For washing machines the energy efficiency scale is calculated using a cotton cycle at 60°C (140°F) with a maximum declared load. This load is typically 6 kg. The energy efficiency index is in kWh per kilogramme of washing.
With advances in energy efficiency nearly all washing machines are now A rated and so A+ and A++ ratings have been introduced. So is it worth basing a purchasing decision on the energy rating? In the table below are some examples of the annual running costs of 3 different washing machines rated A, A+ and A++.An A++ machine saves approximately 4pence per wash or £ 10 per year over an A rated machine. This difference is pretty small, especially if the A++ rated machine costs £ 100 more! Also reliability and longevity need to be taken into account. The running costs of a machine are not just energy consumption, it includes repairs and how long it lasts before it has to be replaced.
| Energy rating | Energy consumption kWh/cycle | Cost per wash | Cost per year |
| A | 1.52 | 18 pence | £ 66 |
| A+ | 1.36 | 16 pence | £ 59 |
| A++ | 1.2 | 14 pence | £ 52 |
| The annual running costs are based on a single wash each day | |||
Because the energy cost differences are so small; it should not be used as the basis for a buying decision. The number one priority should be to buy a good quality reliable machine that fits your budget. A washing machine that breaks down regularly, requires expensive spare parts and needs replacing far too soon is bad for your wallet and the environment, even if it is A+ rated.
