Products are loaded from the market daily. New products are usually added to the database in 1-2 days.

Information from official sources is used to calculate the initial average lifetime energy cost of a product that is shown.

Power consumption: This is taken directly from the product fiche published by the manufacturer.

Average usage: The average usage for different categories is taken from a report by the Energy Saving Trust.

Average lifespan The average lifespan for each category is also taken from a report by the Energy Saving Trust.

Average tariff: This is taken from data published by Eurostat.

Average annual tariff increase: Again taken from Eurostat, historic data for tariffs over the last 10+ years is reviewed to determine the average annual increase in electricity costs.

To see the actual values you can click on the help icon (?) in the tool.

All of the savings, ratings and comparisons are based on like-for-like products, which in general terms is the size or capacity of a product. Examples of classifications:

Dishwashers: Classified by size: compact, slimline or full size.

Freezers: Classified by type and capacity: chest 100-199 litre, chest 200-299 litre, undercounter, upright 100-199 litre, upright 200-299 litre, etc.

Fridge Freezers: Classified by type and capacity: 50/50 100-199 litre, 50/50 200-299 litre, american 500-599 litre, american 600-699 litre, etc.

Fridges: Classified by type and capacity: larder undercounter, larder 100-199 litre, larder 200-299 litre, ice-box undercounter, ice-box 100-199 litre, ice-box 200-299 litre, etc.

Tumble Dryers: Classified by capacity: 7 kg, 8 kg, 9 kg, 10 kg, etc.

Washer Dryers: Classified by wash capacity: 7 kg, 8 kg, 9 kg, 10 kg, etc.

Washing Machines: Classified by capacity: 7 kg, 8 kg, 9 kg, 10 kg, etc.

It’s essential to compare like-for-like as, for example, it does not make sense to compare the running costs of a 6 kg washer with a 10 kg washer, as the larger capacity washer is likely to use more energy.

For refrigeration, as there are no standard sizes, products are sub-categorised by type and capacity for comparison. For example, it doesn’t make sense to compare a larder fridge with a model that has an ice-box, because freezers use much more energy. Similarly it doesn’t make sense to compare a 50/50 split freezer with a 70/30 split, as the model with 50% freezer will use a lot more energy than the one with 30% freezer.

We use the least efficient product for two reasons. Firstly, the cheapest products are generally the least efficient and as many of us tend to buy cheap to save money, this represents a good benchmark for comparison.

Secondly, one of the best ways to understand how energy efficient a product is compared to others, is to see where it sits in the range for all products in the market. By comparing with the least efficient model, you can see just how wide the range of energy costs is for different products and where a particular product sits in the range.

When you open the tool for the first time you will see the range of lifetime energy savings. If you want to see the energy costs you can simply click on the ‘Show energy costs’ button.