Induction hob

[Bugtownboy]

Not all Stainless Steel is magnetic - as you’ve found out.

The defining factor of magnetism comes down to the the steel's microstructure. Martensitic stainless steels (which have a ferritic microstructure) are magnetic. Austenitic stainless steels contain nickel and are non-magnetic

[openspaceman]

Similar deal as Joeboy, 500ml of cold tap water heating test.

Gas hob, pan 3/4 full on medium size burner – 6 min 10 sec, 0.019m3 gas or 0.21 kWh
Same pan on 2kW induction hob – 5 min 20 sec, 0.18 kWh
Full glass jug 1.6kW microwave – 5 min 10 secs, 0.14 kWh
2kW glass kettle – 1 min 50 secs, 0.061 kWh

Replying to a year old post but have just read through the thread.

That figure for gas is comparatively good if using fossil fuel generated electricity

Using Oliver90owner's 0.05kWh to heat water from 10C to boiling (which I agree with) that means overall efficiency:

Gas 0.21kWh 23.81%
Induction hob 0.18kWh 27.78%
microwave 0.14kWh 35.71%
Kettle 0.061kWh 81.97%

Obviously neglecting issues about heat lost to pans and atmosphere.

It justifies my wife's habit of boiling water in a kettle before adding to the pan with veg in.

The gas figure would improve with a skirt and small <10mm air gap I expect as we see a doubling of heat transfer efficiency with a skirt on wood fired stoves.

I am not at all surprised about the poorer performance of the microwave but was surprised about the induction hob which I wonder might be to do with the mass of the pan??

I too have changed to a 2kW kettle and a 2.4kW air frier in order to cut electricity use. The latter is is used for everything except for large meals as it is quick and low mass compared with our conventional oven.

I have a stand alone induction hob but the granularity of the control is too coarse with only nine power levels so have not replaced the ceramic hob yet.

[Joeboy]

Similar deal as Joeboy, 500ml of cold tap water heating test.

Gas hob, pan 3/4 full on medium size burner – 6 min 10 sec, 0.019m3 gas or 0.21 kWh
Same pan on 2kW induction hob – 5 min 20 sec, 0.18 kWh
Full glass jug 1.6kW microwave – 5 min 10 secs, 0.14 kWh
2kW glass kettle – 1 min 50 secs, 0.061 kWh

Replying to a year old post but have just read through the thread.

That figure for gas is comparatively good if using fossil fuel generated electricity

Using Oliver90owner's 0.05kWh to heat water from 10C to boiling (which I agree with) that means overall efficiency:

Gas 0.21kWh 23.81%
Induction hob 0.18kWh 27.78%
microwave 0.14kWh 35.71%
Kettle 0.061kWh 81.97%

Obviously neglecting issues about heat lost to pans and atmosphere.

It justifies my wife's habit of boiling water in a kettle before adding to the pan with veg in.

The gas figure would improve with a skirt and small <10mm air gap I expect as we see a doubling of heat transfer efficiency with a skirt on wood fired stoves.

I am not at all surprised about the poorer performance of the microwave but was surprised about the induction hob which I wonder might be to do with the mass of the pan??

I too have changed to a 2kW kettle and a 2.4kW air frier in order to cut electricity use. The latter is is used for everything except for large meals as it is quick and low mass compared with our conventional oven.

I have a stand alone induction hob but the granularity of the control is too coarse with only nine power levels so have not replaced the ceramic hob yet.

In my limited time of use of both induction hob and airfryer I have been taken with their efficiency, speed of cooking and relaxing feel of use. The airfryer in particular has also improved the quality of end product. Today I am parboiling potatoes on the induction hob before airfrying them as roasters later on. All saved power will find its way to the EV I'm sure.
Olive oil and homegrown chilli flake shake

[nowty]

Similar deal as Joeboy, 500ml of cold tap water heating test.

Gas hob, pan 3/4 full on medium size burner – 6 min 10 sec, 0.019m3 gas or 0.21 kWh
Same pan on 2kW induction hob – 5 min 20 sec, 0.18 kWh
Full glass jug 1.6kW microwave – 5 min 10 secs, 0.14 kWh
2kW glass kettle – 1 min 50 secs, 0.061 kWh

Replying to a year old post but have just read through the thread.

That figure for gas is comparatively good if using fossil fuel generated electricity

Using Oliver90owner's 0.05kWh to heat water from 10C to boiling (which I agree with) that means overall efficiency:

Gas 0.21kWh 23.81%
Induction hob 0.18kWh 27.78%
microwave 0.14kWh 35.71%
Kettle 0.061kWh 81.97%

Obviously neglecting issues about heat lost to pans and atmosphere.

It justifies my wife's habit of boiling water in a kettle before adding to the pan with veg in.

The gas figure would improve with a skirt and small <10mm air gap I expect as we see a doubling of heat transfer efficiency with a skirt on wood fired stoves.

I am not at all surprised about the poorer performance of the microwave but was surprised about the induction hob which I wonder might be to do with the mass of the pan??

I too have changed to a 2kW kettle and a 2.4kW air frier in order to cut electricity use. The latter is is used for everything except for large meals as it is quick and low mass compared with our conventional oven.

I have a stand alone induction hob but the granularity of the control is too coarse with only nine power levels so have not replaced the ceramic hob yet.

Just to say I f’d up the induction figure. Although the hob is rated at 2000w, probably because of the small size of the pan it was only using about 1000w because I looked back at my post it note I had written the power levels on. So in fact the induction hob was only 0.09 kWh so better than the microwave and not far away from the kettle.

Also not far away from Joeboys result.

[Joeboy]

As an aside, I ran up the airfryer tonight 20mins 200degs and it used 1.07kWh. Same temp and time as yesterday yet more food cooked. Reflected in the power consumption.

12 haggis bites
8 sausages
Roast potatoes for 3 people.

I agree on the kettle efficiency, then induction, then air fryer with fan assisted cooker following and gas last? I didn't measure microwave.

No doubt this double whammy of cooking improvements will show up on the home consumption chart at end of the year. They feel like quite a big deal in that regard. Bombed out the gas a while back and let's now maximise the benefits from electricity used.
I feel sorry for the average grid user, I enjoy the heightened awareness.

[billi]

Great day to cook outside today after sunset

[Bugtownboy]

Way to go

[openspaceman]

Just to say I f’d up the induction figure. Although the hob is rated at 2000w, probably because of the small size of the pan it was only using about 1000w because I looked back at my post it note I had written the power levels on. So in fact the induction hob was only 0.09 kWh so better than the microwave and not far away from the kettle.

Also not far away from Joeboys result.

Ah so you were calculating the figure from rated power of the induction hob time the time it took?

[nowty]

Just to say I f’d up the induction figure. Although the hob is rated at 2000w, probably because of the small size of the pan it was only using about 1000w because I looked back at my post it note I had written the power levels on. So in fact the induction hob was only 0.09 kWh so better than the microwave and not far away from the kettle.

Also not far away from Joeboys result.

Ah so you were calculating the figure from rated power of the induction hob time the time it took?

Sort of, I got my maths wrong on a simple subtraction calculation and thought it was 2000w which happened to match the badged power consumption and as I had it on full power it reinforced my result. Should have re-ran the experiment with it being so out compared with Joeboys experiment. But as I had the raw data on a post it note which was still stuck to my desk a week later I realised my subtraction error so don’t need to re-run the experiment.

[Mr Gus]

For the brave amongst you.

https://www.wellplated.com/air-fryer-brussels-sprouts/

NB, anyone else looking at an airfryer right now there is a 20% off code on amazon currently, so for instance the linked 5.7 litre unit is reduced to £95.99 from £119.99 when applied at checkout

https://www.amazon.co.uk/Instant-Pot-Vo ... 1HQ87?th=1

Discount also applicable to the dual air fryer too.