Generator Fuel Cost Per Day
Enter your generator, its fuel, the load and the hours a day you'll run it, pick your state, and see the gallons and dollars per day, plus what each kWh it makes costs you.
Generator fuel cost
E02Scenario A
Sets the electricity rate. Pick US average if you're not sure.
From EIA for US average. Use the rate on your bill if you know it.
Rate used: 18.4¢/kWh · US average · EIA reference 2025–26 · gasoline $3.20/gal · propane $2.60/gal · heating oil $3.70/gal (data as of 2026-09-26) ·
Estimated fuel cost per day
$0.64 per kWh generated, against 18.4¢/kWh from the grid in US average.
- Gallons per day
- 9.0
- Cost per day
- $28.80
- Cost per hour
- $2.40
- Cost per kWh generated
- $0.64
- Fuel price used
- $3.20/gal (US average) · EIA/AAA, 2025–26 reference (data as of 2026-09-26)
Estimate. Formula and sources are under “How it works”. Change any input; the result updates as you type.
Formula
How it works
- Gallons per day = gallons per hour at your load × hours per day (gallons per hour as in the generator runtime calculator)
- Cost per day = gallons per day × fuel price in your state
- Cost per hour = gallons per hour × fuel price
- Cost per kWh generated = cost per hour ÷ (generator watts × load ÷ 1,000)
The last line is the one to look at. Generator power costs several times what your utility charges for a kWh, so the cheapest outage plan is the smallest generator that carries what you need, run only the hours you need it.
Sources: gasoline prices by state from EIA and AAA; propane from the EIA Heating Oil and Propane Update; diesel priced from the EIA heating-oil price plus $0.30/gal (see Notes). Fuel use at 50% load from manufacturer spec sheets (Generac, Champion, Honda, Westinghouse). Prices shown with their state and date: "Price used: $3.20/gal · the US · EIA/AAA, 2025–26 reference (data as of 2026-09-26)".
Worked example
A worked example
A 22,000 W standby generator on propane at half load in Florida burns about 50.4 gallons a day. At the Florida propane price of $3.20/gal, that's $6.72 an hour and $161.28 a day. Each kWh it makes costs about $0.61, roughly 4 times the Florida electricity rate of 15.0¢/kWh.
Reference
By state, at the default inputs
Estimated fuel cost per day, with this page's default inputs and each state's reference prices (EIA reference 2025–26, data as of 2026-09-26).
| US average | $28.80 | 18.4¢/kWh |
|---|---|---|
| Alabama | $26.10 | 15.5¢/kWh |
| Alaska | $34.20 | 25.0¢/kWh |
| Arizona | $31.50 | 15.0¢/kWh |
| Arkansas | $26.10 | 13.0¢/kWh |
| California | $42.30 | 32.0¢/kWh |
| Colorado | $27.90 | 16.0¢/kWh |
| Connecticut | $29.70 | 30.0¢/kWh |
| Delaware | $27.90 | 17.0¢/kWh |
| District of Columbia | $30.60 | 19.0¢/kWh |
| Florida | $27.90 | 15.0¢/kWh |
| Georgia | $27.00 | 14.5¢/kWh |
| Hawaii | $41.40 | 42.0¢/kWh |
| Idaho | $30.60 | 12.0¢/kWh |
| Illinois | $31.50 | 17.0¢/kWh |
| Indiana | $28.80 | 15.5¢/kWh |
| Iowa | $27.00 | 13.5¢/kWh |
| Kansas | $26.10 | 14.5¢/kWh |
| Kentucky | $27.00 | 13.0¢/kWh |
| Louisiana | $25.20 | 12.5¢/kWh |
| Maine | $28.80 | 26.0¢/kWh |
| Maryland | $28.80 | 19.0¢/kWh |
| Massachusetts | $28.80 | 29.0¢/kWh |
| Michigan | $29.70 | 19.5¢/kWh |
| Minnesota | $27.90 | 15.5¢/kWh |
| Mississippi | $25.20 | 13.5¢/kWh |
| Missouri | $26.10 | 13.0¢/kWh |
| Montana | $28.80 | 13.0¢/kWh |
| Nebraska | $27.00 | 12.0¢/kWh |
| Nevada | $35.10 | 15.0¢/kWh |
| New Hampshire | $27.90 | 27.0¢/kWh |
| New Jersey | $27.90 | 22.0¢/kWh |
| New Mexico | $27.00 | 15.0¢/kWh |
| New York | $29.70 | 25.0¢/kWh |
| North Carolina | $27.00 | 14.5¢/kWh |
| North Dakota | $27.00 | 11.5¢/kWh |
| Ohio | $28.80 | 16.5¢/kWh |
| Oklahoma | $25.20 | 13.0¢/kWh |
| Oregon | $35.10 | 14.5¢/kWh |
| Pennsylvania | $30.60 | 18.5¢/kWh |
| Rhode Island | $28.80 | 29.0¢/kWh |
| South Carolina | $26.10 | 15.0¢/kWh |
| South Dakota | $27.00 | 13.0¢/kWh |
| Tennessee | $26.10 | 13.5¢/kWh |
| Texas | $25.20 | 15.5¢/kWh |
| Utah | $30.60 | 12.0¢/kWh |
| Vermont | $28.80 | 22.0¢/kWh |
| Virginia | $27.90 | 15.5¢/kWh |
| Washington | $37.80 | 12.0¢/kWh |
| West Virginia | $28.80 | 15.5¢/kWh |
| Wisconsin | $27.90 | 17.5¢/kWh |
| Wyoming | $27.90 | 12.5¢/kWh |
Questions
FAQ
How much does it cost to run a generator for a week?
Multiply the daily cost by 7. At the US-average gasoline price of $3.20/gal, a 7,500 W generator at half load for 12 hours a day costs an estimated $28.80 a day, about $201.60 for a week. Shorter run blocks cut that in direct proportion.
What's the cheapest fuel for a generator?
It depends on your state's prices and on your generator. With US-average reference prices, a 7,500 W unit at half load for 12 hours comes to about $28.80 a day on gasoline, $37.44 on propane and $19.20 on diesel. Propane costs more per day because the generator burns more gallons of it; it stores for years without going stale.
Is generator power more expensive than grid power?
Yes, several times over. In the US-average example the generator's power costs about $0.64 per kWh, against 18.4¢/kWh from the grid. That's why it pays to run it in blocks instead of around the clock.
Is it worth running a generator to save the food in my fridge?
This calculator gives the fuel side of that decision: a fridge and a freezer on a small generator for a few hours a day costs a few dollars. Compare it with what's in your fridge and freezer. The food side isn't something we can estimate for you.
Why is my cost per kWh so high at light load?
Because the engine burns fuel just to keep turning. At a light load you pay that fixed cost over fewer kWh, so each kWh costs more even though the daily bill is lower.
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