You set the sun hours
In north-west Europe three to four effective hours is common in summer, and far fewer in winter.
Calculator
Solar panel calculator for campers and off-grid
Enter your daily consumption and the assumptions you want to use: effective sun hours, system efficiency and the share solar should cover. You get an indicative peak power in Wp.
- Free, no account needed
- 12V, 24V, 48V and 230V
- Result while you type
- Carries over into your diagram
The result is guidance based on your input. Manufacturer instructions and local regulations always take precedence; you remain responsible for the installation.
What this calculator does and does not do
It divides the energy you want from solar each day by the effective sun hours and system efficiency you enter yourself. There is no weather, location or season model behind it: a yield prediction without that data would be invented.
System efficiency
MPPT losses, cabling, temperature and panel orientation together easily take a quarter of the panel power.
Panels and MPPT
Split the resulting Wp across panels that fit your roof; choose the MPPT on that panel power and its voltage.
From calculation to complete diagram
Designing a complete electrical system? In WireElectric you draw the panels, the MPPT, the battery and the loads in one diagram, and the app checks the cabling and protection between them.
You can start drawing without an account.
Open WireElectric
Questions about solar panels
- How many solar panels do I need for my camper?
- That follows from your daily consumption and the sun hours you assume. Enter both and split the resulting peak power across panels that fit your roof.
- Why does WireElectric not show a monthly yield?
- Yield depends on location, season, roof angle and shading. Without that data any number would mislead, so we only use your own assumptions.
- How do I choose the MPPT?
- On the total panel power and the string voltage. In WireElectric you place the MPPT in the diagram and its connections to battery and panels are checked.
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Every calculator answers one question about your installation. WireElectric then runs the same calculations for every connection in your complete diagram.
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View →