400 Watt RV Solar Kit: What It Powers and What to Buy

Who a 400 Watt Kit Suits

A 400 watt kit sits in the sweet spot for RVers who camp off hookups on weekends and longer trips but do not run air conditioning from the batteries.

It gives you enough headroom to keep a 12V refrigerator cold, charge laptops and phones, run the water pump, and drive a roof fan, all while the sun tops the bank back up during the day.

If your loads are lighter, a 200 watt kit may be plenty. If you want air conditioning off solar, plan for more.

What a Complete Kit Includes

A complete 400 watt kit is a matched set, which is why it installs more smoothly than parts bought separately.

Which Kit to Buy

A1 SolarStore stocks complete RV solar kits from brands like Renogy and Rich Solar, so you can buy the panels, controller, and wiring as one matched package rather than sourcing each piece.

Based on published specs and user reviews, look for a kit with monocrystalline panels, an MPPT charge controller sized above 400 watts, and clear wiring instructions. Free shipping applies on qualifying orders, and A1 ships from over 60 fulfillment centers (verified May 2026).

Compare the controller brands in our Renogy vs Victron guide and the panels in our best RV solar panels guide.

Battery and Inverter Pairing

Panels decide how fast you recharge, and the battery decides how long you can run without sun, so the two need to match.

For 400 watts of panels, around 200Ah of lithium gives roughly 2,400 watt hours of usable storage, which carries most rigs through the evening and a slow morning. Add a 2,000 watt pure sine inverter if you want household outlets for a laptop or small kitchen gear.

Skimping on either side creates a bottleneck, so keep the panels and battery in proportion as you build.

Realistic Daily Output

In good sun, a 400 watt array commonly produces around 1,200 to 1,600 watt hours a day.

Your real number moves with sun hours, panel angle, shade, and temperature, so plan around the lower end for cloudy stretches and treat the higher end as a bright summer day.

How to Size Up or Down

If you are not sure 400 watts is your number, the honest answer is that it depends on your daily watt hours.

Work through the math in our RV solar system sizing guide, which totals your loads and points you to the right wattage, then come back here to pick the kit.