How Many Solar Watts Do You Need for Full-Time RV Boondocking?

Weekend boondockers can get away with rough estimates. Full-timers can't. If you're living in your RV off-grid for weeks or months at a stretch, an undersized solar array doesn't just mean an inconvenient cloudy afternoon — it means slowly draining your battery bank day after day until you're forced to break camp early or fire up a generator you were hoping to avoid.

The good news is that sizing solar for full-time boondocking isn't guesswork. It comes down to one number — your actual daily energy use — run through a fairly simple formula. In our Complete RV Solar Power System Guide, we covered how panels, batteries, and power delivery work together as a system. Here, we're zooming in on one piece of that system: exactly how many watts of solar panel you need to support full-time, indefinite off-grid living.

Why "Full-Time" Changes the Math

A weekend trip only has to survive two or three days, so a small buffer of stored battery power can cover any shortfall. Full-time boondocking has to be self-sustaining indefinitely — your solar array has to fully replenish what you use, day after day, through cloudy stretches, shorter winter days, and shaded campsites. That means sizing for your worst realistic week, not your best sunny afternoon.

Step 1: Calculate Your Daily Watt-Hour Usage

Before you can size a solar array, you need to know how much energy you actually use in a day. Walk through your RV and add up the daily watt-hours (Wh) for everything you run:

• 12V refrigerator: roughly 400–700 Wh/day, depending on size and ambient temperature
• Laptop + phone charging: roughly 100–200 Wh/day for a couple of devices
• LED lighting: roughly 50–150 Wh/day depending on how many hours you run lights
• Water pump: roughly 50–100 Wh/day for typical daily use
• Starlink or other satellite internet: roughly 600–900 Wh/day if run continuously
• Vent fans, CPAP machines, or other overnight devices: varies widely — check the wattage label and multiply by hours used

Most full-time boondockers land somewhere between 1,500 and 3,500 Wh of daily use once internet, refrigeration, and basic comforts are accounted for — though heavier loads like induction cooktops or a rooftop AC running part-time can push that number considerably higher.

Step 2: Convert Daily Usage Into Solar Watts

Solar panels are rated in watts, but what actually charges your battery bank depends on how many hours of usable sunlight you get — commonly called "peak sun hours." A location might see 10 hours of daylight but only 4–5 hours of sun strong enough to charge at close to a panel's rated output.

The formula looks like this:

Solar Watts Needed = Daily Watt-Hours ÷ Peak Sun Hours ÷ System Efficiency (~0.8)

For example, a boondocker using 2,400 Wh/day with 4.5 peak sun hours would need roughly:

2,400 ÷ 4.5 ÷ 0.8 ≈ 667 watts of solar

That 0.8 efficiency factor accounts for real-world losses — panel angle, partial shading, wiring resistance, and temperature effects that keep panels from hitting their full rated output in the field. If your usage runs closer to 3,500 Wh/day, that same math pushes you toward 970+ watts. Rather than run these numbers by hand every time your setup changes, our RV Solar Panel Calculator will do this calculation for you based on your actual appliance list and location.

Full-Time Boondocking Wattage Benchmarks

As a starting point before running your own numbers, here's roughly where most full-time boondockers land:

• Lean, minimal-electronics full-timer: 400–600 watts (basic lighting, phone/laptop charging, no continuous internet load)
• Typical full-timer with Starlink and a 12V fridge: 600–900 watts
• Heavier full-timer running an induction cooktop, larger fridge, or partial AC use: 900–1,400+ watts

These numbers assume a reasonably sunny climate and a battery bank sized to match — an undersized battery bank will bottleneck even a well-sized panel array, since there's nowhere for the extra daytime power to go. We go deeper on matching battery capacity to your panel array in an upcoming dedicated battery bank guide for this silo.

Rooftop vs. Portable Panels for Full-Timers

Most full-time boondockers end up running a hybrid setup rather than choosing just one:

Rooftop panels charge automatically while you drive and don't require daily setup — the right baseline for a full-timer who wants reliable passive charging. Rich Solar and Renogy both offer rigid panels well suited to permanent roof mounting, in the wattage ranges above.

Portable panels can be angled directly at the sun or moved into a sunny spot when your rig is parked in shade — a meaningful advantage for full-timers who camp under tree cover more often than not. Bluetti's foldable panel lineup, including the PV120 and PV200, is built specifically for this kind of on-the-go repositioning.

A common full-time strategy: build your baseline wattage into a rooftop array, then add one or two portable panels for shaded campsites or overcast stretches when you need a quick top-up. Our 300-watt and 400-watt panel collections cover the higher end of the full-time benchmarks above, while complete RV solar kits bundle panels with a charge controller for a more turnkey rooftop install. For wiring the array into your existing system safely, our RV Solar Wiring Diagram guide walks through the connection order.

Don't Forget Seasonal and Geographic Swings

Peak sun hours vary significantly by both season and location — a system sized for summer in Arizona will fall short in a Pacific Northwest winter. If you full-time year-round or travel between climates, size your array for your lowest peak-sun-hour location and season you'll realistically spend meaningful time in, not the sunniest stop on your route. For a more precise, location-based peak-sun-hour estimate than a rule of thumb provides, the PVWatts Calculator (National Laboratory of the Rockies) is a free tool worth checking before you finalize your array size.

Quick Reference: Sizing Checklist

1. Add up your realistic daily watt-hour usage, including internet and any heavier appliances
2. Identify your lowest realistic peak-sun-hour scenario, not your best-case one
3. Run the numbers: Watts = Daily Wh ÷ Peak Sun Hours ÷ 0.8
4. Match your battery bank capacity to that same daily usage, with at least a day of reserve
5. Add portable panels as a buffer for shaded or low-sun stretches