The short answer
An efficiency class compares a product within its appliance-category and label-version rules. It does not supply a household running cost. Check the declared kWh, capacity and programme, then apply your tariff; old A-plus classes and rescaled A–G classes cannot be treated as interchangeable energy quantities.
What the class tells you
An energy class compares a product’s efficiency within the rules for its appliance category. It is useful for narrowing a shortlist, but it does not supply an electricity price or a household’s usage pattern.
The European Commission explains the rescaled A–G label. Several household categories moved to this scale in 2021; tumble dryers moved later. Check the product category and label version before interpreting a letter.
Why a better letter is not a complete cost comparison
Your running cost depends on the stated energy consumption and your tariff. Capacity and the task you need the appliance to perform also matter. A compact appliance and a much larger one may not provide equivalent service even when their letters are easy to compare.
Here is an illustrative annual-energy comparison at €0.30 per kWh:
| Candidate | Annual energy | Electricity cost |
|---|---|---|
| One suitable appliance | 180 kWh | €54.00 |
| Another suitable appliance | 240 kWh | €72.00 |
| Difference | 60 kWh | €18.00 per year |
The calculation needs no assumed conversion from letters to kWh. If the lower-consumption option costs €150 more to buy, the simple extra-price payback is €150 ÷ €18, or about 8.3 years. That is a scenario, not a prediction of lifespan.
Do not translate an old plus rating by guesswork
An old A+, A++ or A+++ label and a rescaled A–G label are different comparison systems. Use the label and information sheet for the exact model and its applicable regime; do not assign a new class simply by deleting the plus signs.
If the two energy figures also use different test bases, first establish whether they describe compatible conditions. Mathematical unit conversion cannot correct a different test programme.
A useful shortlist checklist
Check the model identifier, usable capacity, consumption figure and unit, label version, programme where relevant, noise information and purchase price. Then compare purchase and electricity costs.
For a fridge-specific walkthrough, read the fridge energy-label guide. For a model information sheet, use the EPREL guide.