As it happens - my glamorous research buttistant was busy, so I resorted to computers.
I have been trying to track down why my electricity bill is 50% higher than my gas bill even though the house is heated by gas. To achieve this I have built an electricity monitor. I measure the amps going to my distribution panel and store this in a database for analysis.
So - I took a mug (250ml) of water at 14 degrees C, and put it in the 900W microwave for 2 mins 15 seconds. The water temperature was 90degrees C (and the mug was hot)
I took the same amount of water and put it in the kettle. After 53 seconds the kettle boiled. I poured the water into a cold mug, and the temperature was 87 degrees C.
The current consumed by the microwave for 2 mins 15 seconds was 6 A. The current consumed by the kettle for 53 seconds was 12A.
If my calculations are correct, the cost of heating a mug of water in the kettle (at 7.9p-kWh) is .33p The cost of heating the mug of water in the microwave is .42p.
Lyndon
