Guide
How many solar panels for a van or RV?
Updated October 22, 2026. Prices checked on the makers' own sites that day.
The short answer
A typical van uses 700 to 1,800 Wh a day. In June, 400 W of flat roof solar makes about 1,590 to 2,390 Wh a day depending on the state, which covers most vans. In December the same panels make about 260 to 990 Wh, so plan on a DC-DC charger and some driving, or shore power.
What one watt of flat panel makes per day
Watt-hours per watt of panel per day, for a panel lying flat on a roof, in each state's reference city. Multiply by your panel watts to get daily watt-hours. For example, 400 W in Phoenix makes about 1022 Wh a day in December and 2505 Wh in June.
| State (city) | Dec | Mar | Jun | Sep | Year avg |
|---|---|---|---|---|---|
| Alabama (Birmingham) | 2.04 | 3.77 | 4.84 | 3.70 | 3.61 |
| Alaska (Anchorage) | 0.10 | 2.16 | 4.57 | 1.97 | 2.13 |
| Arizona (Phoenix) | 2.55 | 4.58 | 6.26 | 4.63 | 4.56 |
| Arkansas (Little Rock) | 1.86 | 3.51 | 5.03 | 3.80 | 3.54 |
| California (Los Angeles) | 2.29 | 4.34 | 6.28 | 4.69 | 4.51 |
| Colorado (Denver) | 1.91 | 3.92 | 5.33 | 4.41 | 4.01 |
| Connecticut (Bridgeport) | 1.36 | 3.21 | 4.65 | 3.39 | 3.22 |
| Delaware (Wilmington) | 1.59 | 3.38 | 5.03 | 3.49 | 3.38 |
| District of Columbia (Washington) | 1.70 | 3.45 | 4.86 | 3.42 | 3.36 |
| Florida (Jacksonville) | 2.32 | 3.93 | 4.99 | 3.49 | 3.79 |
| Georgia (Atlanta) | 2.00 | 3.69 | 4.74 | 3.57 | 3.53 |
| Hawaii (Honolulu) | 3.39 | 4.76 | 6.06 | 5.33 | 4.76 |
| Idaho (Boise) | 1.10 | 3.27 | 5.69 | 3.93 | 3.57 |
| Illinois (Chicago) | 1.13 | 3.14 | 5.13 | 3.57 | 3.26 |
| Indiana (Indianapolis) | 1.28 | 3.11 | 4.86 | 3.54 | 3.26 |
| Iowa (Des Moines) | 1.33 | 3.41 | 5.15 | 3.78 | 3.44 |
| Kansas (Wichita) | 1.90 | 3.88 | 5.27 | 4.23 | 3.85 |
| Kentucky (Louisville) | 1.43 | 3.20 | 4.74 | 3.56 | 3.26 |
| Louisiana (New Orleans) | 2.48 | 3.95 | 4.69 | 4.05 | 3.73 |
| Maine (Portland) | 1.25 | 3.23 | 4.40 | 3.41 | 3.14 |
| Maryland (Baltimore) | 1.57 | 3.40 | 5.02 | 3.45 | 3.38 |
| Massachusetts (Boston) | 1.41 | 3.24 | 4.51 | 3.22 | 3.15 |
| Michigan (Detroit) | 0.94 | 2.86 | 4.82 | 3.18 | 3.03 |
| Minnesota (Minneapolis) | 1.05 | 3.42 | 4.92 | 3.57 | 3.19 |
| Mississippi (Jackson) | 2.23 | 3.63 | 5.06 | 3.96 | 3.70 |
| Missouri (Kansas City) | 1.55 | 3.37 | 5.32 | 4.00 | 3.57 |
| Montana (Billings) | 1.27 | 3.30 | 5.18 | 3.71 | 3.37 |
| Nebraska (Omaha) | 1.41 | 3.40 | 5.23 | 3.88 | 3.51 |
| Nevada (Las Vegas) | 2.35 | 4.29 | 6.14 | 4.48 | 4.38 |
| New Hampshire (Manchester) | 1.39 | 3.22 | 4.50 | 3.19 | 3.13 |
| New Jersey (Newark) | 1.43 | 3.25 | 4.75 | 3.37 | 3.22 |
| New Mexico (Albuquerque) | 2.61 | 4.29 | 5.64 | 4.59 | 4.42 |
| New York (New York City) | 1.44 | 3.29 | 4.85 | 3.43 | 3.28 |
| North Carolina (Charlotte) | 1.96 | 3.67 | 4.79 | 3.63 | 3.56 |
| North Dakota (Fargo) | 0.96 | 3.80 | 5.26 | 3.44 | 3.24 |
| Ohio (Columbus) | 1.35 | 3.23 | 4.83 | 3.50 | 3.25 |
| Oklahoma (Oklahoma City) | 2.12 | 3.80 | 5.36 | 4.34 | 3.90 |
| Oregon (Portland) | 0.79 | 2.62 | 5.10 | 3.41 | 3.05 |
| Pennsylvania (Philadelphia) | 1.58 | 3.37 | 5.04 | 3.48 | 3.37 |
| Rhode Island (Providence) | 1.42 | 3.41 | 4.97 | 3.35 | 3.30 |
| South Carolina (Charleston) | 2.15 | 3.89 | 5.06 | 3.61 | 3.77 |
| South Dakota (Sioux Falls) | 1.28 | 3.67 | 5.04 | 3.78 | 3.43 |
| Tennessee (Nashville) | 1.72 | 3.55 | 4.99 | 3.73 | 3.46 |
| Texas (Houston) | 2.35 | 3.55 | 5.13 | 4.07 | 3.67 |
| Utah (Salt Lake City) | 1.66 | 3.84 | 5.85 | 4.31 | 3.93 |
| Vermont (Burlington) | 0.97 | 2.88 | 4.19 | 3.18 | 2.88 |
| Virginia (Virginia Beach) | 1.99 | 3.59 | 5.24 | 3.63 | 3.59 |
| Washington (Seattle) | 0.69 | 2.54 | 4.70 | 3.27 | 2.88 |
| West Virginia (Charleston) | 1.48 | 3.25 | 4.76 | 3.47 | 3.20 |
| Wisconsin (Milwaukee) | 0.99 | 3.01 | 4.80 | 3.42 | 3.07 |
| Wyoming (Cheyenne) | 1.83 | 3.81 | 5.42 | 4.26 | 3.83 |
Solar you'd need for 1,000 Wh a day
With a lithium battery (95% charging efficiency), rounded up to the next 100 W:
| December | March | June | September | |
|---|---|---|---|---|
| Arizona | 500 W | 300 W | 200 W | 300 W |
| Colorado | 600 W | 300 W | 200 W | 300 W |
| Florida | 500 W | 300 W | 300 W | 400 W |
| Washington | 1,600 W | 500 W | 300 W | 400 W |
| Minnesota | 1,100 W | 400 W | 300 W | 300 W |
Most van roofs fit 400 to 600 W of rigid panels around a roof fan. That is why the planner asks for your roof limit and adds the alternator's share before it sizes solar: in December in Washington, one hour of driving with a 40 A DC-DC charger puts back about 486 Wh, while 400 W of flat panel makes about 264 Wh all day.
Pick panels
Disclosure: We may earn a commission if you buy through these links. It never changes what we recommend or what the tools calculate. How we make money.
Roof, lowest cost per watt
Renogy 200W N-Type Bifacial Panel
A rigid 200 W panel; the lowest price per watt among the panels we checked.
$1.00 per watt
No roof holes
Bluetti SP200L Portable Panel
A folding 200 W panel you set out in the sun beside the rig: no roof holes.
$2.00 per watt; aim it at the sun
Curved roofs only
Bluetti PV100 FX Flexible Panel
A 100 W flexible panel for curved roofs where rigid panels won't sit flat. Costs about three times as much per watt as a rigid panel.
$3.29 per watt
How we got these numbers
We ran the PVWatts v8 solar model (the engine behind the National Laboratory of the Rockies', formerly NREL's, PVWatts calculator) on hourly NASA POWER weather for 2022 to 2024, with the panel flat (0° tilt), PVWatts' standard 14% system losses for heat, dirt, wiring and mismatch, and DC output, which is what an MPPT controller passes to the battery. One reference city per state: the mountains, the coast and the desert in the same state can differ.
Places like Arizona make it look easy. Places like Washington in winter don't, and no amount of roof will fix that; driving and shore power will.
Run the power planner
Battery, solar, charger, inverter, every wire and fuse, and a priced parts list.
Draw your wiring
Drag parts onto a diagram and get gauge and fuse labels on every run.
Questions people ask
How many solar panels do I need for a van?
Divide your daily watt-hours by what one watt of panel makes per day where and when you camp. A van using 1,000 Wh a day needs about 200 W in Arizona in June but about 600 W in Colorado in December, about all a van roof holds. That's why most vans pair 400 to 600 W of solar with a DC-DC charger.
Is 200 W of solar enough for a van?
For a fridge, fan, lights and phones (about 700 Wh a day) in summer in the sunny half of the country, often yes. In winter or in the north, no: in Colorado in December 200 W of flat panel makes about 362 Wh a day.
What are peak sun hours?
The number of hours of full, standard-strength sun a day's light adds up to. Our table goes one step further: it's the watt-hours one watt of flat panel delivers to the battery side per day after heat, dirt and wiring losses, which is the number you actually need.
Rigid, flexible or portable panels?
Rigid panels cost least per watt (Renogy 200W N-Type Bifacial Panel: $1.00 per watt) and last longest. Flexible panels fit curved roofs but cost far more per watt (Bluetti PV100 FX Flexible Panel: $3.29) and run hotter. A portable panel you aim at the sun beats a flat roof panel of the same size, especially in winter, and needs no holes.
Sources
Keep going
Van electrical basics
The six parts every camper system has, how they connect, and a diagram to download.
DC-DC charger sizing
20 A or 40 A, smart alternators, and what an hour of driving puts back.
Best lithium battery for a van
Redodo and LiTime batteries by price per usable watt-hour, BMS current and cold-weather charging.
Power station vs built-in
When a Bluetti box beats a wired system, and when it costs you more.