Buying the right kettle can be a difficult choice but an energy efficient kettle will pay off in the long run, the British boil their kettles on average 4 times a day so buying an energy efficient kettle should be a priority. However, simple steps such as only adding the amount of water you actually need to your existing kettle can have the same dramatic impact as you don’t waste energy heating surplus water. An increase in the power of modern kettles, increasing water capacities and keep-warm functions combine to mean modern kettles are much more energy intensive than before. Either boiling less water with your existing kettle, or buying an energy efficient new kettle, should be a priority though as it’s an easy way to conserve large amounts of energy at work and home.
Kettles are normally rated in terms of their power (i.e. 3000 Kw) - the more powerful the kettle then the faster it boils any given quantity of water. The kettle is also the cooking device 
that consumes the most energy in the home, 29% compared to 26% for electric ovens and 23% for electric hobs. Modern Electric kettles have the potential to be the most energy efficient method of boiling water, but because of the difficulty in judging the precise quantity needed we actually waste large amounts of energy every year in boiling and reboiling unnecessary amounts of water.
There is a huge range of kettles on the market all trying to prove their green credentials such as the “Eco kettle” and the Tefal “Quick Cup”, however there have been very few actual innovations when it come to heating water. One of the above relies upon having to only heat the water needed each time which in turn means less energy consumed and less time for the water to boil. The other only heats the water to just below boiling point, therefore consuming less electricity.
A report from the Ethical Consumer is full of tips on which types and models of kettle are best in terms of their relative environmental impact. For example:
- Jug kettles with a hidden element are the most efficient
- Stainless steel kettles last longer than plastic
- Insulated 'Coolwall' kettles need reboiling less often
- Traditional stove-top kettles for gas cookers use slightly more energy than a jug kettle to boil the water, but are a better choice in terms of carbon emissions because of the inherent inefficiency of conventional electricity production.
- However, kettles run on eco-electricity have the lowest environmental impact of all.
More detailed information on trends in kettle technologies and their environmental implications can be found in the relevant section in the Governments Market Transformation programmes document 'Trends in kettle type and usage and possible impact on energy consumption'