Energy Efficient Appliances: Upgrading to A rated white goods

ABrass

For the air fryer you could measure it's actual power draw with a Power Angel or other measuring plug. It's much harder to measure for the oven of course but if you replicate the test cycle process then you would get a good comparison.

But that's still trying to use a standard cooking scheme over two different devices that serve different purposes. I don't own an air fryer but would you really ever be using it to cook something for an hour?

zeupater

Screwdriva said:

Alnat1 said:

Looking at it from a green point of view, it might save a little energy but you've probably sent the old oven that was still working to landfill.

The old oven no longer functions. 

zeupater said:

To perform a sanity check ... the oven spec is 3500W using 1.09kWh per cycle, so if the cycle is ~1hr then that would be 7minutes at 3500W followed by 25% of the remaining 53 minutes (20.25mins total), that's 1.18kWh, so pretty much in line with the 1.09kWh per cycle as per the appliance label .... 

Unless I've misread the label, the AEG oven consumes 0.52 kWh per cycle in fan mode, which is the only mode we use (1.09 kWh is standard oven only mode)

Hi

The issue at hand would be the comparison based on the sausage rolls ... if the understanding of the label is that the oven would consume 520Wh to heat the sausage rolls then that's pretty much in line with the 467Wh calculated earlier, but this means that it simply moves the energy usage comparison from approx 4.5x to 5.2x, so whichever figure is used, the oven is far more energy inefficient for the specific task (heating sausage rolls) than an air fryer would be ..

The problem as I see it is, as already mentioned, the definition of a 'cycle' as per the efficiency label, how that actually applies to appliance usage in everyday conditions, and most importantly, what consumers would reasonably expect the rating on the label to be describing  ....

Here's a link to the UK version of EU legislation regarding cooker appliance labelling ....  https://www.legislation.gov.uk/eur/2014/65 ... where the definition for a cycle is " ‘cycle’ means the period of heating a standardised load in a cavity of an oven under defined conditions;", the issue is that the standardised load is based on the cavity size and the cycle is based on the time to raise the internal temperature of the oven cavity to a standardised temperature with the standardised load (effectively a wet towel of a certain mass) for that particular cavity volume in it.

Now, in full possession of the information supporting the efficiency label we're still left with the quandary .... how does this relate to efficiency when heating part loads, such as sausage rolls? .. and most importantly .. what does the label really tell the consumer apart from the ability to compare one appliance with another appliance with effectively the same capacity? ...

The way I read it is that the test conditions and therefore the efficiency label simply encourages the manufacture & purchase of light internal thermal mass appliances so as to reduce pre-heat times and raise cavity temperatures as quickly as possible so that whatever thermal energy is available in the cavity can be focussed on raising the temperature of whatever the load is that's being heated ....

Effectively it looks a little like knowing the 0-60mph acceleration and not the average mpg ... of course an expensive lightweight sports car wins out on one over a standard priced family car, but how does that translate to how fuel efficiently a trip can be made after 60mph has been reached ... to me it doesn't & that's what I attempted to convey in the previous post ".... my suggestion is that everyone should spend a little effort looking at how it's tested & calculated and what that actually means when translated to actual cooking/heating of typical products in the real world in any particular capacity oven ...."! 

HTH - Z

Raxiel

Alnat1 said:

I don't own an air fryer. Considered it but in the end, from a money saving view, rejected it. I'd fold a couple of strips of baking paper in half and place the sausage rolls in the folded ends. Lower them into the toaster and in 3 minutes I'd have reheated, non soggy sausage rolls.

That's an interesting idea, I might have to try that. Will have to make sure I have the right kind of paper though!

Alnat1

Don't try it if they are raw pastry/sausage meat though, only works for reheating.

matelodave

I'd struggle to get a sausage roll into the bread slot of our toaster unless I squashed it flat.

Not even sure a Ginsters steak Slice would fit - I might have to try it.

Alnat1

Oh, what have I started lol. Think toaster pockets, works same as that really.

Please, no blaming me if anyone's toaster explodes.

Screwdriva

I've been able to measure the A++ oven's draw which is similar to the previous unit.

That said, total power consumption is down considerably as the oven cuts out much quicker, once set temperature has been reached, and the time before reactivation of the heating element has substantially increased. This is particularly beneficial for longer cook times on the "fan" setting. 

Estimated savings are ~30%!!

Exiled_Tyke

Screwdriva said:

I've been able to measure the A++ oven's draw which is similar to the previous unit.

That said, total power consumption is down considerably as the oven cuts out much quicker, once set temperature has been reached, and the time before reactivation of the heating element has substantially increased. This is particularly beneficial for longer cook times on the "fan" setting. 

Estimated savings are ~30%!!

I don't have hard facts but do have a similar experience. I had an old NEFF oven which wasn't very well insultated (or actually any good). Last year I got a modern one. NEFF again and pretty effecient (according to Which?) I immediately noticed the difference.  A new problem for me is that any cooking instructions that suggst starting at a high temperature and then lowering it can't be followed as the oven doesn't cool down quickly enough and things tend to overcook!

Screwdriva

Exiled_Tyke said:

I don't have hard facts but do have a similar experience.

Good to know. I imagine this benefit will be amplified for battery owners!

Screwdriva

Just replaced our dishwasher with a German made A rated Siemens unit.

The old Bosch consumed 1.02 kWh per cycle, the new Siemens unit is 540 Watts per cycle. Quite incredible to see a near 50% improvement in energy consumption achieved in the last half decade!