Gas-hob kettle or electric kettle?
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- emordnilap
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Nice answer, SS.
Of course, in winter if you have a suitable wood stove burning, sticking a gas hob kettle on it in anticipation of making a cuppa makes sense. It only needs 'finishing'.
We usually have a second kettle chuntering away on the wood stove for doing the dishes or whatever; this is used first and then re-filled with the 'deadleg' cold from the hot tap; it's not used for human consumption as the water has been softened with salt.
Some casually browsing the forum might think threads such as these are pernickety, especially those who simply flick switches. The real point to me is the thinking about things that most people take for granted, as well as making energy conservation and efficiency a habit.
Of course, in winter if you have a suitable wood stove burning, sticking a gas hob kettle on it in anticipation of making a cuppa makes sense. It only needs 'finishing'.
We usually have a second kettle chuntering away on the wood stove for doing the dishes or whatever; this is used first and then re-filled with the 'deadleg' cold from the hot tap; it's not used for human consumption as the water has been softened with salt.
Some casually browsing the forum might think threads such as these are pernickety, especially those who simply flick switches. The real point to me is the thinking about things that most people take for granted, as well as making energy conservation and efficiency a habit.
I experience pleasure and pains, and pursue goals in service of them, so I cannot reasonably deny the right of other sentient agents to do the same - Steven Pinker
- adam2
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And BTW dont be tempted to buy a "low consumption" electric kettle in order to reduce energy used !
Most standard electric kettles are about 2.4 to 3.1 KW, but lower loading ones are available. These take longer to boil and will actually use very slightly more energy to boil a given volume of water. (because they take longer to boil, heat is being lost for longer)
The only sensible use of a low loading electric kettle is when only a limited electricity supply is available, such as from a lighting socket, or at a camp ground or marina that supplies "free" electricity but only up to 5 or 6 amps.
If you can be bothered, a kettle can eventually be boiled over a Tilley lamp, or other large oil lamp.
Most standard electric kettles are about 2.4 to 3.1 KW, but lower loading ones are available. These take longer to boil and will actually use very slightly more energy to boil a given volume of water. (because they take longer to boil, heat is being lost for longer)
The only sensible use of a low loading electric kettle is when only a limited electricity supply is available, such as from a lighting socket, or at a camp ground or marina that supplies "free" electricity but only up to 5 or 6 amps.
If you can be bothered, a kettle can eventually be boiled over a Tilley lamp, or other large oil lamp.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
-
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@emordnilap Thank You for the compliment I always keep in mind that God is in the details (apparently). Better to get the right answer as the best is rarely the most common.
@adam2 Your timing is perfect, a friend has just asked about this very thing! Will give her a call now. Thanks
@adam2 Your timing is perfect, a friend has just asked about this very thing! Will give her a call now. Thanks
Scarcity is the new black
-
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Best not to forget the Total Cost of Ownership.
I've had my hob top kettle for well over a decade and before that I was getting through an electric kettle about once a year.
I'm blessed with soft water here but if you live in a hard water area then your electric heating element will soon become caked and therefore less efficient.
I've had my hob top kettle for well over a decade and before that I was getting through an electric kettle about once a year.
I'm blessed with soft water here but if you live in a hard water area then your electric heating element will soon become caked and therefore less efficient.
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Not so. We live in a hard water area, and at one time we did used to get thick scale deposits on the element. But for the last 30 years or more when there was some change in the chemicals added to the water, kettles no longer got furred up.
We don't use an electric kettle much now, as with a woodburner, a kettle is always on it when it's lit.
We don't use an electric kettle much now, as with a woodburner, a kettle is always on it when it's lit.
- woodpecker
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It's probably a corollary of Brooks's Law:
http://en.wikipedia.org/wiki/Brooks%27_law
A corollary of Einasto's Law indicates that the size of the fish will be directly proportional to the square of the distance between the kettle and the fishing rod.
http://en.wikipedia.org/wiki/Brooks%27_law
A corollary of Einasto's Law indicates that the size of the fish will be directly proportional to the square of the distance between the kettle and the fishing rod.
gas or electric kettle cheaper?
Interesting topic and I think some claims are somewhat exaggerated, like that a electric kettle is 100% efficient (meaning no resistance or heat loss & no residual heat in element & kettle body after heating)
Personally I would assume an electric kettle at 80% at best.
Gas Hob to Hob kettle maybe less efficient in heating water, but you can be sure that most of the energy was turned to heat, which is all useful if room heating is required.
Some have compared with pan's on the hob, which are not as efficient as a hob kettle, so I've done some measurements myself using a standard thick based copper hob kettle against a standard flat based but uninsulated 2.2 kW electric kettle boiling 500ml of water from cold.
Gas took 5 mins on full (standard burner) equates to 0.171 kWh = 0.615p
Electric took 1min 50 sec equates to 0.067 kWh = 0.781p
So gas used 155% more energy but cost 27% less.
These figures with electric costing 3.24 times gas cost per kWh
Gas/energy conversion: stove-top gas burner = 7000 BTU/hr
Using the conversion P(W) = P(BTU/hr) / 3.412142 : 583.3 BTU = 171 W
Based on this I`ll stick to gas unless I`m in a hurry.
PS for the CO2 watchers out there electric is 36g CO2 and gas 32.5g C02, so gas best again.
Personally I would assume an electric kettle at 80% at best.
Gas Hob to Hob kettle maybe less efficient in heating water, but you can be sure that most of the energy was turned to heat, which is all useful if room heating is required.
Some have compared with pan's on the hob, which are not as efficient as a hob kettle, so I've done some measurements myself using a standard thick based copper hob kettle against a standard flat based but uninsulated 2.2 kW electric kettle boiling 500ml of water from cold.
Gas took 5 mins on full (standard burner) equates to 0.171 kWh = 0.615p
Electric took 1min 50 sec equates to 0.067 kWh = 0.781p
So gas used 155% more energy but cost 27% less.
These figures with electric costing 3.24 times gas cost per kWh
Gas/energy conversion: stove-top gas burner = 7000 BTU/hr
Using the conversion P(W) = P(BTU/hr) / 3.412142 : 583.3 BTU = 171 W
Based on this I`ll stick to gas unless I`m in a hurry.
PS for the CO2 watchers out there electric is 36g CO2 and gas 32.5g C02, so gas best again.
Using Ubuntu Linux with virus worries a thing of the past!
- careful_eugene
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- adam2
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Not certain that I could recomend a kettle on an induction hob.
Induction hobs are excellent for general cooking and much more efficient than a traditional electric hob.
Also very controllable and permit of butter or chocolate being melted without use of a water bath.
For boiling water though, I would expect an electric kettle to be more efficient. It would be diffecult to beat a heating element immersed in the water with almost no losses.
The electronics in an induction hob do have some losses that wont occur with an electric kettle.
Electric kettles do break, but so do induction hobs, and the kettle is a lot cheaper to replace.
Induction hobs are excellent for general cooking and much more efficient than a traditional electric hob.
Also very controllable and permit of butter or chocolate being melted without use of a water bath.
For boiling water though, I would expect an electric kettle to be more efficient. It would be diffecult to beat a heating element immersed in the water with almost no losses.
The electronics in an induction hob do have some losses that wont occur with an electric kettle.
Electric kettles do break, but so do induction hobs, and the kettle is a lot cheaper to replace.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
I'm surprised by the number of people who have problems with their electric kettles, I often hear of people who get through kettles on an annual basis. This seems daft, as boiling water with electricity should be something we can archive with ~100% reliability. I'm sure in many industrial processes, electrical elements manage to boil water for years reliably.
- adam2
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Cheap water heating elements used industrialy fail regularly, I replace perhaps a dozen a year in a small office building.
Better qaulity water heating elements sheathed with special alloys last for many years.
Electric kettles are very cheap with little thought given to long life.
And it is not allways the element that fails in a cheap kettle.
Overheat cut out becomes too sensitive and trips before the water boils
Electrical connections work loose and melt
Water gets into base of cordless kettle
are common reasons for replacement.
The less well off generaly choose the cheapest kettle from argos or similar stores.
The middle classes choose a fashionable or trendy styled kettle
The upper classes leave it to the staff.
No one cares about long life.
Better qaulity water heating elements sheathed with special alloys last for many years.
Electric kettles are very cheap with little thought given to long life.
And it is not allways the element that fails in a cheap kettle.
Overheat cut out becomes too sensitive and trips before the water boils
Electrical connections work loose and melt
Water gets into base of cordless kettle
are common reasons for replacement.
The less well off generaly choose the cheapest kettle from argos or similar stores.
The middle classes choose a fashionable or trendy styled kettle
The upper classes leave it to the staff.
No one cares about long life.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
I care about long life, but it is impossible to buy a long life electric kettle. The cost of building and marketing a kettle with a guaranteed life of 5+ years exceeds the expected market returns so nobody does it. The public, if they think about it at all, are so cynical about consumer product guarntees that they mentally discount them anyway.
We recently bought a new kettle because ours die so regularly we decided to have one in reserve. Price has never shown any correlation with reliability.
Since becoming energy aware we now avoid the more high powered kettle elements. Not that there is any energy saving in use, but because it would reduce the peak load on any off-grid electricity supply. (Actually we would use our hob kettle or the wood burner in that instance).
We recently bought a new kettle because ours die so regularly we decided to have one in reserve. Price has never shown any correlation with reliability.
Since becoming energy aware we now avoid the more high powered kettle elements. Not that there is any energy saving in use, but because it would reduce the peak load on any off-grid electricity supply. (Actually we would use our hob kettle or the wood burner in that instance).