| Diesel Generator Sets | Approximately 5 kVA to more than 3,000 kVA | Diesel fuel | Single-phase or three-phase AC; 50 Hz or 60 Hz versions | Radiator-based liquid cooling; smaller units may use air cooling | Factories, construction sites, telecommunications, hospitals, data centers, and standby power systems | High durability, strong load capacity, reliable long-duration operation, and broad power coverage |
| Gas Generator Sets | Approximately 20 kW to several megawatts | Natural gas, biogas, landfill gas, or other approved gaseous fuels | Usually three-phase AC; commonly configured for continuous or standby operation | Liquid-cooled engine systems | Commercial buildings, industrial facilities, combined heat and power systems, and distributed energy projects | Lower local emissions than conventional diesel units when supplied with suitable natural gas |
| Gasoline Portable Generators | Approximately 0.8 kW to 15 kW | Gasoline | Single-phase AC, often with 12 V DC auxiliary output | Air-cooled | Home backup, outdoor activities, small workshops, agricultural work, and emergency use | Lightweight design, simple operation, and relatively low initial purchase cost |
| Inverter Generators | Approximately 1 kW to 8 kW | Usually gasoline; some models support liquefied petroleum gas | Stable single-phase output produced through AC-DC-AC conversion | Air-cooled | Sensitive electronics, recreational vehicles, camping, residential backup, and mobile work | Lower noise, improved fuel efficiency at partial load, compact size, and clean voltage waveform |
| Dual-Fuel Generators | Approximately 2 kW to 20 kW for portable models | Gasoline and liquefied petroleum gas | Primarily single-phase AC; selected larger systems are three-phase | Air-cooled or liquid-cooled, depending on output rating | Residential backup, emergency response, mobile services, and remote work locations | Fuel flexibility and extended operating options when one fuel is unavailable |
| Natural Gas Standby Generators | Approximately 8 kW to 150 kW for residential and light commercial systems | Pipeline natural gas or liquefied petroleum gas | Single-phase or three-phase AC with automatic transfer switch compatibility | Liquid-cooled on higher-output models; air-cooled on smaller units | Homes, offices, retail facilities, farms, and small commercial buildings | Automatic emergency start capability and no on-site diesel storage requirement |
| Solar-Battery Generator Systems | Approximately 0.5 kWh to more than 20 kWh of stored energy per system | Solar photovoltaic modules and rechargeable batteries | Inverter-based AC output with DC charging and storage functions | Passive or fan-assisted battery and inverter cooling | Backup power, outdoor use, disaster preparedness, telecommunications, and off-grid applications | Quiet operation, zero fuel combustion during use, modular expansion, and low routine maintenance |
| PTO Generators | Approximately 10 kW to 150 kW | Mechanical power from a tractor power take-off shaft | Usually three-phase AC; some models provide single-phase output | Air-cooled or fan-assisted alternator cooling | Agriculture, livestock farms, irrigation systems, and rural emergency power | Uses existing tractor equipment and can reduce the need for a separate engine |