How much energy can we make per gallon of diesel fuel? I'll be testing an Army generator's fuel economy while re-charging my off grid solar battery bank.

The military generator is model MEP-831A. It's a single cylinder, Yanmar L-70 diesel engine. In the winter, there isn't enough solar energy to keep my battery bank full. I supplement my off grid system with a generator. I'm curious which generator is the most efficient.

In past videos I've tested my Honda EU6500 gasoline generator, and I've tested my home-built Harbor Freight generator using a car alternator.