North facing balcony solar panels still generate electricity, but not much of it. Modelled in PVGIS, an 800 Wp array hung vertically on a north-facing railing in London makes around 161 kWh a year. That’s about 27% of what the same panels produce on a south-facing railing, and about a fifth of what they’d produce tilted at 35 degrees towards the sun.
Those are modelled figures rather than measurements, so the method matters as much as the number and this page sets out how they were produced. Our general orientation guide covers all eight compass points across a range of tilts. This one goes deeper on the case it treats in a paragraph: a flat whose only usable aspect points away from the sun.
The short version
A vertically mounted array facing due north in the UK produces roughly a quarter to a third of what the same array produces facing south, and around 60% of its whole year’s output arrives between May and August. Almost all of it is ambient light scattered by cloud and sky rather than direct sunlight, which is why the figure barely changes between London and Edinburgh. The angle you can fix the panel at does far more for the output than the compass direction does.
How these numbers were worked out
Every output figure here comes from PVGIS, the photovoltaic performance tool published by the European Commission’s Joint Research Centre, queried through its version 5.3 API in August 2026. We ran it rather than copying anyone else’s table. The inputs, so you can reproduce them:
| Parameter | Value used |
|---|---|
| Radiation database | PVGIS-SARAH3, satellite-derived, 2005 to 2023. Our city-by-city output table uses the older PVGIS-SARAH2 (2005 to 2020), which runs about 1% higher, so the same orientation reads a few kWh above these figures there. |
| Meteorological database | ERA5 |
| Peak power | 0.8 kWp of crystalline silicon |
| System loss | 14% (the PVGIS default) |
| Mounting | Fixed, free-standing |
| Horizon | DEM-calculated |
| Azimuth | 0 for south, ±90 for west and east, 180 for north |
| Slope | 90 degrees for a railing mount, 35 degrees for the tilted comparison |
An 800 Wp array is a fair stand-in for a two-panel plug-in kit at roughly 400 W per panel. It sits under the 2,000 W DC cap and under the 960 W threshold at which a manufacturer must advise you to consider a professional assessment of your wiring.
Four things the model can’t see, all of which push the real number down. The horizon data covers terrain rather than buildings, so it knows nothing about the block opposite or the slab overhead. It doesn’t know your balustrade, and a solid parapet cuts off the low sky a vertical panel depends on. It assumes air behind the module, so one clamped against a railing runs hotter. And the 14% loss allowance is generic, not a measurement of any kit.
Treat what follows as an optimistic ceiling rather than a real-world forecast. For a figure with your own postcode in it, our savings calculator runs the same kind of estimate.
What a north balcony produces
Vertical mounting, 800 Wp, London, kWh per year:
| Direction | Annual output | Share of due south |
|---|---|---|
| South | 594 kWh | 100% |
| South-east | 559 kWh | 94% |
| South-west | 536 kWh | 90% |
| East | 416 kWh | 70% |
| West | 399 kWh | 67% |
| North-east | 249 kWh | 42% |
| North-west | 242 kWh | 41% |
| North | 161 kWh | 27% |
Run the same query at 35 degrees of tilt and north climbs to 432 kWh, or 53% of south. That’s the number most direction tables quote, and it’s why north looks less bleak in general solar advice than it does on a balcony. An array pointed north makes less electricity than the same array pointed south, and how much electricity it gives up depends almost entirely on the angle: nearly three quarters at vertical, under half at 35 degrees. Tilted panels see far more sky. A vertical one facing north sees almost none of the sun’s actual path.
The figure is also unusually insensitive to where you live. North facing solar panels generate as much in Edinburgh as in London, near enough: 150 kWh against 161 kWh, with Birmingham at 161 and Manchester at 155. A south-facing vertical array over the same four locations spans 517 to 594 kWh. Latitude matters much less when the light arriving is scattered rather than direct, which is exactly the situation a north wall is in.
Roof advice doesn’t transfer to a balcony
Most of what’s written about installing solar panels in the UK assumes a homeowner with a roof, and those numbers don’t carry across.
A north-facing roof is pitched, usually somewhere between 30 and 45 degrees. That slope still points a good share of the panel at open sky, which is why rooftop guidance often quotes half of a south-facing roof and means it. Solar panels on a balcony railing sit at 90 degrees. Same bearing, very different surface, and the gap between 53% and 27% in our own modelling is the whole of that difference.
The commercial picture differs too. A roof needs an installer, usually scaffolding, and a fixed solar installation that stays with the building. A plug-in kit is bought off a shelf and taken with you when you move. Roof space isn’t the constraint on a balcony, and nor is the price of solar PV hardware. The angle is. So when you see a cheerful figure for solar panels on a north-facing roof, check what tilt it assumes before applying it to a railing.
Why it isn’t zero, and why nearly all of it lands in summer
A vertical surface facing due north in the UK can only see the sun directly when the sun’s bearing is north of due east or due west. Using the standard sunrise azimuth relationship, cos A = sin δ / cos φ, that happens only between the spring and autumn equinoxes. At the summer solstice in London the sun rises at a bearing of about 50 degrees and sets at about 310, leaving roughly seven hours a day when it’s on the northern side of the sky. At the equinoxes that window closes to nothing, and from late September to late March a north wall gets no direct beam at all. At midday, all year, the sun is behind the building.
Seven hours sounds generous until you remember the geometry: the sun is low whenever it’s north of the east-west line, and the panels receive it at a glancing angle. What keeps output above zero for the rest of the year is diffuse radiation, the solar energy scattered by cloud and sky that arrives from every direction at once. On cloudy days the sky is close to uniform and every aspect converges, so a north panel is less exposed to a bad summer than a south one. PVGIS puts the year-to-year variation at 3.7 kWh on the north figure against 28.3 kWh on the south, which is about 2% of output against 5%.
The monthly split makes the seasonality obvious. Same London array, kWh per month:
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| North | 3.1 | 5.3 | 10.9 | 16.3 | 24.3 | 27.9 | 27.4 | 19.5 | 12.7 | 7.6 | 3.7 | 2.4 |
| South | 36.9 | 42.2 | 56.8 | 61.5 | 53.4 | 50.4 | 52.5 | 54.7 | 58.0 | 50.8 | 42.5 | 34.6 |
Around 62% of the north array’s year arrives in the four months from May to August, against 35% for the south array. December is the figure worth staring at: 2.4 kWh for the whole month, under 80 Wh a day. The south-facing panels manage 34.6 kWh in the same month, because a vertical surface is close to ideal for the low winter sun. Our guide to balcony solar in winter has the wider picture, but the honest summary for a north balcony is that it contributes almost nothing between November and February.
East and west: what they actually deliver
If your balcony faces east or west rather than north, the picture changes completely. On the same vertical mounting, London models at 416 kWh east and 399 kWh west, which is 70% and 67% of due south. Those are workable numbers for a plug-in kit.
East came out ahead of west in all four locations we modelled, and south-east ahead of south-west in all four as well. The margin is 4 to 5%, inside the noise of anything you could measure on a real balcony, so we wouldn’t read much into it. North-east and north-west came out within about 3% of each other, and Edinburgh was the one location of the four where north-west edged ahead.
Raw kilowatt-hours aren’t the whole story. What a unit is worth depends on self-consumption: electricity generated while nobody’s home is exported, and without a Smart Export Guarantee (SEG) arrangement with your energy supplier, exported units earn nothing. A west facing array pushes its generation into the late afternoon and evening, when households are actually using power and when time-of-use tariffs charge the most. East front-loads into the morning. So west can be worth more per kWh even where it produces slightly fewer of them.
North-east and north-west sit well above due north
At 242 to 249 kWh in London, the two northern diagonals produce about half again as much as due north, because rotating 45 degrees off north buys back a slice of the summer morning or evening sun.
So pin down your actual bearing before writing anything off, and take several readings, because phone compasses drift near metal railings and reinforced concrete. A bearing of 30 degrees is a different proposition from zero.
Tilt is a bigger lever than the compass here
This is the part general direction advice skips, and on a north balcony it’s the single most useful thing to know. Holding the bearing at due north and varying only the angle, London models like this:
| Slope | Annual output | Versus vertical |
|---|---|---|
| 0° (flat) | 676 kWh | 4.2× |
| 20° | 534 kWh | 3.3× |
| 30° | 466 kWh | 2.9× |
| 40° | 399 kWh | 2.5× |
| 60° | 281 kWh | 1.7× |
| 75° | 214 kWh | 1.3× |
| 90° (vertical) | 161 kWh | 1.0× |
Laying the same panels nearly flat produces over four times what hanging them off the north railing does. At zero degrees the compass direction stops being a variable at all, and we checked that: PVGIS returns 676 kWh at zero slope whether you tell it south, east or north.
So if you want to maximise a north balcony, the useful question is whether you can get the panel off the vertical at all, rather than which way to point it. A low-angle floor frame, a module propped on the floor leaning back against the balustrade, or a bracket that tilts the top edge outward all recover far more than any fiddling with the bearing.
Three cautions before you lay panels flat. A flat panel on a balcony floor is the most likely thing there to sit in the shade of the slab above, and the table assumes a clear sky view it won’t have. It catches wind differently and needs securing properly. And it eats floor space a railing mount doesn’t. Our mounting guide covers the hardware. If you have a Juliet balcony none of this is open to you, because there’s no floor to work with and the panel is stuck at 90 degrees.
When a north balcony genuinely isn’t worth it
Whether it’s actually worth the outlay comes down to setting the annual output against the upfront cost. Assume every kilowatt-hour displaces electricity you’d otherwise have bought, which is generous but roughly true here, since 161 kWh spread across a year rarely exceeds what a flat is drawing anyway.
| Your unit rate | Annual value of 161 kWh | Years to cover £400 | Years to cover £600 |
|---|---|---|---|
| 20p/kWh | £32 | 12.4 | 18.6 |
| 25p/kWh | £40 | 9.9 | 14.9 |
| 30p/kWh | £48 | 8.3 | 12.4 |
The £400 to £600 range is DESNZ’s own expected retail pricing for a kit, with a modelling mean of £500. What you could save off your electricity bills depends on the electricity prices you’re actually paying, and on that arithmetic a north-facing system sits somewhere between eight and nineteen years from paying for itself, before any mounting hardware, electrical work or panel degradation. The government’s headline estimate of £70 to £110 a year models a 30 degree installation facing south at the top end, and a north railing isn’t in that conversation.
There’s a second cost that’s easy to miss. G98 Issue 2 Amendment 1 2026 restricts you to one device per household, whatever the specification says about circuits. So if your flat also has a south or west-facing window, wall or yard, the one device you’re permitted should go there. Putting it on the north balcony spends the whole household allowance on your worst surface.
It stops making financial sense, in our view, when all of these are true at once: the bearing is within about 20 degrees of due north, you can’t get the slope below roughly 60 degrees, the balcony is overshadowed by the slab above or a facing block, and a better aspect exists somewhere on the property.
Before you write off a north balcony
Check whether another surface on the same property is available. A south facing or west-facing exterior wall, a window recess, a shared yard or a ground-floor patio can all take a panel where a north railing can’t do much with one. Permission and cable routing both need sorting, and drilling into anything you don’t own means asking first, but the difference between a north railing and a west wall is roughly two and a half times.
If none of that applies, a north balcony isn’t automatically pointless. It’s a small, predictable trickle of renewable generation with a long payback, and some households will take that on its own terms. What we’d push back on is any product listing implying reduced generation of this order performs like a conventional installation.
The rules don’t care which way you face
Which way your panels point has no bearing on whether a device is compliant. From 27 August 2026 a compliant plug-and-play device can lawfully be sold and used in Great Britain, and every gate is a property of the product rather than the aspect: a verified ENA Type Test Register listing, an on-product compliance declaration, a BS 1363 plug with a 5 A fuse going into an ordinary socket, and mandatory notification to your network operator. Our summary of what actually changes on 27 August sets out the full list.
Two things bite when you move a panel to a better aspect. Clause 5.8 of the Interim Product Specification prohibits installation on timber balconies, on ACM, MCM or HPL cladding systems, and on buildings under external wall fire safety remediation. That’s a prohibition rather than a caution, and no landlord or freeholder can sign it away. And fixing anything to an external wall is a different permission question from resting a frame on your own floor, so every renter should read our guide to asking your landlord before buying hardware.
Frequently asked questions
Do north-facing solar panels work in the UK? They work, they just don’t work well. Our PVGIS modelling puts an 800 Wp array on a vertical north-facing railing in London at about 161 kWh a year, against 594 kWh facing south. Most of that is ambient light rather than direct beam, because a north wall only sees the sun near sunrise and sunset in summer.
How much power do north-facing panels lose against south-facing panels? On a vertical balcony railing, roughly 73%. Tilt the solar panel system to 35 degrees and the gap narrows to about 47%, because a tilted panel sees much more sky. That’s why advice written for a north-facing roof gives a more forgiving number than a balcony deserves.
Is a north-facing balcony system worth getting? On payback alone, usually not. At a kit price of £400 to £600 the modelled output takes between eight and nineteen years to pay back, depending on your unit rate. It’s harder still to justify if you have any better aspect available, because the one device per household limit means you only get one attempt.
What is the 33% rule for solar panels? It isn’t a UK rule and it isn’t about direction. The phrase turns up in mostly US-facing content in two unrelated senses, one about how much of a roof area an array may cover before fire access setbacks apply, and one about oversizing panels relative to inverter capacity. We haven’t found it in any UK standard or in the plug-in solar specification, so we wouldn’t use it to judge a balcony.
Would battery storage make a north balcony worth it? It wouldn’t change the generation, and battery-integrated devices can’t use the plug-in route anyway. That exclusion is statutory rather than a clause in the specification. At 161 kWh a year there’s very little surplus to store, since a solar system producing that little is usually consumed as it arrives.
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