The Mathematics Behind The Cost-Efficiency In The Kitchen

To the previous question, Martin Lewis actually provides an equation that will give us the answer, along with its problem. “General equation is, find the wattage of an item, then work out how many kilowatts or what fraction of a kilowatt it’s using, then multiply that by 34p ($0.42) per hour of use. […]

The problem with the equation for heating equipment is an oven is going to be about 2,000W. If you had a 1,000W microwave and you put it on for 10 minutes, one KWH for a sixth of an hour, a sixth of 34p ($0.42) is about 6p, shall we say? So it’s 6p ($0.07) turning the microwave on for that amount of time. So yes it’s a very useful equation”. Just as a clarification, the equation works for air fryers as well.

Lewis even gets backing from a different source: The Money Edit. They conclude that the average running cost of an oven is 21p, whereas that of an air fryer is only 13.6p ($0.16). However, more powerful air fryers will naturally have higher average running costs. Some, like the 2000W one, cost 34p per average use. They also support the fact that the quantity of food is another important factor as Lewis explained.

As such, Martin Lewis draws a simple conclusion: “If you’re cooking something small and simple in there, it’s probably cheaper in the microwave and similarly the air fryer.”

This is not the first of Martin Lewis’ expert opinion on financial matters. He also discussed the danger behind debit cards in general. The money marketing expert also believes that one should move from debit cards to credit cards because credit cards offer fraud protection.