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by SilverRed 1762 days ago
Not always using a clothes dryer is fine and good advice. But not using an electric kettle and replacing it with heating water on a gas stove is so beyond absurd I'm shocked how they even came to this conclusion since gas stoves are less efficient and much worse for the environment than a kettle.

And a kettle is so low impact anyway. It uses a high amount of power for a very short time and spends almost all of its life turned off. The faster you heat the water the less waste there is as it cools during the heat process.

2 comments

> since gas stoves are less efficient and much worse for the environment than a kettle.

It is not obvious at all and requires calculations.

When you use electric kettle you use energy which was obtained mostly from coal and gas (60% of it in the US) and efficiency of the conversion is less than about 40% on average (limited by efficiency of a steam turbine). Then about 8% of this power is lost during transportation/distribution.

When gas is burned in a gas stove 100% of its energy converted to heat. The only problem - some fraction of this energy heats a room instead of a kettle. But it is not bad if you had to heat room anyway (where I live 8-10 months out of 12 I'd prefer indoor temperature to be higher then it is).

I expect this loss to be smaller than 50%, but I've not found credible numbers for this.

Efficiency for an oven may be low because it measurably heats a kitchen, but ovens is another story.

>It is not obvious at all and requires calculations.

Heating water in a domestic setting on a gas stove is incredibly inefficient and you don't even need a calculator to know why - put your hand adjacent to the stove and feel the heat being lost. This is not a small fraction, it is significant unless you run the stove really low and spread that heat over a large area.

Now put your hand and any point outside an electric kettle and see how much heat you can feel. Almost none.

This isn't really as complicated as you're making it out to be.

Thermal loss of course bigger for kettle on a gas stove than for an electric kettle. But while electricity is generated on a gas/coal powered plan a lot of heat emitted into the environment, and we cannot ignore this if we are interested in overall efficiency.
This has been studied a fair amount, from memory gas is in the low to mid 40% range, induction & immersed coil are in the mid 80% range.

Gas stove is nominally competitive, but as soon as you start adding renewables to the power mix or considering indoor air quality & venting, electric seems like the path forward to me.

It should be possible to just heat the 1l of water in a kettle and in a pot using gas, and compare the electricity and gas consumed.

Time-wise I'd think it's quite comparable, in my experience.

This of course depends on sizes and quality of kettle/pot. Wide pot, with large surface area and a quality heatspreader on the bottom will get the water boiling more quickly. Also covering a pot is a must.

Sometimes when I'm in a hurry I split the water between a pot and el. kettle, to get a boiling 2l of water faster, and there's no huge difference in time to boil.

Have you tried induction stove? It loses almost no heat to outside of pot and that makes palpable difference.
An induction stove is pretty much the same thing as a kettle for heating water. The OP post is against kettles because they require AC power which their solar panel and battery can not sustain.

But somehow gas doesn't have to be accounted for and just comes for free.

But in this conversations its basically an electric kettle.
Well, if you burn wood to boil water, it's a renewable, right? I am sure we can use wooden stoves for cooking.

Besides, why you need to boil water for tea or coffee? These days tap water is safe for drink, and if you want to add extra flavor, you can chew your tea leaves or coffee beans... ;-)