This is a "dumb engine". no throttle, low pressure, low temperature. It runs at 12 or 13% overall efficiency. All our other engines are "supercritical", 1,000F, 3200 psi. We are in the 30's, better than gas, worse than Diesel, but we can burn s**t for fuel. We have run algae, powdered coal, used crankcase oil, cooking oil, ethanol, butane, you name it. We also have an engine that does not breathe air. The exhaust is club soda, water and CO2. Fun stuff here...........