In a speech to the Environment Agency Mr Miliband said: “The public sector needs to do more: at the moment, the public sector owns 10 per of the land and generates only one per cent of renewable power.
“That is why our Partnership for Renewables with the Environment Agency is so important.
'At the moment there are plans to develop 500 MW of power, but we can be far more ambitious since there is the capacity for four times as much.
“It requires public sector leaders to be brave and see the opportunities. This will generate energy they can use and income, showing the public sector taking a lead in doing something we all will benefit from; tackling dangerous climate change.
“Of course not all of the land owned by the public sector is suitable for the current renewable technologies of wind and biomass, but as other technologies develop more public land could be used to build a low-carbon economy.”
Mr Miliband said national organisations, pressure groups and local authorities had a key role to play in setting the policy agenda ahead of next year’s United Nations Climate Change Conference in Copenhagen.
He said: “To live up to our promise on climate change, as a department and as a country, we need pace and we need our policy to be consistent with a progressive vision that can take people with us.
'But our aims cannot be achieved by government alone. For a global deal, we need action not just by governments but people around the world. We need people not just to come with us, but to push us for more.
“We need popular pressure - pressure on me, on local councillors, on our public services and businesses. “