Actually, knowing it works now. Even internal combustion engines have only a 40% energy efficiency in converting gas to power, the rest is lost as heat. In thi

Actually, knowing it works now. Even internal combustion engines have only a 40% energy efficiency in converting gas to power, the rest is lost as heat. In this case, I'm trying to think how the wind energy is lost, and it seems that some of that might be lost to the static friction in turning the wheels, and also the attached propeller. However, the energy used to turn the propeller is outputted again, as thrust. Since the initial wind was enough to overcome the static friction, any additional power might be causing it to move faster than the wind. I'm no physicist, but this is pretty cool.