Rules of thumb
Year-round fixed tilt ≈ Latitude
Summer ≈ Latitude − 15°
Winter ≈ Latitude + 15°
These simple rules get you within a few percent of the theoretical best for most sites. Detailed studies find the ideal annual angle is usually a few degrees less than latitude, because more energy arrives in summer.
How much does angle matter?
- Within about 10–15° of the best angle, you lose only a few percent of annual output.
- Flat panels, as on most campervans, lose relatively little in summer but a lot in winter, when the sun is low. At UK latitudes a flat panel can collect roughly half as much as a well-tilted one in mid-winter.
- Steeper winter angles also shed snow and rain better.
Direction
In the northern hemisphere, face panels true south (not magnetic south). East or west facing panels still work, typically giving 80–85% of a south-facing array at moderate tilts, and they spread production across the morning or evening.
Frequently asked questions
What's the best angle for solar panels in the UK?
For year-round output, about 35–40° in southern England and 40–45° in the north and Scotland. A steeper 60–70° is better for winter-focused systems.
Should van solar panels be tilted?
Tilting helps a lot in winter, but most people keep van panels flat for simplicity and security. Portable tilted panels are a good winter add-on.