The headline
Sunshine varies a lot across the US, so the number of solar panels it takes to power an EV depends heavily on where you live. We worked it out for all 50 states using the same car, the same driving and the same method.
The headline: most Americans need 7 or 8 panels to cover a year of driving in a Tesla Model Y. That ranges from 5 in Arizona to 11 in Alaska. And even in the cloudiest states, the panels work out to about 4 cents a mile or less.
The big picture
For a 2024 Tesla Model Y Long Range driving 13,500 miles a year (about 3,915 kWh). Costs at $3.00 per watt, the figure our calculator uses, with no tax credit.
| Panels | Cost (no tax credit) | States |
|---|---|---|
| 5–6 | about $6,000–$7,200 | Arizona, California, Colorado, Florida, Hawaii, Nevada, New Mexico, Oklahoma |
| 7 | about $8,400 | Alabama, Arkansas, Delaware, Georgia, Idaho, Iowa, Kansas, Kentucky, Louisiana, Maryland, Massachusetts, Mississippi, Missouri, Montana, Nebraska, North Carolina, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, Wyoming |
| 8 | about $9,600 | Connecticut, Illinois, Indiana, Maine, Michigan, Minnesota, New Hampshire, New Jersey, New York, North Dakota, Ohio, Vermont, West Virginia, Wisconsin |
| 9 | about $10,800 | Oregon, Washington |
| 11 | about $13,200 | Alaska |
What the map tells us
The sunny Southwest and Florida need the fewest panels. Arizona, Nevada and New Mexico get over 6.4 peak sun hours a day.
Half the country sits at 7 panels. That's most of the South, the Plains and the Mid-Atlantic.
The Great Lakes, New York and northern New England need 8.
The Pacific Northwest needs 9, and Alaska 11, because of cloudy winters and short winter days.
How we worked it out
Every state uses the same three steps:
1. The car's yearly energy. The EPA rates the 2024 Tesla Model Y Long Range at about 29 kWh per 100 miles. At 13,500 miles a year, close to the US average, that's about 3,915 kWh.
2. What one panel makes in each state. We took the average peak sun hours for a representative city in each state from The Green Watt's PVWatts v8 table (updated April 2026). Then we applied our usual 18% allowance for system losses. A 400 W panel makes about 770 kWh a year in New Mexico, but only about 380 in Alaska.
3. Divide and round up. Car energy ÷ panel output, rounded up to whole panels. The one exception is Arizona, which needs exactly 5.0 panels' worth, so we counted it as 5.
Costs use $3.00 per watt installed, the same figure as our calculator and close to the national average (SolarReviews reports about $3.03 per watt in October 2026), with no tax credit. Cost per mile spreads that cost over 25 years of driving (13,500 × 25 = 337,500 miles). It doesn't include repairs, an inverter replacement, or panels slowly losing output, which together would add a little.
The full 50-state table
Peak sun hours: The Green Watt, PVWatts v8 data for one representative city per state, south-facing panels at a 20° tilt with no shade. Your own town and roof may differ. "Panels' worth needed" shows the exact figure before rounding up.
| State | Peak sun hours a day | One panel makes (kWh/yr) | Panels' worth needed | 400 W panels | Cost, no tax credit | Cost per mile (25 yrs) |
|---|---|---|---|---|---|---|
| Alabama | 5.21 | 624 | 6.28 | 7 | $8,400 | 2.5¢ |
| Alaska | 3.17 | 380 | 10.32 | 11 | $13,200 | 3.9¢ |
| Arizona | 6.54 | 783 | 5.00 | 5 | $6,000 | 1.8¢ |
| Arkansas | 5.18 | 620 | 6.31 | 7 | $8,400 | 2.5¢ |
| California | 6.08 | 728 | 5.38 | 6 | $7,200 | 2.1¢ |
| Colorado | 5.66 | 678 | 5.78 | 6 | $7,200 | 2.1¢ |
| Connecticut | 4.53 | 542 | 7.22 | 8 | $9,600 | 2.8¢ |
| Delaware | 4.80 | 575 | 6.81 | 7 | $8,400 | 2.5¢ |
| Florida | 5.48 | 656 | 5.97 | 6 | $7,200 | 2.1¢ |
| Georgia | 5.17 | 619 | 6.33 | 7 | $8,400 | 2.5¢ |
| Hawaii | 5.82 | 697 | 5.62 | 6 | $7,200 | 2.1¢ |
| Idaho | 5.22 | 625 | 6.26 | 7 | $8,400 | 2.5¢ |
| Illinois | 4.51 | 540 | 7.25 | 8 | $9,600 | 2.8¢ |
| Indiana | 4.66 | 558 | 7.02 | 8 | $9,600 | 2.8¢ |
| Iowa | 4.75 | 569 | 6.88 | 7 | $8,400 | 2.5¢ |
| Kansas | 5.39 | 645 | 6.07 | 7 | $8,400 | 2.5¢ |
| Kentucky | 4.79 | 573 | 6.83 | 7 | $8,400 | 2.5¢ |
| Louisiana | 5.32 | 637 | 6.15 | 7 | $8,400 | 2.5¢ |
| Maine | 4.55 | 545 | 7.19 | 8 | $9,600 | 2.8¢ |
| Maryland | 4.88 | 584 | 6.70 | 7 | $8,400 | 2.5¢ |
| Massachusetts | 4.70 | 563 | 6.96 | 7 | $8,400 | 2.5¢ |
| Michigan | 4.47 | 535 | 7.32 | 8 | $9,600 | 2.8¢ |
| Minnesota | 4.61 | 552 | 7.09 | 8 | $9,600 | 2.8¢ |
| Mississippi | 5.26 | 630 | 6.22 | 7 | $8,400 | 2.5¢ |
| Missouri | 5.03 | 602 | 6.50 | 7 | $8,400 | 2.5¢ |
| Montana | 4.76 | 570 | 6.87 | 7 | $8,400 | 2.5¢ |
| Nebraska | 4.98 | 596 | 6.57 | 7 | $8,400 | 2.5¢ |
| Nevada | 6.41 | 767 | 5.10 | 6 | $7,200 | 2.1¢ |
| New Hampshire | 4.58 | 548 | 7.14 | 8 | $9,600 | 2.8¢ |
| New Jersey | 4.66 | 558 | 7.02 | 8 | $9,600 | 2.8¢ |
| New Mexico | 6.42 | 769 | 5.09 | 6 | $7,200 | 2.1¢ |
| New York | 4.50 | 539 | 7.27 | 8 | $9,600 | 2.8¢ |
| North Carolina | 5.25 | 629 | 6.23 | 7 | $8,400 | 2.5¢ |
| North Dakota | 4.45 | 533 | 7.35 | 8 | $9,600 | 2.8¢ |
| Ohio | 4.54 | 544 | 7.20 | 8 | $9,600 | 2.8¢ |
| Oklahoma | 5.50 | 658 | 5.95 | 6 | $7,200 | 2.1¢ |
| Oregon | 4.06 | 486 | 8.05 | 9 | $10,800 | 3.2¢ |
| Pennsylvania | 4.79 | 573 | 6.83 | 7 | $8,400 | 2.5¢ |
| Rhode Island | 4.70 | 563 | 6.96 | 7 | $8,400 | 2.5¢ |
| South Carolina | 5.33 | 638 | 6.14 | 7 | $8,400 | 2.5¢ |
| South Dakota | 4.86 | 582 | 6.73 | 7 | $8,400 | 2.5¢ |
| Tennessee | 4.82 | 577 | 6.78 | 7 | $8,400 | 2.5¢ |
| Texas | 5.22 | 625 | 6.26 | 7 | $8,400 | 2.5¢ |
| Utah | 5.39 | 645 | 6.07 | 7 | $8,400 | 2.5¢ |
| Vermont | 4.36 | 522 | 7.50 | 8 | $9,600 | 2.8¢ |
| Virginia | 5.01 | 600 | 6.53 | 7 | $8,400 | 2.5¢ |
| Washington | 3.95 | 473 | 8.28 | 9 | $10,800 | 3.2¢ |
| West Virginia | 4.57 | 547 | 7.16 | 8 | $9,600 | 2.8¢ |
| Wisconsin | 4.58 | 548 | 7.14 | 8 | $9,600 | 2.8¢ |
| Wyoming | 5.36 | 642 | 6.10 | 7 | $8,400 | 2.5¢ |
What changes the answer for your home
Your car: a big electric truck like the Ford F-150 Lightning uses about 48 kWh per 100 miles, so it needs about 1.7 times as many panels as this table shows.
Your driving: the numbers scale with miles. Drive 9,000 miles instead of 13,500, and you need about a third fewer panels.
Shade and roof direction: our numbers assume a south-facing roof with no shade. East- or west-facing roofs, or trees, cut output, so you may need one or two extra panels.
Your town, not your state: big states vary a lot inside. Northern California gets less sun than the desert near Palm Springs, for example. Your installer, or the free PVWatts calculator, can give you a figure for your exact address.
Incentives: the 30% federal tax credit for home solar ended for systems installed after December 31, 2025, but some states and utilities still offer rebates that lower these costs.
An example: Ohio vs New Mexico
Tom lives near Cleveland, Ohio, and Lucia lives in Albuquerque, New Mexico. They drive the same Model Y, 13,500 miles a year each.
Ohio gets about 4.5 peak sun hours a day, so Tom needs 8 panels, costing about $9,600. Albuquerque gets about 6.4, so Lucia needs only 6 panels, about $7,200.
Tom pays about $2,400 more up front. But his panels still work out to just 2.8 cents a mile over 25 years. Compare that with gas: at Ohio's average of about $4.04 a gallon (AAA, October 19, 2026), a 28 MPG car costs about 14.4 cents a mile in fuel. Even in one of the less sunny states, solar charging costs a fraction of gas.
(Tom and Lucia are examples, not real customers. Their savings also depend on how their utilities credit exported solar.)