As the sun shone on millions of solar panels and unseasonable gusts turned thousands of turbine blades last Sunday, something remarkable happened to Britain’s power grid. For a brief period, a record 70% of the electricity for the UK’s homes and businesses was low-carbon, as nuclear, solar and wind crowded out coal and even gas power stations. That afternoon was a glimpse into the future, of how energy provision will look in 13 years’ time because of binding carbon targets. On what one grid manager called “stunning Sunday”, the carbon intensity of producing power – a key measure of progress towards climate goals – dropped below the “magic number” of 100g of CO2 per kilowatt hour for the first time. That’s the level that must be the norm by 2030, according to the government’s climate advisers. Yet last Sunday was just one of a run of striking records for renewable power in Britain that pose profound questions for conventional generators and the companies which manage power grids. On one Friday in May, solar power briefly eclipsed the UK’s eight nuclear power stations. The grid recently went without coal for an entire day for the first time, and the dirty fuel is now regularly absent from power supply for hours at a time. So far, the low prices seen in the UK during renewable output surges were relatively infrequent and had had limited impact, he said. But that will change as such events become more common – records will continue to be broken because of a pipeline of offshore windfarms being plugged into the grid. However, it is clear that the growth of renewables has made prices a lot spikier than they used to be. As well as low or negative prices during high wind and solar periods, prices can leap very high when wind doesn’t materialise as forecast. Day-ahead power prices in May averaged £41 per megawatt hour, but dipped just below zero early on 7 June during a period of high wind output. Prices also rose as high as nearly £83 in May.
Observer 17th June 2017 read more »