If I were a modern doctor I wouldn't trust me either. Living in your sewer you miss all the drug ads with their side effects, which may include killing you with the illnesses they are supposed to cure. Come to think of it, you may be better off down there. "Ask your doctor if rat poison is right for you."

The turbine I guess is powered by all the dumpster vegetables you eat, plus you can light them if you get cold.

Here's a thought. If there is a prevailing direction to the bullets you could use them to power a turbine, freeing up the gas for more heating.

Trust me, I'm a doctor.