The Home Office has achieved a reduction of 15 per cent. on the non-Prison estate between 1990–1991 to 1999–2000 in energy consumption (kwh/m 2 ), taking into account weather changes and estate changes. The Home Office (non-Prison estate) has benchmarked all key office buildings, with a view to reducing their individual consumption. The Prison Service has invested £300,000 in energy efficiency schemes. It circulates a regular 'Energy News' bulletin to all prison establishments to encourage energy saving schemes, and the Construction Unit frequently gives presentations to outside organisations to publicise the Prison Service's initiatives in the field of energy reduction.