If considered that in E-Cat there is constantly flowing cool water to replenish boiled water, then it is quite obvious that 2.5 kilowatt is very much possible with Mats' E-Cat. However Steven's E-Cat was malfunctioning while video was shot.
That stove was quite modern, therefore it is likely that around 90% of heat goes for boiling water, because it is good idea to design stoves that produces as little as possible waste heat. However it would have been a good idea to measure weight of the pot before and after the experiment. This is the only reasonable way to calculate the power output. Because we know that this kind of setup produces DRY STEAM and we can calculate the power directly from the reduced mass of the pot. –Jouni
