Solar · big loads
How many solar panels to run a heat pump?
A heat pump uses about 35.07 kWh a day, heating in December, the coldest month, in Tennessee’s mixed-humid climate (EIA averages); heat-pump use varies hugely with climate, house size and insulation. On a grid-tied home system that’s about 3,939 kWh a year: 2.67 kW, or 7 × 400 W panels in Tennessee (the middle state for sunshine). Off-grid with a battery it takes about 17,020 W of panels to keep up in December, the worst month, plus a 41,260 Wh battery.
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Can a panel and battery keep it going where you are?
Your situation: powering a heat pump with solar. Different situation?
Your battery and panel
Where and how
By state
Grid-tied covers its yearly use on a home system; off-grid sizes the panels for the worst month (85% charging and 85% inverter losses).
Heat pump: panels in every state
| State | kWh a year | Grid-tied, 400 W panels | Off-grid, worst month |
|---|---|---|---|
| Alabama | 3,939 | 7 | 18,200 W |
| Alaska | 5,688 | 14 | 84,580 W |
| Arizona | 1,270 | 2 | 3,810 W |
| Arkansas | 3,939 | 7 | 13,840 W |
| California | 1,270 | 2 | 3,560 W |
| Colorado | 5,688 | 9 | 13,130 W |
| Connecticut | 5,688 | 10 | 19,500 W |
| Delaware | 3,939 | 7 | 14,510 W |
| District of Columbia | 3,939 | 7 | 14,000 W |
| Florida | 1,712 | 3 | 7,060 W |
| Georgia | 3,939 | 7 | 17,590 W |
| Hawaii | 1,712 | 3 | 4,800 W |
| Idaho | 5,688 | 9 | 23,260 W |
| Illinois | 5,688 | 10 | 21,210 W |
| Indiana | 5,688 | 11 | 21,800 W |
| Iowa | 5,688 | 10 | 20,710 W |
| Kansas | 3,939 | 7 | 11,880 W |
| Kentucky | 3,939 | 7 | 15,400 W |
| Louisiana | 1,712 | 3 | 7,840 W |
| Maine | 5,688 | 11 | 18,030 W |
| Maryland | 3,939 | 7 | 13,900 W |
| Massachusetts | 5,688 | 10 | 18,230 W |
| Michigan | 5,688 | 11 | 22,710 W |
| Minnesota | 5,688 | 11 | 20,290 W |
| Mississippi | 1,712 | 3 | 7,210 W |
| Missouri | 3,939 | 7 | 13,020 W |
| Montana | 5,688 | 10 | 19,170 W |
| Nebraska | 5,688 | 10 | 17,290 W |
| Nevada | 1,270 | 2 | 4,110 W |
| New Hampshire | 5,688 | 10 | 20,830 W |
| New Jersey | 3,939 | 7 | 13,490 W |
| New Mexico | 1,270 | 2 | 3,300 W |
| New York | 3,939 | 7 | 12,700 W |
| North Carolina | 3,939 | 7 | 14,960 W |
| North Dakota | 5,688 | 10 | 23,460 W |
| Ohio | 5,688 | 11 | 23,360 W |
| Oklahoma | 3,939 | 7 | 11,450 W |
| Oregon | 3,831 | 8 | 21,410 W |
| Pennsylvania | 5,688 | 11 | 19,610 W |
| Rhode Island | 5,688 | 10 | 20,590 W |
| South Carolina | 3,939 | 7 | 15,340 W |
| South Dakota | 5,688 | 10 | 17,440 W |
| Tennessee | 3,939 | 7 | 17,020 W |
| Texas | 1,712 | 3 | 6,440 W |
| Utah | 5,688 | 9 | 23,670 W |
| Vermont | 5,688 | 11 | 26,230 W |
| Virginia | 3,939 | 7 | 13,750 W |
| Washington | 3,831 | 8 | 23,010 W |
| West Virginia | 3,939 | 8 | 17,090 W |
| Wisconsin | 5,688 | 11 | 21,730 W |
| Wyoming | 5,688 | 9 | 14,780 W |
Where these figures come from
- Heating energy: EIA RECS 2020 microdata (fetched 2026-11-05), homes heated mainly by an electric heat pump, average kWh a year for space heating by climate: Hot-humid: 1,712 kWh (half 604–2,232, 655 homes); Marine: 3,831 kWh (half 1,206–5,451, 100 homes); Mixed-dry and hot-dry: 1,270 kWh (half 328–1,600, 199 homes); Mixed-humid: 3,939 kWh (half 1,754–5,350, 1146 homes); Very cold and cold: 5,688 kWh (half 1,715–8,178, 272 homes). One source only, reviewed by hand.
- Coldest month: that average × the state’s peak-month share of electric space heating (RECS table CE8.6.M (fetched 2026-11-05)).
- Running watts in cold weather (5 °F): ENERGY STAR certified air-source heat pumps (fetched 2026-11-05), 283,736 certified systems, median 3,284 W (10th–90th percentile 1,565–5,363); generatorist.com chart 4,700 W.
FAQ
How many solar panels to run a heat pump?
A heat pump uses about 35.07 kWh a day, heating in December, the coldest month, in Tennessee’s mixed-humid climate (EIA averages); heat-pump use varies hugely with climate, house size and insulation. On a grid-tied home system that’s about 3,939 kWh a year: 2.67 kW, or 7 × 400 W panels in Tennessee (the middle state for sunshine). Off-grid with a battery it takes about 17,020 W of panels to keep up in December, the worst month, plus a 41,260 Wh battery.
How many kWh does a heat pump use?
About 35.07 kWh a day and 3,939 kWh a year, heating in December, the coldest month, in Tennessee’s mixed-humid climate (EIA averages); heat-pump use varies hugely with climate, house size and insulation. Yours depends on the model and how you use it.
Sources and assumptions
- Solar output (kWh per kW of panels, by month): Global Solar Atlas 2.0, long-term averages to 2025 (data version 2.2.68, updated 2026-04-01), for crystalline-silicon panels facing south at the best fixed tilt, after typical system losses. Data obtained from the “Global Solar Atlas 2.0, a free, web-based application is developed and operated by the company Solargis s.r.o. on behalf of the World Bank Group, utilizing Solargis data, with funding provided by the Energy Sector Management Assistance Program (ESMAP). For additional information: https://globalsolaratlas.info” Licensed CC BY 4.0; we rounded and combined it as described here. Not affiliated with or endorsed by Solargis or the World Bank Group.
- State figure: population-weighted average of the state’s three largest cities (U.S. Census Bureau Vintage 2024 population estimates; coordinates from the 2020 Census Gazetteer). Hawaii and DC use one city.
- Cross-check: NASA POWER sunshine climatology (2001–2025), tilted with a standard isotropic-sky model × 0.80. States more than 12% apart were reviewed by hand; the gaps are explained on our methodology page.
- Home use: EIA Table 5A, 2024 average monthly residential kWh by state. Rates: EIA Electric Power Monthly, August 2026.
- Tax credit: IRS FAQ on the One, Big, Beautiful Bill (FS-2025-05, Aug. 21, 2025).
- Assumptions: 85% charging efficiency into a battery, 85% from battery to appliance, panel counts rounded up, off-grid sizing for the worst month.