Types of Generators and Fuel Economy
Generators or "gensets" come in various fuel choices that include gasoline, propane, natural gas and diesel. Cheaper gensets are built around gasoline engines running at 3600 rpm. Bigger industrial units tend to use natural gas, diesel or propane with a slower and more frugal 1800 rpm engine. Your model choice depends on factors such as unit capital cost, accessibility to fuel source, ease of use and economy.