Diesel generators use comparatively less fuel and thus are more fuel efficient than power generated by gasoline or natural gas. For every liter of fuel consumed, diesel generators can run 2 to 3 times more efficiently than natural gas engines. There is no need of frequent maintenance for diesel engines, but gasoline engines need more frequent maintenance. Most diesel engines designed with water-cooled engine up to a speed of 1800 rounds per minute. This makes sure that the engine is durable, and makes it most dependable of all generators.
Unlike other natural gas generators and gasoline generators, diesel engines are very safe to use because they work on direct injection principle and they do not have any spark plugs. The unavailability of spark plug keeps them safe from fire. Diesel generator has a better shelf life. This is the least flammable source of fuel, hence can be stored for more time.
The fuel for the diesel generators is available at all gas stations and can be collected in comfortable cans. Main problems in case of diesel generators are: it is very hard to start them in cold weather, they are noisy and emit more smoke. Home diesel generators may cost $ 800 for 4 kilowatt to $10000 for a 15-kilowatt depending upon the rating, voltage consumption, quality and brand name. Diesel generators can also be used in industrial purposes. For industrial purpose they are available in range of 500 kilowatt to 2000 kilowatt.
Fuels such as diesel, gasoline, natural gas, or propane can basically power home generators. Some models of diesel generators also designed with multi fuel capabilities. The fuel choice of will depend on availability of fuel during emergency times.