Regarding the Feb. 10 test, I pooh-poohed the notion that the cell was
actually producing 4 kW, raising the water temperature 1 deg C, and the
other 3 dec C came from some path other than the water, for example by
conduction through the body of the machine to the outlet thermocouple.
To be sure, McKubre and others have pointed out that the outlet thermocouple
position is not ideal, and it might be picking up some heat from another
path. This may be happening to some extent. It might even be measurable. But
it can be shown that other paths are minor compared to the flow of water.
It is certain that the inside of the cell is considerably hotter than 100
deg C. You could not heat water or make steam if the inside were barely
above boiling temperature. If there is a significant heat path, it will
conduct temperatures well above 100 deg C. Take a boiling pot of water. The
sides of the pot above the water level will be much hotter than 100 deg C.
So, if there was a lot of heat being conducted to the outlet thermocouple,
that thermocouple would not have settled at boiling temperature just
above 100 deg C. It would have gone measurably well above that. Steam does
not conduct heat as well as water does. Furthermore, 0.3 L of water per
minute does not conduct anywhere near as much heat as 60 L per minute. That
is a large flow of water.
Even supposing the steam was quite wet, the mixture of steam and water would
still have been close to 100 deg C. Water goes right up to the phase
transition temperature before there is any steam at all. It would not have
been, let us say, 80 deg C, with the extra 20 deg C sneaking in from
conduction or radiation directly from the cell to that thermocouple
location. At 80 deg C there would have been no indication of steam -- no
sound, no bubbles at the end of the pipe -- nothing.