Which is the most energy efficient ?

Page may contain affiliate links. Please see terms for details.

snailracer

Über Member
Regarding why a microwave is more energy efficient.

A 3000W kettle takes around 2.5 minutes to boil a litre of water. That's 0.125 kWh energy consumption.
A 1000W microwave takes around 7 minutes to cook potatoes. That's 0.117 kWh.

Even without counting the energy required by a gas or electric hob to cook the potatoes, the microwave is more energy efficient.
So is 1000W the rating labelled on the front, or the power consumption labelled on the back of your microwave?
 

subaqua

What’s the point
Location
Leytonstone
I use the kettle, but just before it finishes I put a small amount of water in the pan and heat that up, so I don't end up putting the boiling water straight into a cold pan.

There's no fear of underestimating the energy used by my kettle - the lights in the kitchen dim whenever it's on.

would get the main switch on the Consumer unit checked for a loose connection. I would also suggest that after that has been checked and it is found to be oK calling whoever the DNO is in liverpool these days ( used to be MANWEB when i lived up that way) and getting them to check the terminations in the service head( cut out). my kitchen lights used to dim a bit when i put the shower on , when i changed the Consumer unit for a new one I checked the inside of the cut out fuse ( seals were missing ) and it was arcing badly at the phase connection as the incoming cable term was loose.


as for the OP , there is so little difference as to be negligible due to the heat losses in the transfer to cold pan from hot kettle. i.e. any saving made with the direct contact of the kettle element to the water will be lost by having to heat the pan from cold.
 
U

User482

Guest
So is 1000W the rating labelled on the front, or the power consumption labelled on the back of your microwave?
good point. Google suggests a 1000w microwave uses around 1500w on full power. that's still far more efficient than kettle plus hob.
 
good point. Google suggests a 1000w microwave uses around 1500w on full power. that's still far more efficient than kettle plus hob.
So what's the wattage on the front used for then?? I was a bit freaked out when our (now deceased) microwave was pulling more than its stated wattage consistently (we bought a plug that monitors electricity usage)
 
U

User482

Guest
So what's the wattage on the front used for then?? I was a bit freaked out when our (now deceased) microwave was pulling more than its stated wattage consistently (we bought a plug that monitors electricity usage)
That's the cooking power, which allows you to use standardised recipes. It's less because energy is lost converting electricity into microwaves.
 

Kestevan

Last of the Summer Winos
Location
Holmfirth.
Buy a pressure cooker. In the time it takes to bring a full pan of water to boil your food will be cooked.
Increased pressure ups the boiling point to 125C and the super-heated steam cooks the food really well.
Cooks spuds in 10 minutes, brown rice takes not much longer.

Best kitcheny thing we ever bought.
 

snailracer

Über Member
good point. Google suggests a 1000w microwave uses around 1500w on full power. that's still far more efficient than kettle plus hob.
The kettle would therefore be a more efficient way of heating the water to boiling point, but how much additional energy is needed to simmer the potatoes in the pan is a bit harder to quantify.
 

rich p

ridiculous old lush
Location
Brighton
I've cooked bacon in a microwave before for some unfathomable reason. Maybe the cooker was fecked.

It doesn't crisp up but it was incredibly tasty.
 

Archie_tect

De Skieven Architek... aka Penfold + Horace
Location
Northumberland
Had a college friend who cooked a white puddin' in a slow-cooker all day ready for his tea to save electricity.

The margin for error, overboiling spuds in a microwave, is very small.
 
U

User482

Guest
The kettle would therefore be a more efficient way of heating the water to boiling point, but how much additional energy is needed to simmer the potatoes in the pan is a bit harder to quantify.

The microwave is cooking the potatoes whereas the kettle is just boiling water.

You could make a stab at calculating the energy to simmer the spuds. Assume a 1.5kW electric hob runs at half power for 15 minutes. That's 0.187 kWh.

Roughly, a microwave will use half the energy of a kettle and pan.
 
Top Bottom