What is the Best Angle For Solar Panels?
The best angle for solar panels in the UK is around 35 to 45 degrees facing south. In Liverpool, the European Commission's PVGIS model puts the exact optimum at 41 degrees, but the curve is flat: anything from 30 to 50 degrees comes within a few per cent of the best. Direction matters more than angle, and shading matters more than both. Below are the modelled figures for a typical 4 kWp home system, tilt by tilt and direction by direction.
The short answer
Face south, tilt 35–45°, avoid shade. On a Liverpool roof a 4 kWp south-facing array is modelled at about 3,882 kWh a year at the optimum 41°, and 3,869 kWh at 35°. The pitch your roof already has is almost always close enough, so the panels go on flat to the roof rather than on frames that change the angle.
Tilt: how much the angle actually changes output
PVGIS figures for a 4 kWp south-facing array in Liverpool, with standard system losses:
| Tilt | Modelled output (kWh/yr) | vs the best |
|---|---|---|
| 20° | 3,702 | −4.6% |
| 30° | 3,835 | −1.2% |
| 35° | 3,869 | −0.3% |
| 40°–41° (optimum) | 3,882 | best |
| 45° | 3,873 | −0.2% |
| 50° | 3,842 | −1.0% |
Between 30° and 50° the difference is about one per cent either way. That is why installers rarely fit tilt frames on a pitched roof: the cost and the extra wind loading are not worth a percentage point.
Direction matters more than angle
The same 4 kWp array at 35°, turned to face different directions:
| Facing | Modelled output (kWh/yr) | vs south |
|---|---|---|
| South | 3,869 | — |
| South-west | 3,661 | −5% |
| South-east | 3,601 | −7% |
| West | 3,073 | −21% |
| East | 2,994 | −23% |
| North | 2,041 | −47% |
South-east and south-west roofs lose only five to seven per cent. East and west roofs lose about a fifth, but spread generation into the morning and late afternoon, which can suit a household out during the day. North-facing roofs are rarely worth it.
How the angle compares across Merseyside
Location shifts the total more than a few degrees of tilt. The same 4 kWp south-facing array at 35°, modelled by PVGIS for towns we cover:
| Town | Modelled output (kWh/yr) | vs Liverpool |
|---|---|---|
| Southport | 4,091 | +6% |
| Liverpool | 3,869 | — |
| Birkenhead (Wirral) | 3,848 | −1% |
| St Helens | 3,748 | −3% |
| Warrington | 3,744 | −3% |
The coast does slightly better than inland towns, but every one of them sits within a few per cent of the city. Dropping from the optimum 41° to a shallow 20° costs about 180 kWh a year in Liverpool; picking a north roof over a south one costs about 1,800.
Why the best angle changes through the year
The sun is much higher in summer than in winter, so a steep panel suits December and a shallow one suits June. A fixed home system cannot follow it, so the year-round optimum is a compromise weighted towards the months that generate most. In Liverpool a south-facing 4 kWp array at 35° is modelled at about 506 kWh in May and about 116 kWh in December. Because the summer months dominate the annual total, a few degrees either way barely moves the yearly figure.
East-west terraces
Many Liverpool and Wirral terraces have roofs facing east and west because they follow the street. Panels on both slopes produce about three-quarters of a south-facing array each, but cover the breakfast and teatime peaks rather than midday. With a battery the split matters even less. Our local pages show the modelled figures for solar panels on the Wirral and in Southport, which models the highest output of the towns we have modelled.
Flat roofs and ground mounts
On a flat roof or in a garden the panels go on frames, so you can choose the angle. Steeper is not automatically better here: rows of steeply tilted panels shade each other and catch more wind, so flat roofs often use lower tilts with closer rows, trading a little output per panel for more panels in the space. A ground mount gives full freedom on angle and direction but takes space and may need planning permission, while roof panels on a house are usually permitted development.
Car-park solar canopies are a different case: most are built at 8 to 12 degrees, trading some yield for lower wind loading, as the design guide from Commercial Solar Canopy explains.
Shading beats everything
A chimney, a dormer, a neighbour's gable or a tree can cost more than any angle or direction choice, because on a simple string inverter one shaded panel drags down the whole string. Power optimisers or micro-inverters limit that. That is why a survey measures shading across the day before the layout is fixed. Our solar PV page explains what the survey checks and how the system is sized to your use.
Common questions
What is the best angle for solar panels in the UK?
Around 35 to 45 degrees facing south for most of the UK. In Liverpool, PVGIS puts the optimum at 41 degrees, and anything between 30 and 50 degrees comes within about one per cent of it.
Are east-west solar panels worth it?
Often, yes. In Liverpool an east- or west-facing array is modelled at about 77 to 79 per cent of a south-facing one, and generates in the morning and late afternoon when many households use more electricity.
Should I fit tilt frames to get a better angle?
On a pitched roof, rarely. Most roof pitches are already within a couple of per cent of the optimum, and frames add cost and wind loading. Frames make sense on flat roofs and ground mounts.
Do solar panels work facing north?
They generate, but in Liverpool a north-facing array is modelled at about half the output of a south-facing one, so it is rarely worth it unless there is no other roof.
Updated 15 October 2026
