“When the gas chamber is heated from the outside, with anything from burning wood chips to charcoal, the gas expands, creating pressure. That pressure drives a piston from the hot chamber into the cool chamber. In Kamen’s design, that mechanical power achieves two goals: it creates electrical power, 300 continuous watts – enough to run a few electrical devices - and, as a bonus, creates enough heat to distill contaminated water, making it drinkable.”
What prevents me from plugging a hotplate into the 300 watts and placing it where the coals are? The hotplate heats one side, convection cools the other side creating the force that drives the engine. Of course, it wouldn’t be self-starting, I assume you’d need a heat source (coals, butane, propane) to get the engine to develop it’s initial 300 watts, but shouldn’t it run almost continuously after that? At least until the ‘equalization’ occurred?
The problem is that you wouldn’t be able to get enough heat out of the hot plate to get the stirling going. The power plant might generate 300 watts, and the hot plate might produce 300 watts of heat, but it’d take (wildly grabbing numbers) 350 watts of electricity to produce that heat, due to losses inherent in the system.