Climate change analysts Carbon Brief found more electricity came from the sun than coal from April to the end of September, in a report that highlighted the two technologies’ changing fortunes.

Solar had already eclipsed coal for a day in April and then for the whole month of May, with coal providing zero power for the first time in more than 100 years for several days in May. The latest milestone saw an estimated 6,964 gigawatt hours (GWh) generated by solar over the half-year, or 5.4% of the UK’s electricity demand. Coal produced 6,342GWh, or 4.7%.

The trend will not continue into winter because of solar’s seasonal nature, but the symbolic records reveal the dramatic impacts solar subsidies and environmental penalties for coal have wrought.

Increases in the carbon floor price last year have driven three major coal power plants – Longannet, Ferrybridge C and Rugeley – to close earlier this year. That came on top of a similar amount of coal power being closed between 2012 and 2014 because upgrading the stations to meet higher air pollution standards was deemed uneconomic.

A fourth coal plant, Eggborough near Selby in North Yorkshire, was expected to close in February but won a reprieve after it signed a 12-month contract to provide backup capacity to the grid. But the power station’s future after that contract is unclear, and its owners are now consulting on whether to demolish it and build a gas-fired one in its place.

According to trade body Energy UK, there are 10 coal power plants left in the UK. One is currently closed for conversion to biomass, one only operates in winter and another (Eggborough) only provides reserve power when needed.

Solar has grown rapidly in the last six years, though figures published last week by the Office for National Statistics showed installations had crashed after the government came to power and cut the industry’s subsidies.

A spokeswoman for the Solar Trade Association (STA) said: “This is a valuable milestone on the road to renewables overtaking fossil fuels. It is a testament to just how effective the British solar industry has been at installing clean and reliable power and at bringing down costs.”

The government said last week that solar power could produce electricity more cheaply than the price agreed for a new nuclear power station at Hinkley Point, but officials suggested solar would have additional costs for the National Grid.

But a new report for the STA, published on Tuesday, concluded that integrating many more solar panels into the grid would not add excessive costs to accommodate the fact the sun doesn’t always shine and backup power is required to cover solar.

“With intermittency costs today of around £1.3/MWh for solar [with around 10-12GW of solar installed], increasing to £6.8/MWh with a substantial 40GW of solar on the system by 2030, we would suggest these costs do not provide a strong argument against the further build out of renewable generation,” said the report, by the consultancy Aurora.

Severin Carrell

This article first appeared on the Guardian

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