Slow cooker.

[windywillow]

Which would be more energy-efficient - using a slow cooker for 8 hours on low setting or 4 hours on high setting? Or would it cost about the same?

TIA.

[Rollo]

It depends on the power cvonsumption for each of the settings.

Read the manual book.

[windywillow]

Thanks for reply. Unfortunately I can't find the manual.

[Rollo]

Google the model you have. You will probably find the manual online.

[buildersmate]

Whilst understanding where Rollo is coming from, I don't think that is right. The answer is that the low setting uses less power in total.

Rollo's answer would be true of a space heater that is 'on' all the time, pumping heat out into the air around it.
However the purpose of slow cooker is a raise the temperature of the innerds to a certain temperature, then hold it constant at that temperature for a number of hours.
At the low setting, the cooker thermostat holds it at a lower temperature than on the high setting, and the meat only cooks at that low setting because it is held there for longer.
Once the selected temperature is reached, the cooker only pumps more heat in to replace heat losses to the surrounding air - much of the time the thermostat is switched 'off' and no power is consumed. To this extent it works the same way as a domestic iron.

For reasons of physics I won't try and explain, the heat loss to the outside is much greater when the temperature differential (cooker setting temperature to ambient air temperature in the kitchen) is greater. It is so much greater that it will more than 'cancel out' the extra time (8 hrs, not 4hrs) that the cooker on the lower setting spends 'on'.

[windywillow]

Thanks very much buildersmate. Very kind of you to take the trouble to type all that. 8 hours on low it is then!

Thanks to you too, Rollo. xx