The world’s use of coal fell by the largest amount on record last year as the fossil fuel that powered the industrial revolution was struck by tumbling US gas prices and another year of dwindling consumption in China.  BP’s latest world energy review showed 2015 had been “an annus horribilis for coal”, said the oil and gas group’s chief economist, Spencer Dale.  Global consumption and production levels for coal plunged by the biggest amount since at least 1980, while prices fell about 20 per cent.