Energy Labels: Energy consumption kWh/Cycle

The second section on washing machine energy labels shows energy usage of washing machine. Here you can find out the amount of energy (electricity) that the washing machine is likely to use on a particular wash cycle. The figure is based on a 60 degree cotton cycle – even though most people rarely use it.

The most common wash cycle in use is 40 degrees and we are being encouraged to wash at 30 degrees. Therefore if you wash mostly at 40 degrees the energy consumption figures quoted will be higher than your actual costs. It still provides a method of comparing different washing machines, but it appears that some manufacturers have been playing the system which means the figures may be useless.

It’s possible that a washing machine is getting lower energy usage figures on the eco label because it isn’t heating the water up to anywhere near 60 degrees (which is what uses most of the electricity) as described here – Washing machines not delivering right temperature.

So it might use less energy but it may only be heating up (in the worst example) to 43 degrees.

Figures and stats are commonly useless yet everyone seems obsessed with them

The points raised in previous sections still apply here. What if you compare two washing machines, and one costs £10 per year more to run than the other? Does that mean the cheaper-to-run one is a better buy? You may instinctively choose the “cheapest to run”, but the running costs of a washing machine can’t be factored down to simple electricity charges.

The running costs of a washing machine over its lifetime must include all repairs and how long it lasts too. Clearly these can’t be factored in so easily but if a “more economical” washing machine is far less reliable then there’s little point saving £10 a year in energy costs. Again these figures are less important than finding a good quality reliable washing machine. Even the worst washing machine in the shops can have a good eco label because manufacturers make sure they do (eg. Washing machines not delivering right temperature).

How to use the Energy consumption kWh/Cycle figure

Electricity is charged in kWh (kilowatt hours). 1 kWh is the amount of electricity used by an appliance rated at 1000 watts in one hour. If you switch on an electric fire with an element rated at 1000 watts and left it on for 1 hour you will have used 1 kWh of electricity.

If you switched two electric fires with 1000 watt elements on for half an hour you would use exactly the same amount of electricity – 1kWh. Drawing 1000 watts for an hour uses the same amount as drawing 2000 watts (twice as much) for half an hour (half the time). For a 100 watt light bulb to use 1 kWh of electricity (also known as 1 unit of electricity) it would need to be on for 10 hours (10 x 100 = 1000 = 1kWh).

The figure in the energy label above is 0.95 This is how many kilowatt hours (kWh) the washer should use on a whites cottons 60 degree wash cycle. If it used 1 whole kilowatt hour the figure would be 1.0, this figure is almost 1.0 kWh (95% of a kWh).

You need to find out how much you are being charged per kWh to work this out into a cash figure which should be on your electricity bill.

This is easier said than done because of the complexity of modern electricity tariffs but if you know the figure just multiply the two to get a price. On the Energy Saving Trust site they quote 7 pence per kWh but this is miles out of date. On another section they use the updated figure of 12.12p/kWh which is closer to average current rates but these rates are rising,and different tariffs can vary a lot. NOTE: Energy prices have shot up since I originally researched this article.

If we use 12.12p/kWhs as an average cost you would multiply 0.95 by 12.12 arriving at a cost of 11.51 pence to do a 60 degree cottons wash. If the label said the washing machine used 1.2 kWh for a 60 degree wash the cost would be 14.54 pence (1.2 x 12.12).

A more substantial saving in energy costs can be found by simply paying less for the energy

Read my full article Reducing energy costs of washing machines & other appliances

Related:

• Part 1: What do the energy labels on washing machines mean? Energy Efficiency Ratings
• Part 2: (this page is part 2)
• Part 3: Washing performance ratings on eco labels
• Part 4: Final Part – spin drying performance, water consumption & Noise levels
• Eco-labels suggestion
• How designing for eco labels can be misleading
• Do we really need to dump our old inefficient appliances to save money and the world?