How much would you have to use the air fryer to recoup its cost in energy saving? I read that it's cheaper to batch cook - fill the oven and then freeze what you don't use immediately, in suitable sized portions for the number of people who will eat them. Obviously this assumes that you have a freezer with spare capacity. You can also do this with stews, stir fries etc cooked on the hob. Once frozen, you can either let them thaw naturally before you reheat them, or if you are in a hurry microwave them (not in the same container. You can briefly run the container under a tap to loosen the contents, then put them in another dish). I don't much like cooking, so I've been doing this for years, not to save money, but to get a load of cooking done in one go. I can see in some cases cooking in an air frier might be healthier, but only if you are currently eating a lot of unhealthy deep fried foods, I would have thought?