Best 40kW Natural Gas Generator: Top Tri-Fuel Portable Models
When selecting a tri-fuel generator capable of running on natural gas, core considerations include peak and running wattage, fuel flexibility, runtime, and transfer switch readiness. The following five models offer strong performance for larger homes or commercial-style backup needs, with natural gas compatibility and multiple fuel options. This guide highlights features to help compare capabilities, integration with home electrical systems, and safety features that support reliable, on-demand power.
| Product | Fuel Options | Peak Watts | Running Watts |
|---|---|---|---|
| Westinghouse 28000 Peak Watt Tri-Fuel | Gas, Propane, Natural Gas | 22,400 (NG) | 16,000 (NG) |
| Westinghouse 18000 Peak Watt Tri-Fuel | Gas, Propane, Natural Gas | 18,000 (Gas) | 12,000 (NG) |
| Westinghouse 14500 Peak Watt Tri-Fuel | Gas, Propane, Natural Gas | 13,500 (NG) | 9,500 (NG) |
| DuroStar DS13000MXT | Gas, Propane, Natural Gas | 13,000 (Gas) | 8,000 (NG) |
| WEN TF1450X | Gas, Propane, Natural Gas | 10,500 (NG) | 8,750 (NG) |
These options span a range of power output and fuel flexibility, helping homeowners and small businesses prepare for outages with natural gas as a reliable primary or secondary fuel source. Each model supports transfer switches and essential safety features for safe and dependable operation during emergencies.
Westinghouse 28,000 Peak Watt Tri-Fuel
The Westinghouse model combines tri-fuel versatility with a heavy-duty 999 cc V-Twin OHV engine and a robust, long-lasting cast-iron sleeve. It offers up to 22,400 peak watts when running on natural gas and 16,000 running watts, making it suitable for larger homes. The unit features automatic low-oil shutdown, a digital hour meter, and a comprehensive outlet lineup, including GFCI options and a transfer switch-ready configuration. With a large 17.2-gallon tank, it can run up to 13 hours at 25% load, depending on fuel choice. The design emphasizes durable portability with reinforced steel handles and quick-release pins.
DuroStar DS13000MXT 13,000-Watt Tri Fuel
Designed for whole-home support, the DS13000MXT delivers 13,000 watts of gasoline power, with propane and natural gas capability for added fuel flexibility. It includes a push-button start and a transfer-switch-ready 50-amp outlet to ease integration with home electrical systems. The unit’s Tri Fuel technology enables running on different fuels, offering options during fuel shortages or outages. The included CO alert helps monitor air quality and protect occupants, while the broad array of outlets accommodates multiple appliances and devices. This generator is positioned as a reliable emergency backup with robust fuel versatility.
Westinghouse 14,500 Peak Watt Tri-Fuel
Engineered for home backup and portable power, this model delivers 13,500 running watts and 12,000 peak watts when natural gas is used, with a heavier output on gasoline or propane. It features a durable 550cc Westinghouse OHV engine with a cast-iron sleeve and long run times (up to around 7-12 hours depending on fuel). The unit offers multiple outlets, including transfer-switch-ready options, and a CO sensor for safety. A sturdy power platform and remote start enhance convenience in adverse conditions, while the CO sensor adds a safety margin for indoor or semi-enclosed spaces.
WEN 14,500-Watt Tri-Fuel Generator
The WEN TF1450X provides a 14,500 surge watt and 11,500 running watts on gasoline, with propane and natural gas support that offers 12,500 surge and 8,750 running watts, respectively. It is designed for transfer-switch readiness and features an electric start with a CO watchdog for added safety. The generator operates at 120V/240V and includes a range of outlets suitable for home backup, RV use, and job sites. The CO monitoring system adds a critical safety layer during operation in enclosed spaces or during long outages.
Westinghouse 18,000 Peak Watt Tri-Fuel
With output across gasoline, propane, and natural gas, this model produces 18,000 peak watts (gasoline) and 16,000 peak watts on natural gas, plus 11,600 running watts on natural gas. It includes electric and remote start via a key fob, a 12-hour run-time on a sizable tank, and multiple outlets including transfer switch-ready and RV-ready configurations. The generator emphasizes a durable Westinghouse engine and a CO sensor system for safe, extended operation during outages. The combination of high power and fuel flexibility makes it a strong option for larger properties.
Westinghouse 8200 Peak Watt Inverter Tri-Fuel
This inverter-based unit blends tri-fuel capability with home backup power, offering 8,200 peak watts on gasoline and 6,560 peak watts on natural gas, with a 60 dBA-level noise footprint at 25% load. It includes a 50A transfer switch outlet and a TT-30RV outlet for RV use, along with multiple standard outlets. Inverter technology helps optimize fuel use and reduce noise, while keeping sensitive electronics safe with regulated voltage and cleaner power. The CO sensor supports safer operation in variety of settings.
Buying Guide: Key Purchase Considerations
- Fuel flexibility: Tri-fuel capability provides backup options if a single fuel source is unavailable. Natural gas is convenient for many households due to constant supply, but consider propan e and gasoline as backups.
- Power needs: Determine peak versus running watts to cover essential circuits during outages. For larger homes, prioritize higher peak watts and robust running watts across all fuel modes.
- Transfer switch readiness: Confirm whether the generator includes transfer switch-ready outlets or compatible interlock kits for seamless connection to home electrical systems.
- Outlets and safety: Look for a diverse outlet lineup (GFCI outlets, 30A/50A outlets, RV outlets) and safety features such as CO sensors, automatic low-oil shutdown, and safe start/stop mechanisms.
- Runtime and fuel efficiency: Larger tanks yield longer runtimes, but fuel type and engine design influence efficiency. Inverter-based units often run more quietly and efficiently at partial loads.
- Portability and build: Heavier tri-fuel units may require wheels, handles, and solid frame construction. For frequent relocation, prioritize mobility features and a rugged chassis.
- Maintenance and service: Consider engine displacement, oil change intervals, and ease of access for maintenance. Check warranty terms and availability of replacement parts.
- Noise considerations: Inverter models tend to run quieter, which matters in residential neighborhoods with noise restrictions.
- Safety and CO monitoring: CO sensors add critical protection when operating in semi-enclosed spaces. Verify integration with alarms or shutdown features.
- Cost of ownership: While prices vary, evaluate total ownership costs including fuel usage, maintenance, and potential parallel operation with other units.