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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Donald Trump vs Barack Obama: How the inauguration speeches compared

We compared the two presidents on trade, foreign affairs and climate change – so you (really, really) don't have to.

After watching Donald Trump's inaugural address, what better way to get rid of the last few dregs of hope than by comparing what he said with Barack Obama's address from 2009? 

Both thanked the previous President, with Trump calling the Obamas "magnificent", and pledged to reform Washington, but the comparison ended there. 

Here is what each of them said: 

On American jobs

Obama:

The state of our economy calls for action, bold and swift.  And we will act, not only to create new jobs, but to lay a new foundation for growth.  We will build the roads and bridges, the electric grids and digital lines that feed our commerce and bind us together.  We'll restore science to its rightful place, and wield technology's wonders to raise health care's quality and lower its cost.  We will harness the sun and the winds and the soil to fuel our cars and run our factories.  And we will transform our schools and colleges and universities to meet the demands of a new age.

Trump:

For many decades we've enriched foreign industry at the expense of American industry, subsidized the armies of other countries while allowing for the very sad depletion of our military.

One by one, the factories shuttered and left our shores with not even a thought about the millions and millions of American workers that were left behind.

Obama had a plan for growth. Trump just blames the rest of the world...

On global warming

Obama:

With old friends and former foes, we'll work tirelessly to lessen the nuclear threat, and roll back the specter of a warming planet.

Trump:

On the Middle East:

Obama:

To the Muslim world, we seek a new way forward, based on mutual interest and mutual respect. To those leaders around the globe who seek to sow conflict, or blame their society's ills on the West, know that your people will judge you on what you can build, not what you destroy. 

Trump:

We will re-enforce old alliances and form new ones and unite the civilized world against radical Islamic terrorism, which we will eradicate completely from the face of the earth.

On “greatness”

Obama:

In reaffirming the greatness of our nation we understand that greatness is never a given. It must be earned.

Trump:

America will start winning again, winning like never before.

 

On trade

Obama:

This is the journey we continue today.  We remain the most prosperous, powerful nation on Earth.  Our workers are no less productive than when this crisis began.  Our minds are no less inventive, our goods and services no less needed than they were last week, or last month, or last year.  Our capacity remains undiminished.  

Trump:

We must protect our borders from the ravages of other countries making our product, stealing our companies and destroying our jobs.

Protection will lead to great prosperity and strength. I will fight for you with every breath in my body, and I will never ever let you down.

Stephanie Boland is digital assistant at the New Statesman. She tweets at @stephanieboland