The share of Great Britain’s electricity generated by burning fossil fuels plummeted to unprecedented lows this month, ahead of plans to begin running a “zero-carbon grid” for short periods from next year. Electricity generated by burning gas and coal fell to a record low of just 2.4% for an hour at lunchtime on Monday 15 April, according to an analysis of data from National Grid’s electricity system operator (ESO). The same data has revealed that earlier this month the share of fossil fuels in the generation mix taken over an entire day fell to a record low of 6.4%, on 5 April. Related: Energy mix: how is electricity generated in Great Britain? The findings lend support to the aims of the ESO to begin the “groundbreaking and world-leading” step of running a zero-carbon electricity grid for Great Britain for short periods from next year. Craig Dyke, the director of system operations at the ESO, said Britain had made “excellent progress” towards this goal and there had already been periods when the grid had run safely on more than 90% zero-carbon power. The new records mark a dramatic shift from 15 years ago when gas and coal power plants made up...