The cost of building five new power stations and an associated gas plant in the north of Western Australia has increased by 76 per cent to an estimated $265 million, adding to the long list of projects suffering big cost blow-outs.

The cost of building five new power stations and an associated gas plant in the north of Western Australia has increased by 76 per cent to an estimated $265 million, adding to the long list of projects suffering big cost blow-outs.