Solar panels on your camper van: how many do you need?
Solar panels are one of the most popular ways to power your camper van when off-grid. But how many panels do you actually need? That depends on your power consumption, where you travel and in which season. In this guide we help you make the right choice.
Calculate your solar setup
How much power do you use per day?
The first step is calculating your daily power consumption. Add up all the devices you use and estimate how many hours per day they are on.
Typical consumption for a camper van:
• Fridge: 30-50 Ah/day (compressor, depending on outside temperature)
• LED lighting: 2-5 Ah/day
• Phone charging: 2-3 Ah/day
• Laptop charging: 5-8 Ah/day
• Water pump: 1-2 Ah/day
• Diesel heater: 1-3 Ah/day
An average camper van with fridge, lighting and basic electronics uses about 40-70 Ah per day on a 12V system.
How much do solar panels actually produce?
The output of a solar panel depends on three factors: the panel's power rating (in Wp), the number of sun hours and the efficiency of your system.
As a rule of thumb, a 100Wp panel in summer in Southern Europe produces about 5-6 peak sun hours worth of energy, or 500-600 Wh per day (40-50 Ah at 12V). In Northern Europe this is 3-4 peak sun hours in summer and only 1-2 in winter.
Account for losses: the MPPT charge controller loses 5-10%, and heat and cables another 5-10%. So calculate with 70-80% of the theoretical yield.
Fixed, flexible or portable panels?
There are three ways to mount solar panels on your camper van:
Fixed panels (with frame) are the most popular. They are affordable, durable and easy to mount on the roof. Downside: you lose roof space and they don't always face the sun optimally.
Flexible panels are lighter and thinner, ideal when weight is a concern or the roof is curved. They are more expensive and have a shorter lifespan due to higher temperatures (no air circulation underneath).
Portable panels you set up next to the van on the ground. Advantage: you can angle them toward the sun. Downside: you need to set them up and store them each time, and they are vulnerable to theft.
Series or parallel wiring?
With multiple panels you can wire them in series or parallel.
Series: voltage adds up, current stays the same. Advantage: you can use thinner cables and efficiency is higher in partial cloud cover. Downside: if one panel is shaded, the output of all panels drops.
Parallel: current adds up, voltage stays the same. Advantage: shade on one panel doesn't affect the others. Downside: you need thicker cables.
For most camper vans with 2-4 panels on a 12V system, series is the best choice, provided you use an MPPT charge controller.
Calculate your solar setup
Use our free tools to calculate the right number of panels, battery capacity and MPPT charge controller.
Frequently asked questions
- How many solar panels do I need on my camper van?
- This depends on your consumption and travel destination. An average camper van with a fridge and basic electronics needs 200-400Wp (2-4 panels of 100Wp). If you spend a lot of time off-grid in Northern Europe, plan for 400Wp or more.
- Are solar panels enough to power a camper van?
- In summer in Southern Europe, often yes. In winter or bad weather, solar panels alone are usually not enough. Combine them with alternator charging (B2B charger) and/or shore power for a reliable system.
- Do I need an MPPT or PWM charge controller?
- An MPPT charge controller is 20-30% more efficient than a PWM, especially in cloudy weather and with higher panel voltages. For a camper van installation of 200Wp or more, MPPT is almost always the better choice.