Electric Kettle or Gas Saucepan Cheapest Use?

[T Bently]

I got to wondering whether it was cheaper to use gas or electric to make our cups of tea.

So I sent this request to the technical department of my utility supply company.

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Would you kindly be able to advise me from my account details above, and bearing in mind that i take both my gas and electricity supplies from you, please.

Which would use less energy and therefore be cheaper for me to bring to the boil, a litre of water; using [1] an *electric* kettle or [2] heating over the *gas* hob in a saucepan (with the lid on) ?

----------------------------------------------------------------------------------------------------------------------------------------------------- They sent this email in reply:

I would like to inform you that cheaper energy costs depends on the power of the appliance you are using and the amount of time your are using it for. Then you can have an idea as to how much energy you have used and then the costs can be calculated and compared. It will also depend on whether you are on the cheapest plan as per your consumption patterns or not.

To ascertain which plan would be cheapest for you, we would need to create a quotation based on your actual consumption pattern.

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I dont feel i'm further ahead. Is it at all possible for them to reasonably say which is the cheapest way to boil a litre of water by gas or electric ? Since they have all my tariff details with them and account number, etc.

[Mentalguy2k8]

I think they're politely telling you it's impossible for them to know and to go and find out for yourself.....

They can only tell you how many pence per unit of each energy they're charging you, they don't know what kettle you've got, how long it takes to boil, the dimensions of the saucepan and whether it has a lid, how much gas gets used by your particular cooker to boil X amount of liquid, the ambient temperature of your kitchen etc.

The only accurate way would be to turn everything in the house off, take gas and electric meter readings and then boil one litre of water in the kettle, take another electric reading, then boil one litre of water in a pan and take the new gas reading. Then subtract the old readings from the new, and there's your consumption (in units or part units) for each type of energy. Multiply those by the relevant unit prices, and you should have an answer.

[Andy Burns]

But they don't know any details of your kettle, hob, or saucepan.

The starting point in both cases, is to only boil the amount you require.

For an electric kettle, almost all the heat is released direct into the water, but the cost per unit will be approx 3x higher. With the gas some heat will be lost up the sides of the pan, less so with a larger pan, but then you've got to heat a larger lump of metal as well as the water.

Do any storm kettles fit over gas rings?

[meow2222]

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The amount of water you boil is irrelevant, as long as its the same in both cases. The power rating of the kettle is also irrelevant, as long as its w ithin reasonable limits, power x time = energy is very close to the same whatever the power.

What matters is the cost of the 2 energies (the ratio is normally about 3:1 in favour of gas) and the efficiency of the gas heating arrangement. If th e gas setup is over 33%, gas wins, if its under 33% gas loses. To maximise gas pan heating efficiency, use a (cocked) lid & make sure the hot gases ge t as much pan contact as possible. So a small ring tends to be more efficie nt, as it gets more pan contact area, and large high burner settings are le ss efficient as more hot gases rush by the pan without even contacting it.

This isnt something your supplier has any duty to advise you on, nor I dare say any interest beyond appearing to try to be helpful.

NT

[Artic]

Andy Burns scribbled...

Gas kettles usually have a ridge around the bottom, which often has some fancy fluting.

[Artic]

T Bently scribbled...

I bet they have sent a copy of your letter to Jasper Carrot.

[Theo Markettos]

Theo

[Harry Bloomfield]

T Bently used his keyboard to write :

a tricky one to even start to calculate. You would need to actually measure it to get accurate figures.

However assuming your gas is half the cost of your electric, for the same heat value I would suggest electric will be cheaper for the same amount of water heated through the same temperature range. My reasoning is as follows....

Pans and kettles for use on gas are not very good at extracting the heat from a gas flame. An electric kettle is 100% efficient. I would guess a gas kettle might manage 50% or less efficiency in capturing the heat from the flame. Add to that the fact that an electric kettle will switch off when it boils, whereas a gas kettle does not, so more gas may be wasted turning the water to steam. Modern electric jug kettles are even better, in that you can boil a small amount of water and can better judge how much you are boiling, gas has none of that.

You can though buy more efficient gas kettles, fitted with base intended to extract more of the flames heat.

[Dave Plowman (News)]

Find out how much gas your ring on that hob uses. Measure the time taken to boil a given amount of water.

Your supplier has no idea what sort of hob you have, or which ring on it you use.

You'd also have to figure in the costs of washing up the saucepan afterwards.

[R.G. Bargy]

The same number of kWh of energy are needed to be transferred to the water in each case. Given that the price charged for an electric kWh is typically 3 to 4 times that of a gas kWh, the electric kettle would need to be significantly more efficient than the saucepan.

Please state the efficiency of your kettle and of your saucepan, also the exact price you pay for gas kWh and electric kWh.

[Roger Mills]

Boiling one litre isn't going to use enough energy of either kind to enable you to measure it accurately - especially electricity if you have a digital meter which only displays whole kilowatt-hours. [And for gas, you're going to have to know how to convert cubic feet or metres into kWHr - which foxes many people!]

[Dave Plowman (News)]

Pretty well all appliances state how much power they consume. So the total can be easily calculated by that and the time in use.

[mogga]

Kettle to boil it or microwave a mug full?

[Andy Burns]

A link posted earlier showed that to be the less efficient then electric kettle or gas saucepan ...

[Brian Gaff]

Surely the reason this is hard is that they would need to know exactly the efficiency of the gas device and how much waste is going into heating the air.

My guess at current prices is that Electric is best, and probably even better if you can use off peak cheaper units, but then all your cups of tea would have to be at night. grin. Brian

[John Rumm]

See the table here:

[Dave Plowman (News)]

No - as it's not a saucepan.

[harryagain]

The cheapest method is reckoned to be using and electric "jug" and only putting in the amount of water needed. You can put in as little as a couple of ccs.

[Roger Mills]

That's as may be - but I was replying to someone who was suggesting using the gas and electricity meters.

[Roger Mills]

I rest my case! I know plenty of people - present company excepted(!) - who would be totally confused by a table like that.