Do east-west or north-facing roofs work for solar?
Short answer
East and west roofs work well together, spreading output from early morning to evening, and suit a larger panel-to-inverter ratio. North-facing slopes produce the least and are usually added only as an extra string where other faces are full. The MCS estimate uses separate kWh/kWp values for each orientation and pitch.
Last checked 24 September 2026 · 1 source
In more detail
- MCS azimuth: 0 = south, 90 = east/west, rounded to nearest 5 degrees.
- Kk values derived from PVGIS data multiplied by 0.8 (MIS 3002 Appendix B).
- Each orientation normally needs its own MPPT.
The facts, dated
- 01MCS Kk tables are PVGIS-derived values multiplied by 0.8 — 0.8 multiplier
standard · UK · checked 24 September 2026 · MCS
What we saw in the field
[QA review 2026-09-24] C1-1 AGREES: customer 1's east roof ramped ~8am and west generated until ~8pm in August. I-4 'north ~60% of south' AGREES at ~30 deg pitch per MCS tables (zone 3 595/1014 = 59%; zone 4 616/1082 = 57%), falls to 52-54% at 35 deg and 44-46% at 45 deg. I-3 'east-west can outperform south overall' CONTRADICTS per kWp (E/W 810/1021 = 79% at 35 deg, zone 3); true only for total output where two faces fit more panels. H-2 homeowner's north-east panels 'only help in summer' AGREES (PVGIS 189 kWh June vs 12 kWh December for 1.6 kWp NE).
Sources
Last checked: 24 September 2026