Both natural gas and diesel engines, along with gen sets, have proven performance and reliability. Diesel has a higher power density and can reach full load more quickly than natural gas; however, natural gas generators can meet the <:10 minimum startup time required for emergency power supply systems. Once started, reliability and performance of diesel, natural gas, and bi-fuel generators are equivalent. Diesel generators have a higher overall efficiency.
Natural gas is one of the cleanest fossil fuels to use. Emissions of sulfur, nitrogen, and carbon dioxide (a greenhouse gas) are considerably lower when compared to diesel fuel. Diesel engines also emit more nitrogen oxide and particulate matter than similar spark-ignited units, which has led to increased scrutiny from the Environmental Protection Agency (EPA). Intense emission level regulations and aggressive tier changes from the EPA could eventually result in diesel engines being taxed at a greater rate due to their higher carbon dioxide emissions. In addition, the high level of emissions produced by diesel gensets may increase the difficulty in procuring an air-quality permit. Obtaining an air-quality permit for natural gas units is easier because they produce fewer harmful emissions. For companies that emphasize a core value of “being green”, natural gas is the best fuel choice in most situations.
Generator maintenance programs shouldn’t be overlooked and it’s important to understand the extra human effort needed to keep a diesel generator operating at peak condition compared to a gaseous-fueled unit. Read the Article