The Coalition has indicated it may dump Climate Change Authority chairman and former state Liberal MP Matt Kean if it wins the next federal election after his agency warned the opposition’s proposal to power the country with nuclear energy would cause a dramatic increase in carbon emissions.

The authority on Monday said the Coalition’s proposal to keep coal and gas power plants running for longer until seven government-owned nuclear reactors were built would cause Australia to miss its target to cut emissions by 43 per cent on 2005 levels by the end of the decade.