Comment by seabrookmx

The maintenance difference isn't that large. Diesel in a good tank also lasts an extremely long time, unlike gasoline. Diesel engines are more thermally efficient so you get more electricity per unit of fuel burned. The tanks don't need to be under pressure or replaced nearly as often as those for propane either. This is why most hospitals, data centers etc. that aren't near a natural gas line use diesel generators not propane. Natural gas has the benefit that when piped in, you don't need storage at all.