The rules for both methods were that we would start with
water from the cold tap,
and the goal was to end up with a pan full of boiling water.
I started with the gas method.
Experiment 1
I measured the energy consumption of the gas method
by
pouring one litre of water in the pan,
reading
the meter, then setting the gas going.
I put a lid on the saucepan.
The first four digits on the meter give the gas used in hundreds of
cubic feet;
the next two (red) digits give cubic feet, and the dial reads the
fraction of a cubic foot.
The initial reading was 515316.18 cubic feet.
The heat of the flame was amazing, but the kettle-advocates clearly
had a point, when they say that the gas method is inefficient:
hot exhaust gases surged up the side of the pan.
After about 5 minutes, the water was boiling.
I read the gas meter again. The new reading was
515317.10 cubic feet.
Now, each cubic foot has a chemical energy of 0.3232 kWh.
So, subtracting and multiplying appropriately,
the energy used by the gas method turned out to be
0.3 kWh
Continue reading part 2 of How much is inside hot water...
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