Energy ratings labels on appliances are generally given to products based on size categories. The idea is to enable you to compare between two similarly sized products.
This means two differently sized appliances with the same energy rating may use quite different amounts of electricity. For instance an A rated 180-litre fridge freezer could cost only £39 a year to run whereas a larger 525-litre fridge freezer with a better A+ rating would cost £54 a year to run. That’s £13 a year more.
In trying to save energy it is therefore best to look for the product with the best energy rating for the size of product you require.