The world is on the brink of a big switch from gas to coal as the preferred fuel for power stations, according to projections from Alstom, Siemens and General Electric, the three biggest power equipment makers.

Independent forecasts from France's Alstom and Germany's Siemens, made available to the Financial Times, show that about 40 per cent of the orders for electricity turbines in the next decade will be for coal-powered units, with the share of gas-fired plants falling to between 25 per cent and 30 per cent.