The ESB has increased its stake in the Coolkeeragh Group, which operates a power station in Derry, from 15 to 40 per cent, at a cost of £1 million sterling (€1.52 million).

The two companies also announced that they will build a £150 million sterling power station in Derry if a new gas pipeline is built between Belfast and the city to serve the plant.

The Northern Ireland electricity regulator, Ofreg, is currently assessing applications from three companies to build such a pipeline.