Which roof direction is best for solar panels: south, east-west or north?
Short answer
South gives the most energy per panel. East or west roofs produce about 15 to 20% less a year, and a north roof at a typical 30 to 35 degree pitch makes a bit under 60% of a south one. East-west arrays spread generation across the day, which can raise how much you use yourself.
Last checked 24 September 2026 · 2 sources
In more detail
- PVGIS London (14% losses): south 30 deg 1,014; east 30 deg 830 (82%); west 30 deg 805 (79%); north 15 deg 713 (70%); north 30 deg 586 (58%); north 45 deg 461 (45%) kWh/kWp/yr.
- EST: east or west roughly 15-20% less than south; EST does not recommend north-facing roofs.
- Shallow pitches reduce the orientation penalty; steep north roofs are penalised most.
- MCS MGD 003 orientation/pitch tables are the standard for quotes.
The facts, dated
- 01PVGIS London east 30 degrees as share of south 30 — 82 %
market_data · England · checked 24 September 2026 · PVGIS (EU Joint Research Centre)
- 02PVGIS London north 30 degrees as share of south 30 — 58 %
market_data · England · checked 24 September 2026 · PVGIS (EU Joint Research Centre)
- 03EST: east or west gets around 15-20% less energy than south — 15-20 %
installer_view · UK · checked 24 September 2026 · Energy Saving Trust
What we saw in the field
[QA review 2026-09-24] I-4 AGREES at ~30 deg (MCS 57-61%); always state pitch. | Earlier notes: Installer 'north ~60% of south' agrees with PVGIS at 30-35 deg pitch (58%), but is optimistic for steep roofs (45 deg: 45%) and pessimistic for shallow (15 deg: 70%).
Sources
- PVGIS (EU Joint Research Centre) — re.jrc.ec.europa.eu/api/v5_3/PVcalc
- Energy Saving Trust — energysavingtrust.org.uk/advice/solar-panels/
Last checked: 24 September 2026