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.

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A swimming pool and a bleeding toe put my medical competency in doubt

Doctors are used to contending with Google. Sometimes the search engine wins. 

The brutal heatwave affecting southern Europe this summer has become known among locals as “Lucifer”. Having just returned from Italy, I fully understand the nickname. An early excursion caused the beginnings of sunstroke, so we abandoned plans to explore the cultural heritage of the Amalfi region and strayed no further than five metres from the hotel pool for the rest of the week.

The children were delighted, particularly my 12-year-old stepdaughter, Gracie, who proceeded to spend hours at a time playing in the water. Towelling herself after one long session, she noticed something odd.

“What’s happened there?” she asked, holding her foot aloft in front of my face.

I inspected the proffered appendage: on the underside of her big toe was an oblong area of glistening red flesh that looked like a chunk of raw steak.

“Did you injure it?”

She shook her head. “It doesn’t hurt at all.”

I shrugged and said she must have grazed it. She wasn’t convinced, pointing out that she would remember if she had done that. She has great faith in plasters, though, and once it was dressed she forgot all about it. I dismissed it, too, assuming it was one of those things.

By the end of the next day, the pulp on the underside of all of her toes looked the same. As the doctor in the family, I felt under some pressure to come up with an explanation. I made up something about burns from the hot paving slabs around the pool. Gracie didn’t say as much, but her look suggested a dawning scepticism over my claims to hold a medical degree.

The next day, Gracie and her new-found holiday playmate, Eve, abruptly terminated a marathon piggy-in-the-middle session in the pool with Eve’s dad. “Our feet are bleeding,” they announced, somewhat incredulously. Sure enough, bright-red blood was flowing, apparently painlessly, from the bottoms of their big toes.

Doctors are used to contending with Google. Often, what patients discover on the internet causes them undue alarm, and our role is to provide context and reassurance. But not infrequently, people come across information that outstrips our knowledge. On my return from our room with fresh supplies of plasters, my wife looked up from her sun lounger with an air of quiet amusement.

“It’s called ‘pool toe’,” she said, handing me her iPhone. The page she had tracked down described the girls’ situation exactly: friction burns, most commonly seen in children, caused by repetitive hopping about on the abrasive floors of swimming pools. Doctors practising in hot countries must see it all the time. I doubt it presents often to British GPs.

I remained puzzled about the lack of pain. The injuries looked bad, but neither Gracie nor Eve was particularly bothered. Here the internet drew a blank, but I suspect it has to do with the “pruning” of our skin that we’re all familiar with after a soak in the bath. This only occurs over the pulps of our fingers and toes. It was once thought to be caused by water diffusing into skin cells, making them swell, but the truth is far more fascinating.

The wrinkling is an active process, triggered by immersion, in which the blood supply to the pulp regions is switched off, causing the skin there to shrink and pucker. This creates the biological equivalent of tyre treads on our fingers and toes and markedly improves our grip – of great evolutionary advantage when grasping slippery fish in a river, or if trying to maintain balance on slick wet rocks.

The flip side of this is much greater friction, leading to abrasion of the skin through repeated micro-trauma. And the lack of blood flow causes nerves to shut down, depriving us of the pain that would otherwise alert us to the ongoing tissue damage. An adaptation that helped our ancestors hunt in rivers proves considerably less use on a modern summer holiday.

I may not have seen much of the local heritage, but the trip to Italy taught me something new all the same. 

This article first appeared in the 17 August 2017 issue of the New Statesman, Trump goes nuclear