Should I choose east-west over south if available?

If you have BOTH south AND east-west options: south gives maximum total kWh. If you ONLY have east or west: go for it — 80% of south output at the same cost per panel. If you work away and want maximum self-consumption without a battery: east-west split is financially optimal.

What about north-facing?

North-facing is genuinely poor: 55-65% of south output at UK latitudes. Not recommended unless no other option exists. Even then, a north-facing system at 60% output can still deliver 70-90%+ ROI over 25 years — just with a longer payback.

Does this apply to the whole UK?

The orientation effect is consistent across the UK. At higher latitudes (Scotland), the east-west penalty is slightly larger (75-80% vs 80-85% in southern England) because the sun stays lower in the sky. But the principle holds everywhere.

Why do installers still recommend south-first?

Because south maximises total kWh output — which looks impressive on quotes. But total kWh is not the same as financial return. A more sophisticated analysis considers self-consumption patterns, which favour east-west for many household types.

The South-Facing Myth: Data

By Home Solar Guide Team|Updated 20 October 2026|educational

Independently written | Plain-English guide

South-facing myth debunked — PVGIS data: east/west produces 80-90% of south. Self-consumption is often BETTER.

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Find the right system size for your roof

Panel count depends on your electricity use, roof space and direction — not on a rule of thumb. Get a recommended size and what it should cost.

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Do solar panels have to face south?

The south-facing myth is the most widely repeated piece of solar advice — and it's misleading. PVGIS DATA FOR LONDON (re.jrc.ec.europa.eu): Due South (180°): 1,020 kWh/kWp/yr (100% baseline). South-East (135°): 970 kWh/kWp/yr (95%). South-West (225°): 970 kWh/kWp/yr (95%). East (90°): 820 kWh/kWp/yr (80%). West (270°): 830 kWh/kWp/yr (81%). THE COUNTER-INTUITIVE FINDING: A 4kW east-west SPLIT system (2kW east + 2kW west) produces less total kWh than 4kW south BUT achieves HIGHER self-consumption — because it generates morning (east) AND evening (west) when households are active, rather than peaking at midday when many homes are empty. Financial return from self-consumed kWh (26.32p) is 5-6x higher than exported kWh (4.5p). For a working couple: east-west split can deliver BETTER financial returns than south-only despite lower total generation. Sources: PVGIS solar radiation database, European Commission Joint Research Centre (re.jrc.ec.europa.eu/pvg_tools/en/). All orientation data for London coordinates (51.5°N, 0.1°W) at 35° tilt.