The Department for Transport has spent the following amounts on gas and electricity: £ 2010-11 2011-12 Gas 830,763 1,467,647 Electricity 6,255,277 7,051,395 During this period the following providers have supplied gas and electricity: Gas British Gas; Corona; E.ON; Npower; Powergen; and Scottish Power. Electricity Alliance; British Gas; EDF; E.ON; Npower; Opus Energy; Powergen; Scottish Hydro; Scottish Power; Southern Electric; and Swallec. The Department closely monitors and manages energy consumption in order to meet targets from the Greening Government Commitment and the Carbon Reduction Commitment Energy Efficiency Scheme; and has undertaken various site specific measures to reduce the cost of electricity and gas provision: Energy efficiency measures To reduce the amount it uses in line with the Governments Greening Government Commitments by increasing the efficiency of its estate. This includes using a gas powered combined heat and power (CHP) to produce a proportion of its own electricity and make use of the excess heat. Purchasing The Department uses Government Procurement Services frameworks to purchase its electricity and gas. This bulk buying through central Government allows for value for money purchasing and reduces price volatility. Financial scrutiny The Department ensures that bills are scrutinised to ensure accuracy and to minimise the risk of being overcharged for supply. Rationalisation of the estate By reducing the amount of office space we use, and reducing energy loss through improved insulation, improved heating and lighting controls/energy efficient lighting. Installation of renewable energy technology Wind turbines installed at three sites, photovoltaics panels at one site and solar water heating one site.