Fuel-source reliability and environmental regulations or concerns are the primary reasons why organizations select natural gas generators for standby or backup power. Where generators may go long periods without being run other than for testing, concerns about long-term diesel storage is also a concern.
These considerations are not insignificant, making the choice of natural gas a necessity, or even a directive, for many firms. Natural gas is also less expensive than diesel, although it generally takes much longer to recapture the cost differential for a standby natural gas generator (as compared to diesel) than for a prime power unit.
The availability of underground natural gas lines gives natural gas generators a reliable fuel supply if above-ground disasters strike. Having a continuous supply eliminates the need for fuel storage and scheduled deliveries. This enables natural gas backup generators to meet the rigorous guidelines of cities and other urban areas concerned with the possibility of fuel tank explosions.
In urban areas, local or state governments may have enacted regulations prohibiting the use of diesel engines due to emissions concerns. Even though the current generation of diesel engines burns far cleaner than in previous years, natural gas is still considered a more environmentally friendly choice.