I've been looking up some facts about the benefits of not filling the kettle each time you boil it. In a speech by the Rt Hon David Miliband MP at the National School of Governance conference, Queen Elizabeth II Conference Centre, London - "Public services and public goods: lessons for reform" - 6 June 2006 he said:
"If everyone boiled only the water they needed to make a cup of tea instead of filling up the kettle every time, we could save enough electricity in a year to run more than three quarters of the street lighting in the country."
And a press release from the Department for Environment, Transport and the Regions (DETR) said:
"Each time we boil the kettle we use more water than we need, we also waste valuable energy and contribute to climate change. On average, we could all save 90 seconds each time we boil a kettle - by putting in only the amount of water we need. Such a simple action would also cut household electricity bills -
overfilling each time we boil wastes enough energy in a week to light our house for a day or run a TV set for 26 hours."