How many solar panels do I need for an RV?

Most RVs need 800-2,400W of solar (2-6 x 400W panels). Light use (fridge, lights, phone) needs 2 panels. Moderate use adding a laptop, TV, and coffee maker needs 3-4 panels. Heavy use with limited AC run time needs 5-6 panels. The exact count depends on your daily kWh consumption and your location's peak sun hours.

Can I run my RV air conditioner on solar?

Partially. A 13,500 BTU RV AC draws about 1,300W continuously (1,800W startup with a soft starter). Running it for 6 hours consumes 7.8 kWh -- more than most solar systems produce in a day. You can run AC for 2-3 hours during peak sun with a large system (1,600W+ panels, 400+ Ah battery), but full-day AC requires shore power or a generator.

How many solar panels can fit on an RV roof?

Class A motorhomes fit 6-10 panels (200+ sq ft usable roof). Class C motorhomes fit 4-6 panels (100-150 sq ft). Travel trailers fit 3-5 panels (60-120 sq ft). Fifth wheels fit 4-8 panels (80-160 sq ft). Subtract space for AC units, vents, antennas, and skylights -- usable area is typically 50-70% of total roof area.

What is the difference between boondocking and campground solar needs?

At a campground with shore power (30A or 50A hookup), you can run AC, microwave, and everything from the grid -- solar is a bonus. Boondocking (no hookups) means solar and batteries are your only power source, so you need a larger system and more conservative energy management. Most boondockers need 800-1,200W of solar minimum.

Should I use 100W, 200W, or 400W panels on my RV?

400W panels offer the best watts-per-square-foot and lowest cost per watt. A single 400W panel replaces two 200W panels with less roof space, fewer connections, and lower installation complexity. Use 100W or 200W panels only if your roof has irregular shapes or obstructions that prevent fitting larger panels.

How big of a battery bank do I need for RV solar?

For light use (2-3 kWh/day): 200Ah 12V LiFePO4. For moderate use (4-5 kWh/day): 300Ah. For heavy use (6-8 kWh/day): 400-600Ah. Always use LiFePO4 chemistry -- it provides 100% usable capacity vs 50% for AGM, weighs 60% less, and lasts 3,000-5,000 cycles. Size your battery for at least 1.5 days of autonomy without sun.

Do I need an inverter for my RV solar system?

If you want to use standard 120V outlets: yes. A pure sine wave inverter (not modified sine) is required for sensitive electronics like laptops, CPAP machines, and modern refrigerators. Size it for your largest simultaneous AC load. A 2,000-3,000W inverter covers most RV needs including a microwave (1,000-1,200W) and coffee maker (900W), but not both at once.

How Many Solar Panels For An RV? (Calculator + Complete Sizing Guide)

An RV typically uses 3-8 kWh per day depending on whether you run just the basics or add a TV, coffee maker, and limited AC time. At 5 peak sun hours with the PVWatts derate of 0.83, you need 2-6 x 400W panels (800-2,400W). The exact count depends on your RV class, travel style, and whether you boondock or use campground hookups.

The difference between a van and an RV solar system is scale. An RV has more roof space, more appliances, and (usually) higher expectations for comfort. That means more panels, a bigger battery bank, and a beefier charge controller. But the sizing logic is the same: add up your daily energy use, then divide by what your panels produce.

Quick Answer: RV Solar Panel Count

Daily energy use	Usage level	400W panels needed	System size
3 kWh	Light (fridge, lights, phone)	2	800W
5 kWh	Moderate (+ laptop, TV, fan)	3-4	1,200-1,600W
8 kWh	Heavy (+ coffee maker, short AC)	5-6	2,000-2,400W

The math (at 5 PSH):

System watts = daily kWh / (PSH x 0.83) x 1000
Example: 5 kWh / (5 x 0.83) x 1000 = 1,205W = 3 x 400W panels

Try The Calculator

Solar panel wattage

Type any value 10–750 W. Common sizes: 100 W (portable), 400 W (residential 2026), 580 W (commercial).

Peak sun hours per day

hrs

Don't know your PSH? Find your exact value →
Benchmarks: U.S. avg 4.98 · Phoenix 6.54 (highest) · Seattle 3.95 · Anchorage 3.17 (lowest). Above ~5.5 = sunny · 4.5–5.5 = average · below 4.5 = cloudy.

Daily kWh production

0.00kWh

Based on a 400W panel and 5.32 peak sun hours per day

Daily

1.60kWh

average across the year

Monthly

48kWh

× 30 days

Yearly

583kWh

× 365 days

Monthly production for a 400W panel — US Average

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

kWh per month · Source: NREL PVWatts v8

216 kg

CO₂ avoided per year

0.05

equivalent US homes powered

trees planted equivalent

$93

estimated annual savings

Tap to see sensitivity analysisSensitivity analysis

Sensitivity range
Scenario	Value
Low (-20%)	1.3 kWh
Expected	1.6 kWh
High (+20%)	1.9 kWh

Your daily production scales linearly with both panel wattage and peak sun hours. A 10% change in either input changes your result by 10%.

See production for your state Try the system size calculator

RV Appliance Energy Use

Every RV is different, but here are common appliance loads:

Appliance	Watts	Hours/day	Daily Wh
12V compressor fridge	50	12 (cycling)	600
Residential fridge (120V)	150	8 (cycling)	1,200
LED interior lights	40	5	200
Phone + tablet charging	15	3	45
Laptop	60	3	180
TV + streaming device	80	4	320
Roof fan (MaxxAir/Fantastic)	35	8	280
Water pump	60	0.5	30
Coffee maker (drip)	900	0.15 (10 min)	135
Microwave	1,000	0.1 (6 min)	100
13,500 BTU AC	1,300	4	5,200
CPAP machine	30	8	240

A "moderate use" RV with a 12V fridge, lights, laptop, TV, fans, water pump, and a morning coffee pot uses about 1,800-2,200 Wh/day (roughly 2 kWh). Switch to a residential fridge and add longer TV time, and you climb toward 3-4 kWh. AC changes everything -- even 4 hours of air conditioning adds 5+ kWh.

Roof Space By RV Class

Your RV type determines how many panels physically fit:

RV class	Total roof area	Usable area (after AC, vents)	Max 400W panels	Max system
Class A motorhome	250-350 sq ft	150-200 sq ft	6-8	2,400-3,200W
Class C motorhome	150-200 sq ft	80-120 sq ft	3-5	1,200-2,000W
Fifth wheel	150-250 sq ft	80-150 sq ft	3-6	1,200-2,400W
Travel trailer (20-30 ft)	100-180 sq ft	50-100 sq ft	2-4	800-1,600W
Pop-up / teardrop	40-60 sq ft	20-40 sq ft	1-2	400-800W

A standard 400W panel is approximately 21 sq ft (roughly 6.8 ft x 3.4 ft). Measure your roof, subtract AC units, vents, skylights, and antennas, then divide by 22 sq ft (allowing for gaps between panels) to get your maximum panel count.

Boondocking vs Campground: How Usage Changes Sizing

Campground with hookups (30A or 50A): Solar is a supplement, not a necessity. Your shore power handles the AC, microwave, and all heavy loads. A small solar setup (400-800W) keeps the battery topped off during transit days and extends battery life. Many campground-focused RVers skip solar entirely.

Boondocking (no hookups): Solar and batteries are your primary power source. You need to cover 100% of daily use from panels alone (with battery buffer for cloudy days). This is where proper sizing matters:

Boondocking style	Daily kWh	Recommended solar	Battery bank
Minimalist (no AC, 12V fridge)	2-3 kWh	800-1,200W	200Ah LiFePO4
Comfortable (laptop, TV, coffee)	4-5 kWh	1,200-1,600W	300Ah LiFePO4
Full-time (limited AC, all appliances)	6-8 kWh	2,000-2,400W	400-600Ah LiFePO4

For serious boondockers, a generator as backup makes sense. Running a Honda EU2200i for 2 hours puts 3-4 kWh into the battery bank, covering a full cloudy day's deficit. Solar handles 90% of days; the generator handles the rest.

System Components and Sizing

A complete RV solar system includes:

Component	Sizing rule	Recommended	Cost
Solar panels	Cover daily kWh at local PSH	800-2,400W (2-6 x 400W)	$700-$2,000
MPPT charge controller	Panel watts / battery voltage x 1.25	40-60A (Victron, Renogy)	$200-$400
LiFePO4 battery bank	1.5x daily kWh in capacity	200-600Ah 12V	$1,200-$3,600
Pure sine wave inverter	Largest simultaneous AC load x 1.25	2,000-3,000W	$300-$600
DC-DC charger	Match alternator capacity	30-60A	$150-$300
Wiring, fuses, disconnects	Size for max current	2-4 AWG main runs	$150-$300
Mounting and hardware	Roof brackets or tilt mounts	Aluminum Z-brackets	$100-$200
Total			$2,800-$7,400

Charge controller sizing example: A 1,600W panel array on a 12V battery system draws up to 133A at battery voltage. You need at least a 60A MPPT controller, or split the array between two 40A controllers. Many RVers run a 24V or 48V battery system to reduce current and allow smaller wire sizes.

Solar Output By Location

The same system produces very different amounts depending on where you travel:

Region	Avg PSH	1,200W system daily output
Southwest (AZ, NM, NV)	6.0-7.0	6.0-7.0 kWh
Southern plains (TX, OK)	5.5-6.0	5.5-6.0 kWh
Southeast (FL, GA, SC)	5.0-5.5	5.0-5.5 kWh
US average	5.0	5.0 kWh
Pacific NW (WA, OR)	3.5-4.5	3.5-4.5 kWh
Northern winter	2.0-3.0	2.0-3.0 kWh

Daily output = panel watts x PSH x 0.83 / 1000.

Snowbirds who travel south for winter and north for summer enjoy consistently high solar production year-round. If you park in one location year-round, size for the worst month -- not the annual average.

Common Mistakes

Sizing for the brochure, not your life. A 400W panel produces 400W only under perfect lab conditions (STC). In real-world conditions, expect 83% of rated output (the PVWatts derate). A "400W panel" effectively produces 332W peak.

Ignoring the battery bottleneck. Panels are cheap; batteries are expensive. A 2,000W solar array paired with a 100Ah AGM battery (only 600 Wh usable at 50% depth of discharge) is like a fire hose connected to a thimble. The battery fills by 10 AM and the rest of the day's solar production is wasted.

Skipping the DC-DC charger. Even with a large solar system, a DC-DC charger is cheap insurance. Two hours of driving charges 60-100 Ah, which can save you on cloudy days or when parked in shade.

Buying PWM instead of MPPT. PWM controllers waste 25-35% of your panel output. On a 1,200W system, that is 300-400W of panels you paid for but cannot use. An MPPT controller costs $100-$200 more and pays for itself immediately.