10 Best Diesel Generators 2025 in the United States

The Generac Guardian 22kW Home Standby Generator is a powerful option for homeowners seeking reliable backup power during outages. It delivers a strong 22,000 watts of clean and stable electricity, enough to cover an entire house comfortably. Its engine is designed to be fuel-efficient and quieter than many comparable generators, which helps reduce noise disturbance during use. The unit runs on natural gas or propane, which are convenient and readily available fuel sources for many users.

One standout feature is the included 200 Amp automatic transfer switch, which seamlessly switches your home’s power to the generator when the main power goes out—meaning you won’t have to lift a finger during an outage. The transfer switch is also built to last with a five-year warranty and is housed in a weatherproof aluminum enclosure for outdoor installation. The generator comes Wi-Fi enabled, allowing you to monitor its status and maintenance alerts remotely via an app, providing extra convenience and peace of mind.

In terms of size and weight, it’s a heavier and less portable unit (466 pounds), so it’s best suited for permanent home installation rather than moving around. Maintenance needs are relatively low thanks to the durable G-Force engine, but professional installation and occasional servicing by a licensed electrician are recommended to keep it running smoothly. Though this generator is on the pricier side and installation can be involved, its combination of power, reliability, and smart features makes it an excellent choice for homeowners wanting a dependable whole-house backup power solution.

The DuroMax XP15000HX is a powerful portable generator offering 15,000 watts of starting power and 12,000 watts running power, suitable for whole-home backup during power outages or for commercial use. One of its biggest advantages is dual fuel capability, allowing you to run it on gasoline or propane. Propane is cleaner, more fuel-efficient, and easier to store long-term, which can save money and reduce maintenance. It features a robust 670cc engine and durable all-copper windings designed to extend its lifespan. The generator is transfer switch ready, meaning it can easily connect to your home’s electrical system for seamless power backup.

Its control panel is user-friendly, with a digital display showing voltage, frequency, and maintenance reminders, plus a convenient push-button start and remote control. Safety is enhanced by a CO Alert system that shuts the generator off if dangerous carbon monoxide levels are detected. Despite weighing 345 pounds, it includes wheels and a handle to help with moving it around, though it is still better suited for those who need a relatively heavy-duty, stationary backup rather than light portability. Maintenance is supported with included tools and clear indicators for service intervals.

This generator is an excellent option for anyone needing reliable, flexible power backup or a generator capable of handling high loads, especially if you want the option of cleaner propane fuel. However, its weight and size may make it less convenient for frequent transport or casual recreational use.

The Westinghouse 28000 Peak Watt Home Backup Portable Generator is a robust option for anyone needing a reliable backup power source, particularly for residential use. With a peak output of 28,000 watts and running at 20,000 watts, it delivers significant power, making it suitable for larger appliances during an outage. The generator features an easy-start mechanism with a remote key fob and push-button electric start, which simplifies operation and adds convenience.

One of its standout strengths is the impressive run time of up to 11 hours at half load, thanks to the sizable 17-gallon fuel tank. This extended run time combined with its automatic low oil and carbon monoxide shutdown enhances safety and usability. Portability is manageable despite its 599-pound weight, as it includes reinforced steel handles, making it easier to move when necessary.

There are a few drawbacks to consider. While it offers multiple outlets for various connections, the generator can produce noise levels that may be disruptive, especially in quieter neighborhoods. Additionally, maintenance may be more involved due to its 999cc engine, which could be a concern for those unfamiliar with engine upkeep. Westinghouse backs this generator with a 3-year limited warranty and nationwide service, providing reassurance. Users looking for a powerful, versatile, and relatively easy-to-use generator for home backup will likely find the Westinghouse model meets their needs well. However, those sensitive to noise or with limited experience in maintaining large engines might want to explore simpler alternatives.