Coal-fired power station. Train transporting coal to a power station (at upper centre). Coal-fired power stations burn fuel to heat water into steam. This steam then drives steam turbines which produce electricity. This steam is then cooled by water through heat exchangers and recycled back into the boilers. The cooling water is itself cooled by discharging it into cooling towers (short, wide towers at upper centre). Coal is a cheap and plentiful fuel but burning it releases sulphur dioxide and carbon dioxide which cause acid rain and global warming respectively. Photographed at Eggborough power station, Great Britain.