Buying an oven: what matters for cooking and for the bill

What size of oven do you actually need?

Pick the smallest cavity that fits your largest regular dish, because every litre of space has to be heated each time you bake.

Most built-in ovens fit a standard 60 cm niche; compact models for 45 cm high niches have smaller cavities. The label states the usable volume in litres for each cavity, and a double oven carries one label per cavity. A small second cavity is a practical saving if you often cook for one or two: a pizza or a tray of vegetables then heats a much smaller space.

The table groups ovens by type and cavity volume, as in our oven overview. Consumption per use is only comparable within one size band.

Fan or conventional heating: which is cheaper?

Fan heating usually needs less energy per use, and the label shows both figures so you can see the difference for each model.

The fan spreads heat evenly, so recipes generally work at a lower setting, often around 20 °C below the conventional temperature, and you can bake on several shelves at once. A batch of biscuits on two trays in one fan cycle uses less than two separate conventional cycles. Conventional top and bottom heat still has its place for some cakes and bread, but for everyday use the fan figure is the relevant one.

That is why our yearly costs use the fan-heating value per use, multiplied by 100 uses a year by default; change the number in the bar above. Where a model declares only a conventional figure, we use that. The most efficient ovens are ranked by the fan value.

Preheating only when a recipe needs it and switching off a few minutes early to use the residual heat both save energy without affecting most dishes.

What does an oven’s energy label actually measure?

It measures the energy needed to heat a standardised load soaked with water in one cycle, once with conventional heating and once with fan heating, separately for each cavity.

The class on the A+++ to D scale is calculated from the better of the two modes and the cavity volume, under Delegated Regulation (EU) No 65/2014. Since February 2019 the ecodesign rules (Regulation (EU) No 66/2014) have required an efficiency index below 96 for new ovens, which falls inside class A; in a double oven, the second cavity may be in class B. In practice, the class therefore separates new ovens far less than the kWh per use does.

Some ovens have no energy label at all: ovens with a microwave function, ovens heated mainly by steam, very small ovens, countertop ovens under 18 kg that are not built in, and ovens made only for bottled propane or butane. The oven label explainer covers each field.

Is a pyrolytic self-cleaning oven worth it?

It is worth it if you hate scrubbing, but each cleaning cycle uses electricity that the energy label does not include.

Pyrolysis heats the empty cavity to around 500 °C for one to several hours and turns grease into ash that you wipe out afterwards. How often you run it decides its cost: after every roast is very different from twice a year. The alternatives use less energy but clean less thoroughly: catalytic liners absorb fat during normal cooking and lose effect over the years, and steam or “hydrolysis” programmes soften dirt at low temperature before you wipe it off.

Should you choose a gas or an electric oven?

Decide by what is connected in your kitchen and by your local gas and electricity prices, because the two labels measure different fuels.

A gas oven’s label gives consumption per cycle in megajoules and in kWh of gas (1 kWh equals 3.6 MJ). That is gas, not electricity, so we show the declared values and class but do not convert them into an electricity bill. Comparing the two means multiplying each figure by its own price per kWh.

How long will it last, and can it be repaired?

Ovens are simple appliances that are often repairable, but no EU rule obliges manufacturers to stock spare parts for them.

Unlike fridges, washing machines or dishwashers, ovens have no ecodesign requirement on spare parts or repair information, and they are not covered by the EU right-to-repair directive. Heating elements, fan motors, thermostats and door seals are the parts that typically wear out and can usually be swapped by a technician. Before buying, check whether the manufacturer publishes how long it supplies parts, and keep the model number from the rating plate inside the door frame.

Does replacing an old oven save money?

Rarely on electricity alone, because an oven used a few times a week consumes relatively little; replace it when it is broken or no longer cooks well.

1. Find the old oven’s kWh per cycle from its label or manual.
2. Subtract the fan figure of a new model of similar size.
3. Multiply by your uses per year and your price from the electricity prices by country.
4. Divide the new oven’s price by that yearly saving and compare the result with the oven’s expected life.

The total cost of ownership calculator does this with your figures. If you bake daily or cook for a large household, the saving grows in proportion.

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