Best Solar Panel Direction for South West Homes

One of the most common questions during our free site surveys is whether a property's roof direction is "good enough" for solar panels. The short answer is that the vast majority of UK roofs are. South-facing is optimal, but the difference between south, south-east, south-west, and even east or west facing is smaller than most people assume — and with appropriately sized systems, all of these orientations deliver strong financial returns in the South West.

Wiltshire and Somerset receive approximately 980–1,000 kWh of solar irradiance per kWp per year — comfortably above the UK average of around 940 kWh/kWp. This regional advantage means even sub-optimal orientations here outperform ideal orientations in northern England.

An often-overlooked consideration for households in Wiltshire, Somerset, and the wider South West is that south-west facing arrays can actually be more financially valuable than south-facing, despite generating slightly less electricity overall.

Here is why: south-west facing panels generate their peak output in the afternoon and early evening (roughly 13:00–18:00). For households who are at home in the afternoon and evening — retirees, work-from-home households, families after school hours — this timing aligns better with peak electricity demand than a south-facing array peaking at 12:00–13:00. Higher self-consumption means you use more of your solar electricity directly, at 24–28p/kWh, rather than exporting it at the SEG rate of ~10.8p/kWh.

For commuter households (away 09:00–18:00), south or south-east facing arrays are better, as daytime generation will mostly be exported regardless of timing. In this case, battery storage is the more impactful lever for improving financial return — see our battery storage worth it guide for Wiltshire-specific analysis.

Shading is often more impactful on generation than roof orientation. A well-oriented, partially shaded array will frequently underperform a sub-optimally oriented, unshaded one. During our free site surveys, we assess shading from chimneys, dormer windows, trees, neighbouring buildings, and aerial equipment — and model the impact on annual generation for your specific roof.

Where partial shading is unavoidable, we design around it. Sigenergy or Tigo power optimisers on individual panels prevent shading on one panel affecting the output of the entire string — a significant advantage for many Wiltshire properties with Victorian chimney stacks. See our inverter types guide for detail on when optimisers are worth the additional cost.