Martin Lewis, known for his insightful views on everyday items, has shared his latest opinion, and this time it's about the air fryer. In contrast to his previous warning about debit cards, Lewis is not particularly in favor of the popular electronic kitchen appliance.

Since the pandemic and rising living expenses, the air fryer has become increasingly popular. Touted as a healthier alternative to traditional ovens, these appliances are also promoted as being more cost-effective to operate.

However, it's possible that we may have prematurely embraced this compact electric oven, and it may not live up to all its advertised claims.

Martin Lewis' Honest Opinion On Air Fryers

In a recent episode of The Martin Lewis podcast, Martin shared that ovens can sometimes be more cost-effective than air fryers. Despite being 50 years old, he pointed out that microwaves offer consistent heat. In contrast, ovens heat up to their maximum temperature and then intermittently maintain that heat level in short bursts. Therefore, ovens do not continuously operate at full power.

Martin Lewis offered a practical example to illustrate how ovens can be more cost-effective than air fryers. He explained that if you were preparing a complete roast dinner and cooking several jacket potatoes, it would be more economical to bake them in the oven instead of microwaving five or six at a time.

This is because each additional object in a microwave requires more time to heat up, as a microwave heats each object individually.

It's important to note that this isn't a complete denunciation of air fryers. For instance, in the example given above, if you were only cooking one jacket potato, the air fryer or microwave would undoubtedly be more cost-effective. However, we can't always perform calculations to determine which option is more economical for a particular amount of food. Or can we?

The Mathematics Behind The Cost-Efficiency In The Kitchen

In response to the previous question, Martin Lewis offers a formula to help us calculate the cost-effectiveness of our kitchen appliances, but it comes with a caveat. He suggests finding the wattage of the appliance, determining how many kilowatts or a fraction thereof it uses, and then multiplying that by 34p ($0.42) per hour of use.

The only issue with this equation for heating appliances is that an oven typically consumes around 2,000W. Suppose you have a 1,000W microwave and you operate it for 10 minutes, which equates to one kilowatt-hour (KWH) over a sixth of an hour. Multiplying a sixth of 34p ($0.42) gives us about 6p.

Therefore, operating the microwave for that amount of time costs around 6p ($0.07). Nonetheless, it is still a highly useful equation. It's worth noting that the formula also works for air fryers.

The Money Edit also supports Lewis's claim. They found that the average operating cost of an oven is 21p, whereas an air fryer's is only 13.6p ($0.16). However, more powerful air fryers will have higher average operating costs. For instance, a 2000W air fryer costs an average of 34p per use.

They also agreed that the quantity of food is another crucial factor, as Martin Lewis had previously mentioned.

Therefore, Martin Lewis comes to a straightforward conclusion: "If you're cooking something small and uncomplicated, it's likely cheaper to use the microwave or air fryer."

This is not Martin Lewis's first time sharing his financial expertise. He has also spoken about the risks associated with debit cards. The financial expert believes that people should transition from using debit cards to credit cards because credit cards offer better fraud protection.