Calculating the cost of running various appliances - kw vs kWh

Freebird53

My guess (without doing actual testing) is that with reference to what Sparkygrad and Dolor said, is that an 'air fryer' won't save a great deal of energy.

I've noticed after reading several ads for them, that 'saving energy' was not mentioned once.

Also, if you factor in the initial cost of the 'air fryer', including it's likely lifespan compared to that of an 'existing' oven, is it really cost effective?

Apodemus

Xbigman said:

This is what energy monitor plugs are for. There's nothing to calculate, you just measure the actual usage. With things like ovens that are hardwired you have to make a bit more effort and read your actual meter before and after use. If you turn everything else off you can get a very close idea of usage.



Darren

I've got an Owl monitor, which clips round the incoming electricity cable and gives similar info to a smartmeter IHD.  One interesting feature is that you can set an alarm to notify you when you exceed certain kW levels.  Trying to keep below a 5kW level can be a challenge at times, and even a 10kW alarm will go off when someone adds the electric shower to the usual household background.

facade

I have a powermeter plug, (I think it was from Aldi donkeys years ago) and today's task is to see how much energy my airfryer used to cook chip from frozen- it takes 20 minutes and the fryer is rated 1400W, so that will be 1.4x 20/60 = 0.47 kWh if it is on 100%, I will see....

I would suggest getting a powermeter plug, but they are about £15 now for one that probably won't set on fire or electrocute you, which is a lot to find out how much something costs to run when you probably can't stop using it, better to read the meter before & after.

[Deleted User]

Freebird53 said:

My guess (without doing actual testing) is that with reference to what Sparkygrad and Dolor said, is that an 'air fryer' won't save a great deal of energy.

I've noticed after reading several ads for them, that 'saving energy' was not mentioned once.

Also, if you factor in the initial cost of the 'air fryer', including it's likely lifespan compared to that of an 'existing' oven, is it really cost effective?

An Airfryer should use a lot less energy as it is heating a very small area to a given temperature. I agree though that we are all guilty of not taking life cycle costs into consideration. 

For example, people buy £60 eTRVs more for their convenience than for their energy saving. The same result can be obtained by turning down a manual TRV that has a much greater lifespan and doesn’t need batteries!

Cardew

The best example demonstrate the points in the posts above is a large freezer. 

An example has the compressor rated at 290 watts(0.29kW)

Although the freezer is left on 24/7 if the compressor ran 24/7 it would use 2,540kW a year.  However depending on how/where it is used a typical annual consumption might be 200kWh - 300kWh

Freebird53

Fascinating subject!

I found an article on the Daily Mirror pitting an air fryer against a fan oven. It was an interesting read....

I then found a recipe on the BBC for cauliflower wings, which was also interesting. 

ariarnia

an air fryer is basically just a small fan oven isn't it? the only difference i can really tell is the fan is at the back on a fan oven and top in an air fryer. 

northlondonlynn

Yes, it's exactly that. Mine is roughly similar wattage to my combi-microwave (which has a convection oven mode), but it's a much smaller space so it heats up more quickly and cooks more quickly. That's why I bought it - for cooking a small amount of food, it's cheaper to use the air fryer than to heat up your main oven. If I was doing an entire roast dinner I'd use the main oven.

facade

I tested my airfryer (Actifry Original) and it took 0.32 kWh to cook chips, which is about 11p.  The power switches between 50W and 1500W.

So it used about 2/3 of the estimate because it cycles the heater on & off.

I didn't buy it to save money, I bet it still hasn't paid for itself yet, but it is less messy than the deep fryer.

northlondonlynn

Freebird53 said:

My guess (without doing actual testing) is that with reference to what Sparkygrad and Dolor said, is that an 'air fryer' won't save a great deal of energy.

I've noticed after reading several ads for them, that 'saving energy' was not mentioned once.

Also, if you factor in the initial cost of the 'air fryer', including it's likely lifespan compared to that of an 'existing' oven, is it really cost effective?

Air fryers (such a misleading name) are cheaper for cooking or re-heating small portions. My main oven is about 77l capacity. I use it when I'm cooking multiple dishes, eg a roast dinner. But it wouldn't be economical to use such a big space for a single dish - that's where the air fryer comes into its own. Also, It takes  8-10 minutes to pre-heat my main oven to 180°. The air fryer gets to the same temperature in 2-3 minutes. That's a cost saving in its own right.