What Kind of Generator do I Need for my House?
How to Get the Right Generator for Your Home
Electricity is one of the modern conveniences we take most for granted.
All it takes is a short power outage to remind us how completely reliant we are on electricity and makes us wonder how our ancestors spent most of human history without it.
With today’s aging infrastructure and severe weather, the frequency and duration of outages could increase, but we don’t have to remain powerless. There are many types of backup generators for your house that can keep daily life flowing during a blackout.
Generators for Your House
There are different types of generators for home use, depending on where you live and what you need to power. The following sections outline different scenarios you may fall under and which generator would be the best investment.
Houses with Occasional Power Outages
If you live in an area with reliable power (underground power cable) and without major hurricanes, wildfires or other disasters that regularly interrupt your power supply, then a portable generator is your best bet. They are great for houses that suffer only a few, short outages per year.
All portable home use generators will require manual operation whether you connect them to appliances with an extension cord or connect them directly to the circuit using a manual transfer switch. If you choose the transfer switch, it needs to be installed by a professional.
You will also need to decide on a fuel source. Diesel, gasoline, and propane are commonly available fuel types, but you can also get solar, dual-fuel or even tri-fuel options. These alternative fuel options could prove useful in disaster situations where there might be a gas shortage.
Remember to refill; otherwise no power. Also, NEVER run generators indoors or less than 10 feet away from doors or windows because they produce deadly carbon monoxide in their exhaust.
Portable generators can further be narrowed down by their wattage output. The following are general wattage guidelines. To find actual starting and running wattage requirements, you will need to check your appliances or their manuals. Older, less efficient appliances might require extra watts to power larger motors.
PRO TIP: Don't be fooled by stores that only advertise "starting watts." Check our guide for a full explanation of running versus starting watts and how to calculate them.
Portable Generators by Wattage
Below are estimates of what different portable generators can power based on their wattage. Each generator's runtime will vary depending on how many appliances it's powering. Always consult the generator's product manual or view our product page to know its specific power limits and run times.
- Small portable generators
Provide less than 3,000 watts and are great for short power outages when you need it to last a few hours. They will power your essentials—lights, microwave or refrigerator. Keep in mind that the more appliances you attempt to power, the less overall runtime you will have.
- Medium portable generators
Provide 3,000-6,000 watts and are still meant for essentials but have larger fuel tanks, so that they can power more of them for longer. Here, you might have the luxury of cooking dinner in the microwave while the fridge stays on and your sump pump keeps the basement dry.
An added benefit to small and medium portable generators is their ease of transportation for activities like camping. Large and Extra-large generators are semi-permanent and cannot easily be moved.
- Large portable generators
Provide 6,000-9,000 watts and can power multiple rooms when used with a manual transfer switch instead of an extension cord (which is safer). They can handle virtually every appliance except for certain pieces of hardwired equipment, which require a high number of surge or starting watts.
- Extra-large portable generators
Are the largest of the portable options, providing 10,000 watts or more. These generators often come with an electric start button and are used with a manual transfer switch to power hardwired equipment like well pumps, a central furnace, security systems, etc. If the severity of power outages in your area justifies purchasing one of these, you may want to consider a standby generator (see below).
Know that if you want to power sensitive electronic devices, such as computers, phone chargers, and newer, high-tech refrigerators, you will need a generator with a total harmonic distortion (THD) of less than 5%. THD refers to how “clean” the electricity is.
A generator with high THD could potentially fry electronics and is an important consideration. If you absolutely need to keep sensitive equipment powered, then an inverter or standby generator, which produces clean power, is the solution.
If you need help sizing your portable generator, use our generator wattage calculator to figure out your power needs. Just choose which appliances you want to power, and the calculator will give you a range of generator options.
Houses with Frequent Power Outages
If you live in a hurricane zone or can count on regular natural disasters, you should consider installing an automatic home standby or whole house generator. Even if you don't, it's nice having the security that a standby provides.
Portable generators are not designed to be used for days or weeks on end, which might be how long you need to wait for utility power to be restored in a storm’s aftermath.
A standby generator differs substantially from a portable generator in the following ways:
Permanent: Unlike a portable unit, which needs to be rolled or carried around, whole house generators are installed one time by an electrician. Natural gas, propane, diesel, and dual fuel models are available to power the standby.
Automation: Standby generators use automatic transfer switches, which connect to the circuit breaker board in a house. When utility power goes out, the automatic transfer switch turns the standby generator on to energize the entire home without you having to lift a finger.
Output: While the largest portable generators produce around 17 kilowatts, standby generators can generate 150 kilowatts or more of clean power that can handle all your appliances, even sensitive electronics. They must do so to power your entire house for days or weeks.
HVAC: Many homeowners wonder what size generator they need to run an air conditioner. Standby generators will do the trick, and that is what we always recommend for those applications. Portable generators cannot reliably keep a central air conditioning system running, especially since they typically cannot handle the watts requiring to start the system (surge watts).
The size of your standby will depend on your home’s power needs, especially when it comes to the a/c system. Use our Home Standby Generator Sizing Calculator to find the right size.
Generators for Mobile Homes
For those in mobile or manufactured homes, the same principles apply as in the above two sections.
- For mobile homes in locations with short, infrequent power outages, a portable generator will be your best bet. Keep in mind that some mobile home parks may have noise restrictions, so find out the generator’s decibel rating. Quiet, inverter generators are a great solution for meeting noise requirements and short-term power needs.
- Mobile home owners in locations with frequent power outages could potentially install a standby generator. Be sure to check with your mobile home park before pursuing this option, however.
If you have an RV, there are specific generator requirements. Check out our RV Generator Buyer's Guide for more details.
Generators for Apartments
If you live in an apartment, you cannot use any gas-powered generators unless you can keep it outside at least 10 feet away from doors or windows. The exhaust from the combustion engine contains carbon monoxide, which is deadly.
Most likely, you will need a solar-powered portable generator. In addition to using solar panels, these units can also charge through a wall outlet when you have utility power and be ready to go when you lose it.
They are small, low-wattage (160-3,000 starting watts) generators but can power your essentials for several hours assuming you don’t have too many appliances plugged in at once. For example, some units can power a refrigerator for 10-14 hours if that is the only connected appliance.
Solar generators can also power your sensitive electronic equipment because they produce a perfect sine wave of electricity and have zero THD.
Buying a Generator for Your House
As you can see, there’s a power solution no matter what your living arrangement. Now that you know how to choose a generator for home use, you will be able to keep taking electricity for granted during a power outage. After all, why should you ever have to live without it?