Ed Milliband is heading up the UK government's newly-created Department of Energy and Climate Change, which brings together two separate departments.
Miliband as secretary of state for the new department is tasked with ensuring the UK meets its EU 2020 target to cut greenhouse gas emissions by 20% and raise the UK's renewables contribution from 2% to 15% of the UK's total energy supply.
The UK's Renewable Energy Association (REA) said Ed Miliband has his work cut out meeting tough European Union environmental targets.
'This will require Mr Miliband to extend the policy portfolio way beyond the narrow range considered by his predecessors,' said the director general of the REA, Philip Wolfe.
Wolfe said 'In particular we look forward to measures for renewable heat, which can be included in the renewable energy tariff being considered in the current Energy Bill.
'He also needs to overcome obstacles delaying renewable technologies like wind, bioenergy and marine renewables, and to adopt a more robust approach to renewable transport fuels and decentralised energy technologies like solar energy and heat pumps.'
Previously the Department for Business, Enterprise and Regulatory Reform (Berr) had responsibility for the UK's energy strategy and the Department for Environment, Food and Rural Affairs (Defra) was tasked with reducing greenhouse gases and getting energy used more efficiently.
Wolfe added 'We are delighted that the government has acted on our suggestion that energy now needs its own department and cabinet minister. We have been calling this for some time, most recently in our submission last week to the Renewable Energy Strategy'.
The REA is the UK's leading renewable energy association with over 500 members, including all major UK energy companies and independent producers.