Tools Spaziou · Solar

Solar panel calculator for camper

Estimate the panel power needed to replace your daily consumption using equivalent peak sun hours and system losses.

White campervan parked in a green valley beneath snow-covered mountains
Actual solar generation depends on the installation and where and how you park.
01 · Consumption

Calculate the energy to replace.

Start solar sizing with the Wh you consume each day.

02 · Useful sun

Think in peak sun hours.

Season, shadows, inclination and temperature change the result a lot.

03 · System

Check the charge controller.

Voltage, current and panel configuration must be compatible.

Peak sun hours ≠ daylight hours

One equivalent peak sun hour represents an hour at reference solar output. The available resource varies with country, season, orientation, tilt, temperature, clouds and shade.

Parking in shade can sharply reduce a camper's solar yield even on a long day.

Next step

Connect solar, battery and consumption.

Calculate consumption →Calculate battery →Solar panel guide →Compare 12 solar panels →Premium panels 350–500 W →Compare MPPT controllers →Electrical planner →All tools →
Save the main inputs, results and notes from this tool or guide.
Solar reference

Actual generation depends on location, month, orientation, temperature, shade and losses. Use a location-specific source to check irradiation and seasonal variation.

European Commission · PVGIS, solar radiation and photovoltaic performance ↗

Method · Example · Decisions

Understand the solar power you need

Panel power in W describes performance under test conditions. Daily energy yield depends on the solar resource and losses across the system.

Formula used in this tool

Indicative power = daily Wh ÷ (peak sun hours × efficiency) × reserve factor. Estimated generation = installed W × peak sun hours × efficiency.

Reproducible example

For 800 Wh/day, 3 peak sun hours, 75% efficiency and a reserve factor of 1.20, the calculation calls for about 427 W. Rounding up in 50 W steps gives 450 W. These sun hours are an entered scenario, not a destination forecast.

Peak sun hours and daylight hours differ

Peak sun hours express energy at a reference irradiance. Ten daylight hours do not mean ten peak sun hours. Adjust location, month, tilt and shade: a horizontal roof panel does not necessarily match a panel aimed by hand.

What is left to check

Check usable roof area, shading from rooflights and racks, string open-circuit voltage, MPPT controller limits and the wiring configuration. The calculator estimates required panel power; it does not establish electrical compatibility between panels and controller.

Does the calculated power guarantee independence?

No. Several cloudy days can leave a deficit even if the monthly average covers demand. The battery provides reserve and the panels recharge it. Compare a conservative scenario and an additional charging source if needed.

European Commission PVGIS: solar resource and simulation by location →

Portable Power · ALLPOWERS

Does your project use a portable power station?

Calculated solar watts guide sizing. Before connecting a panel to a power station, also check cold-weather Voc, current, MPPT voltage range and connector. Matching watt ratings is not enough.

Browse the official ALLPOWERS store ↗View Spaziou's ALLPOWERS selection →
Affiliate links: Spaziou may earn a commission on qualifying purchases at no extra cost to you. Check European version, accessories, price and availability in the store. Selection is based on specifications, not hands-on testing.