Motorhome solar panel sizing is about expectations: solar helps top up a leisure battery; it is not magic, especially in a UK winter or under trees. Daily watt-hours depend on season, shade and your array — not the sticker alone.
What this is for
Knowing what changes the harvest before you treat a panel sticker as a daily promise. If the battery still dies overnight, start with the daily power budget, then the Ah label in plain English.
What changes the harvest
- Season and day length
- Panel size and angle (roof layout)
- Shade (trees, buildings, bike racks)
- How clean the panels are
- Charge controller and battery acceptance
What solar cannot fix
A huge inverter load (kettle, heater) can empty a battery faster than a modest roof array can refill it. Fix the budget first, then size solar.
We do not invent daily kilowatt-hours from a panel sticker alone without real conditions. Use the panel and controller datasheets, and check the fitter if the array was added later.
Sources
Panel and controller datasheets, plus the installer. Do not treat a sticker wattage as a UK winter harvest. We don’t invent panel output.