Mr Clegg will today announce the government's new investment plan in energy efficiency.
Last year many environmentalists were dismayed by Chancellor George Osborne's comment the Tory conference that, while the Government would invest in green energy, "we're not going to save the planet by putting our country out of business".
And the Treasury is understood to have demanded cuts of 25% in subsidies for onshore windpower in a tussle between Mr Osborne and Liberal Democrat Energy Secretary Ed Davey, which ended last month with a 10% cut but question marks hanging over the 2030 target for decarbonising the economy.
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Cloud restricting sunny skies today
A number of wild baby animals have died after being illegally picked up by people thinking they had been abandoned - or wanting a selfie.
Any car registered before 1997 will be affected by the ban - and the UK is about to follow suit with the introduction of Clean Air Zones.