Boiling water

graby

Boiling water in microwave instead of electric kettle. Saving per year?

graby

Opinions please.

coffeehound

More expensive than an ordinary kettle !

BUFF

depends upon if you are only heating a single cup in a microwave v more in a kettle with a higher minimum level. Otherwise, as per coffehound.

pochase

On average, in order to boil water, it takes:

- 1500W microwave: 1-1.5 min cup (250 ml) of water,

- 700-800W microwave: 2.5-3 min cup (250 ml) of water,

- gas stove: 6-8 min 1 liter (four 250 ml cups) of water,

- electric stove: 8-12 min 1 liter (four 250 ml cups) of water,

- induction cooktop: 5-6 min 1 liter (four 250 ml cups) of water,

- 1500W kettle: ~4 min 1 liter (four 250 ml cups) of water,

- 2500W kettle: 2-3 min 1 liter (four 250 ml cups) of water, etc.

https://www.batteryequivalents.com/how-long-does-it-take-for-water-to-boil.html

Benny2020

Put the kettle in the microwave, i have my microwave in my freezer and now it freezes and cooks.

lohr500

A quick Google suggests that microwaves aren't that efficient. Figures quoted of between 55% and 80%.

So from the example given above, an 800 watt output microwave could well be using 1000 to 1455 watts. I presume there must be heat generated from the magnetron as it creates the microwaves and that heat is expelled through the cooling fan rather than being forced into the oven.

A small kettle capable of heating just enough water for a cupful must surely then be more cost effective, since 100% of the energy is going into the heating element. 
Or am I missing something?

facade

Get a hob kettle. and boil the exact quantity of water you need (weigh it) on the gas hob.

Gas is still about 1/4 the price of electricity, so even if it were only 50% efficient, it would still be half price, but the waste heat warms the house reducing the heating bill anyway.

I used a hob kettle for ages, until I read some clickbait about the myriad life threatening conditions caused by using the gas hob, now I've gone back to electric, but I still weigh out the exact amount of water required.

BUFF

lohr500 said:

A small kettle capable of heating just enough water for a cupful must surely then be more cost effective, since 100% of the energy is going into the heating element. 
Or am I missing something?

No, but a lot of (most?) electric kettles have a minimum level requirement which may be 500ml-1000ml so you could potentially be heating a lot more water than you actually need..

facade said:

Get a hob kettle. and boil the exact quantity of water you need (weigh it) on the gas hob.

I use a graduated jug to measure my 300ml rather than weighing it. Alternatively, one could just fill one's cup & decant that into the kettle.

greyteam1959

Get a one cup water boiler ??

Ultrasonic

BUFF said:

No, but a lot of (most?) electric kettles have a minimum level requirement which may be 500ml-1000ml so you could potentially be heating a lot more water than you actually need.

I use a graduated jug to measure my 300ml rather than weighing it. Alternatively, one could just fill one's cup & decant that into the kettle.

I do exactly the same with a measuring jug  .

I wonder what proportion of kettles in use today don't allow people to boil so little. The defining difference is I think whether a kettle has a flat bottom or a exposed coiled heating element - the latter needs to be covered with water and so sets a minimum fill level.