote harder than it looks. At the risk of looking very, very foolish in six days time, I found it difficult to imagine why Tory voters in Hanley would take the risk of voting Ukip. As I wrote when Nuttall announced his candidacy, the Conservatives were, in my view, a bigger threat to Labour than Ukip.

Under Theresa May, almost every move the party has made has been designed around making inroads into the Ukip vote and that part of the Labour vote that is sympathetic to Ukip. If the polls are to be believed, she’s succeeding nationally, though even on current polling, the Conservatives wouldn’t have enough to take Stoke on Trent Central.

Now Theresa May has made a visit to the constituency. Well, seeing as the government has a comfortable majority in the House of Commons, it’s not as if the Prime Minister needs to find time to visit the seat, particularly when there is another, easier battle down the road in the shape of the West Midlands mayoral election.

But one thing is certain: the Conservatives wouldn’t be sending May down if they thought that they were going to do worse than they did in 2015.

Parties can be wrong of course. The Conservatives knew that they had found a vulnerable spot in the last election as far as a Labour deal with the SNP was concerned. They thought that vulnerable spot was worth 15 to 20 seats. They gained 27 from the Liberal Democrats and a further eight from Labour.  Labour knew they would underperform public expectations and thought they’d end up with around 260 to 280 seats. They ended up with 232.

Nevertheless, Theresa May wouldn’t be coming down to Stoke if CCHQ thought that four days later, her party was going to finish fourth. And if the Conservatives don’t collapse, anyone betting on Ukip is liable to lose their shirt. 

Stephen Bush is special correspondent at the New Statesman. His daily briefing, Morning Call, provides a quick and essential guide to British politics.