Most energy efficient way of bringing water to the boil for cooking pasta?

Question

Do I put cold water in a pan on the gas hob? Or do I boil water in the electric kettle first and then move the water to the hob?

Which one uses the least energy???

I need evidence please... as I'm arguing with a wannabe Environmental Management Officer

Thanks

Answer 1

I guess if you really want to save energy put the pasta in the pan as the water heats up.  Not sure if that'll affect the quality of the pasta though.

Answer 2

Not totally sure but i think a kettle is a very expensive, but quicker way of heating water. Thats why central heating boilers are usually gas and electric showers cost a fortune to run

To tell, turn all the appliances of in your house. Heat 1 kettle and 1 gas powered pan of water and watch the 2 meters move. Your bills will have the cost per unit so all you need is a bit of maths.

Have a pint on the result.

Answer 3

A solar cooker is the most efficient way by far. this is cheap and energy efficient to manufacture, and it uses the sun to cook with. Used alot in places like the Gobi desert where any type of fuel is scarce. Of course, no sun, no cooked pasta!

Answer 4

If you boil anything in a pan remember to put the lid on,or it will take far longer to boil.

Answer 5

Not quite the answer you're looking for BUT...

Microwave is fastest and uses less power and water, so less condensation too. Use 1 pint of boiling water to 8oz pasta in a large bowl (mines a large mixing bowl) use pasta shapes, obviously spaghetti won't work unless you've an industrial sized micro... Cover the bowl with cling film and pierce once in the centre.

In the micro for 7-10 mins for 'white' or 12 mins for wholemeal on HIGH.

Drain in colander and there you go.

Been doing it for years.

Answer 6

heat can be wasted on the hob, but in a kettle, all the heat dispenses to the water, which is why it is quicker.

Answer 7

I think boiling the water in an electric kettle as the heat is contained.  A lot of heat is wasted using gas.

A more efficient way is to use a microwave.

Answer 8

I'd go for the kettle, if only because electricity can be generated from renewable sources. Gas is non-renewable.

Answer 9

I must admit.....I boil a kettle!!

Answer 10

Gas wins hands down.  Most electricity is produced in thermal power plants that operate at 30-40% efficiency.  If you boil water in an electric kettle, a power plant burns gas to generate electricity and 60% (or more) of the heat is wasted.  The remaining 40% is converted to electricity, transmitted down the line (another loss of 1-5%), then converted back into heat by the kettle.  Bottom line is that boiling water with an electric kettle will burn at least 3 times as much gas as would boiling it on a gas stove.

As a general rule, electricity is the least efficient way to produce heat which is why electricity is the most expensive way to heat a house.

Answer 11

the quickest way to boil water is to use water that has already been boiled, even if it has cooled.  (the reason gets into some seriously complex physics).  But to boil water on a stove, pour half into the pot or kettle you wish to use.  Boil the other half in a microwave oven.  the microwave water will boil quickly but it's hard to get the right temperature.  Once the microwave water boils, pour it into the kettle or pot.  (Be careful and use a protective pot holder or mitt)

Answer 12

I've always boiled the kettle first as that is much quicker than waiting for cold water to warm up on a gas hob.  And I think electricity is currently cheaper than gas.  The better option would be to cook the pasta in the microwave.

Answer 13

As has been mentioned the electric kettle is very efficient at converting electrical energy to heat in the water. But as has also been pointed out, to produce the electricity in the first place is costly in terms of energy. So overall efficiency from source energy to final heat is quite low. If the electricity has been produced by a fossil fuel fired power station this is a very bad idea. If it has been produced from renewable resources then less of a bad idea but still expensive.

Not all gas cookers are equal in efficiency and not all pots n kettles either. A good gas kettle combination can collect most of the heat from the stove. Making this quite efficient.

Better still instal solar hot water and use the hot water heated free by the sun to start with. Saves time and cost and energy.

As has been said already put a lid on the pan, saves lots of energy.

Microwaves are not as efficient as they seem. You need to take both the time and wattage into account. Check out just how much energy your microwave is using. Not just its rated output! Electric kettle is more efficient than a microwave hands down! The microwave may be faster because it is using more electricity, that is not energy efficiency.  Besides what has been said about electricity before applies to the microwave as well.

It takes 4.2 joules of energy to heat one gram of water one degree. Heating most other things like metals, air, ceramic takes a LOT less energy. Evaporating a gram of water takes a huge amount of energy 2000+ joules, so put the lid on to avoid evaporation!

By the way the gas could in theory be renewable if it came from a bio digester or rubbish dump.

Overall the question needs to be refined to really get an answer, as it is a bit vague. Is it the amount of CO2 produced over all that is at issue, or strictly the efficiency of the appliance in question regardless of where the source energy is coming from?

Answer 14

Gas hob is the best way to go if you are trying to impress an environmental management officer. If you cite the fact that during the commercial break after a hit tv programme like Friends of House or something, The national grid is put under huge demand as people rush to put on the kettle. The physics behind it are also worth considering. Dont boil the water without a lid and never add the salt until the water has boiled. Salt water boils significantly slower than unsalted.

Answer 15

The electric kettle is actually the most efficient device in the home - as it has no unwanted byproduct and almost all the heat goes directly to heating the water.

When you think about all the space around a gas hob that is also being heated, it is easy to see why.

Answer 16

The amount of energy it takes to boil water is the same so it really depends on how efficiently the energy is used in the electric kettle vs. gas hob.