Two minutes. Real appliance draw numbers. Specific product names — not a watt-hour range that leaves you guessing.
What it does
Calculates your real watt-hour requirement from actual appliance draw — not nameplate ratings.
Surge warnings
Flags sump pumps, well pumps, and AC units that will trip an undersized inverter.
Real recommendations
Returns specific model names by tier — not a generic capacity range.
No signup needed
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This changes everything. A mountain hunter and a homeowner need very different systems.
Select everything you want to keep running. You can start small and expand later.
Choose the outage duration you want to plan for. Going longer gives more protection but costs more upfront.
Select your primary use case — home backup, medical devices, camping, RV, or off-grid. Each changes which appliances appear and how we model your duration needs.
Choose which devices need to run and for how long. The watt figures are real measured draw numbers, not nameplate ratings — nameplate ratings are almost always higher than actual consumption.
You get your minimum watt-hour requirement with a built-in 25% buffer for inverter losses. Surge warnings appear automatically for sump pumps, well pumps, and large motor loads. Products are named by tier.
No calculator replaces reading the actual spec sheet for your specific appliance. Wattage varies widely by model and age. If your application is critical — medical life support, sump pump in a flood-prone basement — verify numbers against your actual equipment before buying.
Well pumps above 1 HP and central air conditioning units generally exceed portable power station limits. The calculator flags these automatically but confirm with your equipment documentation.
How much fuel does a generator use to run for a day?
It depends on the generator's size and how hard it is working, but a portable unit covering a typical home-backup load burns roughly a quarter to a half gallon of gasoline per hour, with propane in a similar range. Run continuously, that is about 5 to 12 gallons of gasoline a day. The generator comparison built into the calculator above estimates the propane, natural gas, and gasoline your selected loads would need over your chosen outage length, using real manufacturer runtime figures.
How many gallons of gas does it take to run a generator for 3 days?
For a mid-size dual-fuel generator running around the clock, plan on roughly 25 to 35 gallons of gasoline over three days, about 5 to 7 five-gallon cans. A smaller inverter model sized to a light home load burns closer to 15 gallons, and propane is similar by volume. Select your appliances above and the calculator shows the amount for three real generator models.
Is a portable power station cheaper to run than a gas generator?
A battery power station has no fuel cost. You recharge it from the wall, a solar panel, or your car, while a generator burns fuel every hour it runs and needs oil and safe outdoor operation. For short outages the power station usually wins on running cost, noise, and convenience. For long multi-day outages a generator can refuel and keep going after a battery is drained, which is why many people keep both.
How do I calculate what size power station I need?
Add up the watt-hours each device uses in a day, which is its watts multiplied by the hours it runs, then multiply by the number of days you want to cover and add about 25 percent for inverter and battery losses. This calculator does that from real measured appliance draw and returns specific models by size tier.
Does the calculator account for startup surge on pumps and air conditioners?
Yes. It flags sump pumps, well pumps, and air conditioners, which can surge to several times their running watts at startup and will trip an undersized inverter. Running watt-hours size the battery, while surge decides whether it can start the motor at all. Where you can, measure your own device, since nameplate ratings usually overstate real draw.
Can a generator run on natural gas instead of propane or gasoline?
Some can. Standby units and a few tri-fuel portables run on a home natural-gas line, so there is no refueling and nothing to store, though you still pay for the gas you burn. Most portable generators are gasoline-only or dual-fuel for gasoline and propane and cannot use natural gas. The comparison in the calculator shows which fuels each example model supports.
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