What Size Gas Generator Do You Need to Run a House?
Generators provide emergency power solutions when needed; some models can even provide enough power for an entire home. According to the U.S. Energy Information Association (EIA), Americans consumed 32.50 trillion cubic feet of natural gas in 2023.
If you’re interested in a gas generator, it’s vital to understand important facts like what size you’ll need.
Our guide is here to help you learn what size gas home generator is required to reap the benefits of this effective home energy source.
Small vs Whole Home Generator
Small, portable gas generators work well to provide power to tools or individual appliances. However, a whole-home generator is considerably different from its much more compact counterpart.
First, larger gas home generators use an automotive-style engine instead of a lawnmower-style engine. Second, instead of using air-cooling technology, larger models use liquid-cooling technology for longer runtimes to prevent overheating.
A whole-home generator is typically much quieter since it requires lower RPMs or rotations per minute to operate. These larger generators also require a lot less maintenance, so they’re easy to turn on and use whenever you need them.
A small gas generator needs frequent refilling. However, larger gas generators designed to power an entire home are much more fuel-efficient overall.
Portable gas generators are helpful if you need a quick and temporary power source. If you need something long-lasting that can power your entire home, a whole-home gas generator is the best choice.
How to Determine the Right Size
Choosing the correct size for your home gas generator is crucial, and it’s a decision that is usually best left to the professionals. You’ll need to know the load requirement of everything in your home, particularly all our home’s major appliances.
The manufacturer’s data plate should have information about each of your appliances’ requirements. Once you have this information, you can use this formula to determine the total starting wattage for each appliance:
- Starting Amps x Volts = Watts
If you need to calculate kilowatts, divide the total number of watts by 1,000. These numbers make it easier to determine total amperage requirements, but there are many other things you’ll need to provide power to in your home like lights, well pumps (when applicable) and HVAC units.
It’s best to select a generator output rating that’s approximately 20-25% higher than the peak load. If your total required wattage is 23 kilowatts (kW), a 28 kW generator should suffice.
Higher-rated generators can operate at nearly 80% of their full capacity. This helps you get more flexibility in case your home’s load increases in the future.
Central air conditioning tends to draw the most wattage. You can determine your air conditioner’s size in tons by using this formula:
- Number of BTUs/12,000
This figure will show you the air conditioner’s size in tons. Of course, the final size you’ll need depends on several factors like the size of your home, how many appliances you have and how often or how long you expect to experience power outages.
Gas Generators: Wattage Examples
Let’s take a closer look at gas generators in watts and how many watts are required to power various appliances in your home. A smaller, 5,000-watt gas generator can power things like basic lights and your refrigerator and freezer.
A gas generator at 15,000 watts powers everything already mentioned as well as your home’s AC or heating, your water heater, an oven or stove, a microwave and your TV. If your home is small and you need a starter whole-home or “standby” gas generator, 22,000 watts should suffice.
Gas generators of 25,000-watt can power most households including your central AC or heating, major appliances, water heater, garage door, and more. Generators between 27,000 and 36,000 watts replace 75% of the 200 amps that are now standard for most electrical panels. In general, 15,000 to 30,000-watt gas generators are a practical and reliable option to power a whole home and not just specific appliances or components.
As an example, the average refrigerator requires 700 watts and a TV requires between 100 to 150 watts to operate. Laptops require around 200 watts while most smartphone chargers only require 20 watts. A home security system typically needs 100 watts and it takes around 250 watts to run between five and 10 lights.
These numbers are just a general range to help you understand exactly what size generator you’ll need. The more appliances and items you need or want to power, the more wattage your generator should produce.
Gas Generator Safety
Although modern generator technology is designed to be safer than ever, there are still some safety protocols homeowners should follow. Here are some tips to ensure you use these efficient home power solutions safely:
- Consider installing carbon monoxide detectors to alert you of a possible gas leak
- Make sure your gas generator is chosen and installed by professionals
- Your gas generator should have its own built-in CO sensor that turns the unit off in the event of a leak
- Ensure the generator is installed at the appropriate safe distance from your home
- Choose a generator with a warranty to cover repairs or damage
- Regularly inspect gas lines to ensure they’re safe and leak-free
- Check the generator’s connection to your electrical panel annually
- Never try to install a whole-home gas generator yourself
- Get a generator with automatic startup so you don’t have to go outside in the dark to turn it on
These simple tips will keep you, your home, and your family safe after you get a whole-home gas generator. Regular inspections and maintenance for your new generator also protect your investment and your property.
Power Your Home in Any Situation
A standby gas-powered home generator provides you with reliable backup power in the event of an emergency. Choosing the correct size will make all the difference between giving you the power you need for just a few appliances or the power you need to keep your entire home running smoothly.
Our experienced team can install and service all makes and models of gas generators and more. If you’d like to purchase a generator or want to learn more about our services, see our generator selection or request a quote to start your installation.