The Morrison government's generator underwriting scheme is losing a race against time to be completed before the election campaign begins in April, making it the second major energy policy to fall foul of the political timetable.

The plan for the government to underwrite a new firm generation plant is getting caught up in internal coalition differences over energy policy with Victorian Liberals and some NSW Liberals rejecting a push by their Queensland colleagues for a coal-fired power station to be included in the scheme.