August 10, 2026 – Home Owners
When a storm knocks out the power, a propane standby generator can help keep your home running. Heat, refrigeration, well and sump pumps, lights, and Wi-Fi can stay on. The generator runs on propane stored in a tank on your property and starts automatically within seconds of an outage, whether you are home or away.
In the Northeast, outages can happen suddenly. Summer storms can bring down power lines, while winter nor’easters can strain the grid with ice and heavy snow. When the power goes out, the homes that stay powered are often the ones that planned ahead. This guide explains why propane is the smart choice for backup power, the difference between standby and portable generators, how long a generator can run on propane, and how to choose the right generator and tank size for your home.
Why propane is a strong fuel for backup power
The fuel is already at your home when the grid fails. Because propane is stored on your property, your generator has access to fuel even when the electric grid is down. No need for a last-minute fuel delivery or depend on the infrastructure that may be affected by the outage.
Propane stores well over time. The Propane Education and Research Council describes propane for standby power as stable, available energy that does not degrade over time (PERC, 2026), like some other liquid fuels, the propane in your tank can stay ready for future outages, whether that happens during a summer storm or a February nor’easter.
It burns clean and keeps the supply out of sight. Propane is a clean-burning and efficient fuel, making it a strong choice for standby generators. It can help provide reliable backup power for your home while producing fewer emissions than many traditional fuel options.
Paraco supplies propane for generators across the Northeast. If your home already runs on propane for heating or appliances, a generator can often work from your existing supply.
Standby vs portable generators
A standby generator is permanently installed, starts automatically, and can power most of your home. A portable generator is smaller, must be started by hand, and is usually used for a few appliances at a time. Which one fits depends on how much of your life you want running during an outage.
A standby unit sits on a pad outside the house, connected to your electrical panel through an automatic transfer switch. When the grid drops, the switch senses it and starts the generator within seconds. When power returns, the unit shuts itself down and goes back to watching.
A portable generator is a lighter-duty option. It can help keep a few appliances running during short outages, but it must be started manually and used outdoors only, far away from windows, doors, and vents because of carbon monoxide risk. Our generators page covers both options in more detail.
The honest trade-off: a portable generator can be a lower-cost option for short outages, but it has limits. A standby generator is a true home backup system, designed for homes that lose power more often or need to keep essential systems running, such as heat, a well pump, sump pump, or medical equipment.
How long will a generator run on propane?
For most homes, the answer is days, not hours. A properly filled 500-gallon propane tank can help power a generator continuously for roughly 4 to 6 days, depending on load and household usage.
Generac’s published specifications for its 22 kW home standby model list propane use of 2.53 gallons per hour at half load and 3.71 gallons per hour at full load (Generac, 2026). As a general example, a 120-gallon tank may provide about a day and a half of run time at half load, while a 500-gallon tank may provide several days of backup power. Actual run time will vary based on the generator load, tank size, household energy use, and the amount of propane available in the tank.
In most outages, a generator does not run at full power all day and night. It uses fuel based on how much power your home needs at the time. Turning off items you do not need, like extra lights, a second refrigerator, or large electric heating loads, can help reduce propane use and make your fuel supply last longer. For context, each gallon of propane carries about 91,500 BTU of energy, a BTU being a standard unit of energy, which the generator turns into electricity for your home.
Paraco tip: After any extended run, check your gauge or have your supply checked. A tank that carried you through a three-day storm has done its job and will need a delivery before the next one.
Sizing the generator and the tank
Your generator should be sized based on what you want to power during an outage, and your propane tank should be sized based on how long you want that backup power to last. A licensed professional can calculate your home’s power needs, while your propane supplier can help make sure the tank and gas lines are properly sized for the generator.
Generator sizes are fairly straightforward. Portable generators are usually smaller and can power a few important appliances during a short outage. Air-cooled standby generators, often in the 10 to 26 kW range, can power key home systems and, in some cases, much of the home or the entire home, depending on the size of the generator and the home’s needs. For larger homes and businesses, liquid-cooled generators can provide a higher level of backup power. They are often used where downtime is not an option, from restaurants protecting refrigeration to offices keeping essential systems online.
Standby generators use propane from an installed tank on your property. Depending on your home’s needs, that tank may range from a smaller residential size to a larger 500 or 1,000 gallon tank. Paraco installs propane tanks from 56 to 1,000 gallons, with both above ground and underground options available. The right setup depends on how much propane the generator uses, whether the same tank also supplies your furnace or appliances, and how long you want backup power to last. Every home is different. Some homes may be able to use an existing propane tank, while others may need added capacity or a separate tank for the generator.
A standby generator should be installed by licensed professionals. From placement and clearances to the transfer switch and gas lines, every part of the setup needs to follow manufacturer instructions and local codes. That professional installation is what helps make the system safe, reliable, and ready to turn on automatically when the power goes out.
Keeping fuel ready between outages
A generator is only as ready as the tank behind it. Automatic delivery for installed tanks, tank monitoring, and routine service on the manufacturer’s schedule are what keep a standby system genuinely standby.
Supply first. Paraco’s automatic delivery projects your usage and schedules deliveries before you run low, with monitoring options that watch the gauge so you do not have to. It is designed to keep your supply ready through the seasons. If your generator shares a tank with home heating, that matters twice in winter, when the furnace and an outage can draw on the same supply.
The machine needs attention too. Standby units run a brief self-test on a weekly or biweekly schedule, and an annual service on the manufacturer’s instructions keeps oil, filters, and the battery ready for a real event. A quick glance at the unit’s status panel after each self-test is a habit that pays for itself.
Picture the system working as designed. An ice storm takes the neighborhood dark on a Friday night. The transfer switch catches it, the generator is carrying the house before anyone finds a flashlight, and the furnace, refrigerator, well pump, and Wi-Fi barely notice. Because the tank was on automatic delivery, the home had propane ready before the weekend outage. And because the generator had been serviced, it started automatically and kept running when it was needed. By Sunday, the power was back, the generator shut down on its own, and the only follow-up was confirming a propane delivery to replace the fuel used during the outage. That is the value of standby power: turning an emergency into a more manageable situation.
Frequently asked questions
How long will a whole house generator run on propane?
It depends on the generator size, how much power your home is using, and the size of the propane tank. As a general rule, many air-cooled home standby generators use about 2 to 4 gallons of propane per hour, depending on load. With a properly filled 500-gallon tank, many homes can have several days of backup power, and even longer when non-essential appliances are turned off.
How much propane does a generator use per hour?
Generac’s published figures for its 22 kW home standby model are 2.53 gallons per hour at half load and 3.71 at full load; smaller units use less and large liquid-cooled units use more. Check the fuel consumption table on your model’s spec sheet for the exact numbers, then plan the tank around them.
What size propane tank do I need for a standby generator?
Most home standby generators are paired with an installed propane tank ranging from 120 to 1,000 gallons. The right tank size depends on your generator, whether the tank also supplies heat or other appliances, and how long you want backup power to last during an outage. Your propane supplier and a licensed professional can help size the generator, tank, and gas lines as one complete system.
Can a propane generator power my whole house?
With the right generator size, yes. Air-cooled standby generators, often in the 10 to 26 kW range, can power key appliances and important home systems for many homes. In some cases, they may support most or all of the home. Larger homes and businesses may need a liquid-cooled generator. A licensed professional can calculate your home’s power needs and recommend the right size generator.
Does propane go bad if the generator rarely runs?
No. Propane is stable in storage and does not degrade over time, making it well-suited for standby generators that may sit idle between outages. As long as your tank has enough propane and your generator is serviced according to the manufacturer’s schedule, the system can stay ready when you need it.
Be ready before the next outage
Propane is a smart fit for standby generators because it does not degrade over time, is stored in your tank, and is ready when the power goes out. Paraco can help with the fuel side of your backup power setup, from tank sizing and installation to automatic delivery. Talk to our team about making your home or business generator-ready.