“The iron powder. That is the fuel source. When you ignite it, it burns at a high temperature.”
Oh, okay. Interesting fuel cycle - iron ore to iron powder to iron oxide, etc. I wonder if there’s really a net gain.
Sad to say not only is energy always conserved but you can't even break even. Some of the energy becomes waste heat. A typical heat engine (like a car) only converts about 20% of the chemical energy into useful work.