Plug-in solar
Plug-In Solar Angle and Direction: What Works Best in the UK
South at 30 to 40 degrees gives the most from plug-in solar in the UK. What east, west, vertical and flat panels lose, with modelled figures for nine cities.
Key facts
- In London, PVGIS models about 817 kWh a year from 800 W of panels facing south at 40 degrees, the best fixed position, and 808 kWh at 30 degrees.
- The same panels hung vertically facing south give about 594 kWh, roughly 73 percent of the best.
- Vertical panels facing east or west give about 400 to 420 kWh in London, roughly half of the best position.
- The government's July 2026 model gives 690 kWh for 800 W at 30 degrees south and 378 kWh vertical east or west, using average UK sunshine.
- In England, permitted development lets panels on a house wall or balcony project up to 0.4 metres, enough to tilt a landscape panel about 20 degrees out from vertical.
The best position for plug-in solar in the UK is facing south at about 35 to 40 degrees. In London, the European Commission’s PVGIS model puts 800 W of panels there at about 817 kWh a year. South-east or south-west costs about 7 percent, east or west at 30 degrees about a fifth, and vertical on an east or west railing roughly half.
How much each position produces
We modelled 800 W of panels in London with PVGIS, the European Commission’s solar database, using its standard 14 percent system losses and 2005 to 2023 weather data. The figures are yearly kilowatt-hours, with the share of the best position in brackets. East-facing panels give results within a few percent of the west-facing figures shown, and south-east within a few percent of south-west.
| Tilt from horizontal | South | South-west or south-east | West or east | North-west or north-east | North |
|---|---|---|---|---|---|
| 0° (flat) | 676 (83%) | 676 (83%) | 676 (83%) | 676 (83%) | 676 (83%) |
| 15° | 761 (93%) | 730 (89%) | 662 (81%) | 592 (72%) | 567 (69%) |
| 30° | 808 (99%) | 756 (93%) | 640 (78%) | 514 (63%) | 466 (57%) |
| 40° | 817 (100%) | 756 (93%) | 619 (76%) | 467 (57%) | 400 (49%) |
| 50° | 809 (99%) | 740 (91%) | 590 (72%) | 423 (52%) | 336 (41%) |
| 60° | 781 (96%) | 710 (87%) | 553 (68%) | 378 (46%) | 281 (34%) |
| 70° | 736 (90%) | 665 (81%) | 508 (62%) | 332 (41%) | 234 (29%) |
| 90° (vertical) | 594 (73%) | 536 (66%) | 399 (49%) | 242 (30%) | 162 (20%) |
Three things stand out. The best tilt is forgiving: anywhere between about 25 and 50 degrees facing south is within a few percent. Direction matters more than angle once you move away from south. And vertical south-facing panels, the usual position on a south-facing railing, still give nearly three-quarters of the best.
The government’s July 2026 impact assessment, which uses average UK sunshine rather than London’s, gives lower absolute numbers but the same pattern: 690 kWh for 800 W at 30 degrees facing south and 378 kWh vertical facing east or west. It concludes that a 30-degree tilt is “significantly better” than vertical at UK latitudes and that south-facing panels offer greater benefits.
The same positions across Britain
Latitude and local weather move the numbers. PVGIS estimates for 800 W of panels:
| City | 30°, facing south | Vertical, facing south | Vertical, east or west (average) |
|---|---|---|---|
| Plymouth | about 891 kWh | about 636 kWh | about 442 kWh |
| Cardiff | about 827 kWh | about 596 kWh | about 412 kWh |
| London | about 808 kWh | about 594 kWh | about 408 kWh |
| Birmingham | about 768 kWh | about 568 kWh | about 391 kWh |
| Newcastle | about 750 kWh | about 574 kWh | about 379 kWh |
| Edinburgh | about 714 kWh | about 546 kWh | about 361 kWh |
| Aberdeen | about 706 kWh | about 545 kWh | about 351 kWh |
| Manchester | about 704 kWh | about 517 kWh | about 361 kWh |
| Glasgow | about 676 kWh | about 506 kWh | about 346 kWh |
The south-west of England gets about a third more than Glasgow from the same panels. Vertical south-facing panels lose proportionally less in the north, because the sun sits lower in the sky there for more of the year.
Why vertical panels do better in winter
A vertical panel faces the low winter sun almost square on. In the London model, 800 W of panels facing south produced about 27 kWh in December at a 30-degree tilt, about 35 kWh at 60 degrees and about 35 kWh vertically. In June the order reverses: about 100 kWh at 30 degrees, 83 kWh at 60 degrees and 50 kWh vertical.
At midday on the winter solstice the sun is only about 15 degrees above the horizon in London and about 11 degrees in Edinburgh, against about 62 degrees in London in late June. That is also why shade matters most in winter: a building or tree that clears the summer sun can block the winter sun entirely. See plug-in solar in winter for month-by-month figures.
East and west: less in total, better timed
East-facing panels produce in the morning and west-facing panels in the afternoon and early evening. For many homes that matches use better than a sharp midday peak, so less is exported unpaid. The government’s model shows this: its vertical east or west kit sends 72 percent of its output to the home’s own use, against 62 percent for the tilted south-facing kit. As a result, the vertical kit generates about 45 percent less but saves only about a third less, £70 a year against £110.
If your microinverter has two inputs and your space allows, one panel facing east and one west spreads output across the day. The total will be below a south-facing pair, but more of it will be used at home.
Tilting panels on a balcony or wall
The kit’s mounting system decides what is possible. The Interim Product Specification requires the manufacturer to supply the mount, to state the permitted mounting types and installation heights for UK wind and snow loads, and to specify any required angle to the mounting surface for ventilation. Use only an angle the instructions allow; our guide to mounting a panel on a balcony railing compares bracket types.
Planning sets a second limit. In England, permitted development lets panels on a house wall, balcony or roof enclosure project up to 0.4 metres from its plane, or 0.2 metres where it abuts a highway. The government said it raised the limit from 0.2 metres precisely so that panels can be installed at the optimum angle. As rough geometry, a panel mounted landscape, about 1.1 metres tall, tilted about 20 degrees out from vertical projects about 0.38 metres; tilted about 10 degrees, about 0.19 metres. In the London table, moving a south-facing panel from vertical to 70 degrees adds about a quarter to its output. Blocks of flats, Scotland and Wales have different limits; see planning permission for plug-in solar.
On the ground or a flat roof you have more freedom. A frame at 30 to 40 degrees facing south is the best fixed position; check the ballast and wind requirements in the instructions.
Finding your own numbers
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Measure the direction. Stand with your back to the wall or railing and use a phone compass to read the direction you face. Due south is 180 degrees on a compass app.
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Estimate the tilt you can achieve. Vertical on a railing is 90 degrees; check what the kit’s tilting bracket allows and what the projection limit permits.
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Note the shade. Watch the spot at 9am, noon and 4pm, ideally in autumn or winter when shadows are longest.
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Run PVGIS for your address. On the PVGIS website, choose grid-connected PV, enter your total panel watts, 14 percent losses, your slope and an azimuth where 0 is south, -90 is east and 90 is west. It returns yearly and monthly estimates.
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Adjust for shade. PVGIS accounts for hills on the horizon but not for nearby buildings or trees. Reduce the result by the share of the day your panels are shaded.
Mistakes to avoid
- Choosing the panel before the spot. A south-facing patio stand beats a shaded east-facing balcony with twice the panels.
- Over-tilting on a railing. An angle beyond what the manufacturer allows changes the wind load the mount was designed for.
- Ignoring the winter shade. A position in sun all summer can lose its sun for three months.
- Writing off vertical south. It is a good position, and the best one in December.
- Expecting much from north. A north-facing vertical panel produces about a fifth of the best position.
The orientation also changes how much a second panel is worth; see 800 W vs 400 W plug-in solar.
Next steps
Frequently asked questions
What is the best angle for plug-in solar panels in the UK?
For the most electricity over a year, about 35 to 40 degrees from horizontal, facing south. Anything from about 25 to 50 degrees gives within a few percent of the best. Steeper angles of 60 to 70 degrees produce less in summer but more in winter.
Which direction should plug-in solar panels face?
South, if you have the choice. South-east or south-west costs about 7 percent at a 30 to 40 degree tilt. Due east or west costs about a fifth at 30 degrees, and north-facing panels lose so much that they are rarely worth installing.
Is a vertical balcony solar panel worth it?
Facing south, yes: a vertical panel still gives about three-quarters of the best yearly output, and more than a tilted panel in December. Facing east or west, a vertical panel produces about half of the best, which the government's model puts at about £70 a year of savings for 800 W.
Are east-west plug-in solar panels a good idea?
They produce less in total but spread output across the morning and evening, when many homes use more power. The government's model found a higher share of a vertical east or west kit's output used at home, 72 percent against 62 percent for a south-facing tilted kit.
Should I lay plug-in solar panels flat?
Flat panels in London produce about 676 kWh a year per 800 W in the PVGIS model, about 17 percent less than the best tilt, and very little in winter. They also collect dirt and water. A small tilt of 10 to 15 degrees helps both.
Can I tilt panels on a balcony railing in the UK?
Often, with a tilting bracket from the kit's own mounting system. In England, panels on a house balcony may project 0.4 metres, or 0.2 metres if the balcony abuts a highway, and the bracket and angle must be permitted by the manufacturer for your height and wind conditions.
Sources
- PVGIS: Photovoltaic Geographical Information System (version 5.3)
- Plug-in solar final stage impact assessment (16 July 2026), Table 7 and paragraph 35
- Town and Country Planning (General Permitted Development) (England) (Amendment) Order 2026 (SI 2026/896)
- Explanatory Memorandum to SI 2026/896, paragraph 5.7
- Plug-in Solar Device Interim Product Specification, version 2.0, July 2026, section 5.5.1
This guide is general information, not legal, tax or electrical advice. Your utility, state and local code have the final say.