There are a number of different labels that can help you determine how energy-efficient a product is.
All large household appliances, such as washing machines and refrigerators, are now required by EU Law to carry energy ratings. The ratings tell you how much energy the product uses on a sliding scale from green to red. Products in the green bracket are the most energy efficient.

For products not covered by the EU legislation – for example TVs and other home electronics – look for the Energy Saving Trust’s ‘Recommended’ label. Some products available via Ice are too new to have been put through the standardised rating tests for energy-efficiency. In these cases, Ice researches the product and reviews its characteristics to ensure it is suitable.
Don’t forget that by buying an energy-efficient product, you will also save money on your electricity bill. Although it may be more expensive to buy initially, it should save money over its lifetime. For example a modern, energy-efficient dishwasher will use approximately 20% less energy than an older less efficient model. Over the course of a year, this energy saving will result in a £12 saving on your electricity bill and a 40kg reduction in carbon emissions.
For more details on UK energy policy, please look at the linked report UK Low Carbon Transition Plan.