How to Determine Which Whole House Generator

Is Best for You 

Great Backup Power Option 


A whole house generator can provide back-up power for your entire home, including for essential appliances like your air conditioner, sump pump and refrigerator. Property estimated and installed, you should be able to run everything at full capacity, whether you’re going off the grid permanently or you’re forced off temporarily due to an emergency. 

Consider four primary elements when choosing a whole house generator: power requirements, cooling systems, fuel types and noise levels. 

Power Requirements 

To determine how much power you’ll need for your generator, you can either use an online wattage calculator, the wattage information on your appliances or your electrical bill. We recommend multiplying the total wattage of your appliances by 1.5 to give yourself a safe margin of error. A small to medium-size house in the U.S. typically uses a minimum of 5,000 to 7,000 watts, so you should expect most generators to have a minimum of 8,500 to 10,000 watt outputs. 

Cooling Mechanisms 

When you’ve determined what power level you need from your whole house generator, you should consider whether you want an air-cooled or liquid-cooled system. An air-cooled generator either passively uses the surrounding air to cool the engine or relies on a fan to maintain temperature. 

Liquid-cooled generators pump coolant through the engine block. This coolant absorbs heat from the engine, then is cycled through to the radiator, where it cools off, then moves back to the engine to maintain an appropriate temperature. 

Air-cooled generators are usually less efficient, and they tend to have shorter shelf lives when used in whole-house contexts. They often overheat and then automatically shut down. Liquid-cooled generators tend to work best, particularly if you live in an area that often reaches temperatures of over 100 degrees, because they are much less likely to overheat. 

Fuel Types 

Whole house generators either use liquid propane from a tank or natural gas from a utility line (or custom tank). Propane is cheaper and less contaminating, but using natural gas means you won’t have to refill a tank (although this isn’t an option if you’re looking to go off the grid). 

Be sure to purchase the right type of generator for the fuel you’re looking to use, or check to see if it can be easily converted from one fuel source to the other (most can be). 


Choosing the right whole house generator based on your budget involves careful consideration of your power needs and available options. While these generators offer excellent backup power solutions, your choice should align with your financial constraints. 

Understanding your budget is the first step. Whole house generators come in various sizes and capacities, each with a corresponding price range. Smaller generators that power essential circuits will typically be more budget-friendly than larger units that supply power to the entire house. 

It’s essential to balance your budget and your power requirements. Assess your essential appliances and systems that need backup power during outages. This evaluation will help you determine the generator’s capacity that suits your needs without overspending. 

Transfer Switch 

When shopping for a whole house generator, it’s important to make sure you purchase the right transfer switch. This component is a crucial link between your generator and your home’s electrical system. It’s what enables a seamless transition to backup power during outages. 

You’ll want to assess your power demands to choose the ideal transfer switch for your whole house generator. The size of your generator dictates the transfer switch capacity you’ll require. A transfer switch that aligns with your generator’s output ensures efficient power distribution across your household circuits. 

Simultaneously, factor in the complexity of your electrical system. Automatic transfer switches offer effortless power restoration by detecting outages and facilitating a smooth switch to generator power. They’re particularly beneficial for those seeking a hands-off experience. On the other hand, manual transfer switches are more budget-friendly and necessitate manual intervention to redirect power. Weighing convenience against cost-effectiveness is crucial. 

Noise Level 

Whole house generators can run quite loudly (65 decibels on the low end to 69+ on the high end), so it’s important to take that range into consideration when purchasing and placing your generator. 

Best time to purchase is early fall or spring.