No, you do not need a south-facing roof to make solar worthwhile. East and west-facing roofs are absolutely viable for UK solar — and for households that are out during the middle of the day, an east-west split can actually save you more money than a south-facing system would.
This guide cuts through the confusion. We'll look at exactly how much less an east-west roof generates, why the timing of that generation often matters more than the total, and the situations where it genuinely isn't worth doing.
Do solar panels work on an east or west-facing roof?
Yes — clearly and firmly. The Energy Saving Trust is unambiguous on this: east and west-facing roofs still work, and they note the only orientation they don't recommend is north-facing. The myth that you need a south-facing roof comes from a time when panel efficiency was lower and the economics were tighter. Modern high-efficiency panels have changed that picture considerably.
The direction your roof faces affects how much your system generates. It doesn't determine whether solar is worth installing.
How much less do east-west solar panels generate?
The Energy Saving Trust puts it plainly: a system facing east or west tends to get around 15–20% less energy annually than one facing directly south. That's the honest number, and it's smaller than most people assume.
To put it in practical terms: if a 4kWp south-facing system on a typical UK roof might generate around 3,500–3,800 kWh a year, the same system on an east or west-facing roof would typically produce roughly 2,800–3,200 kWh. Still a substantial amount of electricity.
And here's the thing that most articles miss: the gap can narrow further when you put panels on both slopes of an east-west roof. Installing across both faces lets you compensate for the per-panel reduction by fitting more panels in total, and it creates a broader, more even generation curve across the day — producing useful power from early morning right through to early evening, rather than concentrating output in the middle hours.
The self-consumption advantage — why east-west can beat south for working households
Here is where east-west roofs have a genuine edge over south-facing ones, and it's a point that matters enormously to your actual savings.
A south-facing system produces a sharply peaked generation curve, with output concentrated around solar noon — roughly 11am to 2pm. For most working households, nobody is home at that time. That midday electricity has to be exported to the grid, where you earn a Smart Export Guarantee (SEG) rate of roughly 4p–15p per kWh (depending on your tariff), instead of being used in the house where it saves you the full import rate.
At the current Ofgem price cap, electricity costs around 26p per kWh. Every unit you consume directly from your panels saves you that full 26p. Every unit you export earns you far less. So the timing of generation has a huge effect on the financial return — sometimes as much as the total volume.
East-facing panels generate most of their output in the morning, which powers the first peak of the day — kettles, showers, toasters, washing machines started before work. West-facing panels do better in the afternoon and early evening, which is when most families are home, cooking and watching TV. That alignment with actual household demand is why east-west splits can deliver higher self-consumption rates than south-facing arrays for households that follow a typical working pattern.
In summer, when the UK gets long daylight hours, east-west panels capture useful energy across a wider window — earlier in the morning and later into the evening — than a south-facing system peaking at midday. See our guide to solar panel payback time in the UK for a full look at how self-consumption rates affect your returns.
A worked example: a typical 3-bed semi with an east-west roof
This is an illustration only — actual savings depend on your household, roof, location, and usage. But it gives a sense of how the numbers can work.
- System: 4kWp split across east and west slopes (around 8–10 panels per side)
- Estimated annual generation: around 2,900–3,300 kWh (roughly 15–20% below a south-facing equivalent)
- Self-consumption rate: a working household with morning and evening usage might self-consume 45–52% of generation
- Saving per self-consumed unit: around 26p (Ofgem price cap rate, July–September 2026)
- Additional SEG income: on exported surplus, at current flat rates of 4p–15p per kWh
- Illustrative annual saving: a typical 3-bedroom household in this scenario might save around £350–£600 a year on bills, with additional SEG income on top
That's not a guarantee — it's an illustration of the range. Your actual saving depends on how much electricity you use, when you use it, your tariff, your roof's exact orientation, and your location in the UK. An MCS-certified installer will calculate a proper site-specific yield estimate before any work begins.
What about inverters — does the technology cope with east-west?
Yes, easily. A standard string inverter with dual MPPT (Maximum Power Point Tracking) inputs handles east-west configurations by treating each roof slope as a separate string, so the morning output on the east side doesn't interfere with the afternoon output on the west. Alternatively, microinverters or power optimisers work well because they optimise each panel independently — useful if one slope receives any shading. Your installer will recommend the right setup for your roof.
Does an east-west roof qualify for 0% VAT and the Smart Export Guarantee?
Yes on both counts. The 0% VAT rate on residential solar panel installations applies regardless of which direction your roof faces — there is no orientation requirement. As long as you use an MCS-certified installer and the system meets the technical requirements, you benefit from the VAT relief.
The Smart Export Guarantee (SEG) is equally available to east-west installations. You need an MCS-certified install and an export-capable smart meter. Flat SEG rates in 2026 run from around 4p to 15p per kWh depending on supplier, with time-of-use tariffs offering more in some cases. For the latest rates, see our Best Smart Export Guarantee Rates UK 2026 guide.
When solar on an east-west roof isn't worth it
Being straight about this is important, because not every roof should have solar on it.
Heavy shading is the biggest concern. The Energy Saving Trust points out that shading can have an even bigger impact on output than roof orientation — a south-facing roof that's heavily shaded during the day may generate less than an unshaded east or west-facing roof. If your east or west slopes are significantly shaded by trees, neighbouring buildings, or a chimney stack for large parts of the day, the numbers may not stack up. Our guide to solar panels and shade covers this in detail.
Very steep pitches widen the output gap between east-west and south-facing systems, so a near-vertical wall-mounted installation would need careful assessment.
High midday electricity use (if someone is working from home all day, for example) shifts the advantage back toward south-facing, because you'd be home to use the midday peak from south-facing panels directly.
A very small usable roof area on both slopes may limit the system size to the point where the economics are marginal — though this is a size question more than an orientation one.
If any of these apply, it's worth getting a proper assessment rather than guessing. An MCS-certified installer will give you a site-specific yield estimate and a clear picture of what the numbers actually look like for your property.
Getting quotes for an east-west roof: what to check
When you get quotes, ask each installer to show you the yield estimate methodology — reputable installers use MCS-aligned processes that account for orientation, tilt, and shading explicitly. Don't accept a quote that just gives you a headline panel count without showing the expected annual generation in kWh. And make sure any savings estimates are presented as ranges, not fixed figures — because they depend on how and when you use electricity.
Always get at least three quotes from MCS-certified installers so you can compare both price and the quality of the yield modelling. FairSolar connects you with vetted, MCS-certified local installers — free, with no obligation, and no pushy sales calls. If you'd like to understand more about what to look for, our Solar Quote Red Flags guide covers the things that should make you walk away.
Frequently asked questions
Do solar panels work on an east-facing roof?
Yes. The Energy Saving Trust confirms that east-facing roofs still work well for solar. East-facing panels generate most of their output in the morning, which aligns with the first peak of household electricity use. You'll typically generate around 15–20% less annually than a south-facing system, but for many households the financial returns are still strong.
Are solar panels worth it on a west-facing roof?
For most households, yes. West-facing panels produce most of their electricity in the afternoon and early evening, which is often when families are home using the most power. That alignment with actual demand can mean more of your solar electricity is used directly in the home — saving you the full unit rate rather than earning the lower export rate. The output is around 15–20% below a south-facing system, but the self-consumption advantage can offset much of that difference.
How much less do east-west solar panels generate compared to south-facing?
According to the Energy Saving Trust, east or west-facing systems generally produce around 15–20% less electricity annually than a system facing directly south. If you install panels across both the east and west slopes of a roof, you can fit more panels and create a broader generation profile across the day, which narrows the overall output gap.
Can I get the 0% VAT and Smart Export Guarantee on an east-west solar system?
Yes to both. The 0% VAT rate on residential solar installations has no orientation requirement — it applies regardless of which way your roof faces, provided you use an MCS-certified installer. The Smart Export Guarantee is equally available, paying you for surplus electricity exported to the grid. You'll need an MCS-certified install and an export-capable smart meter to claim it.
Should I add a battery if my roof faces east-west?
A battery can make an east-west system even more effective by storing any midday surplus from the west-facing panels for use in the evening. However, batteries add significant upfront cost, and whether they make financial sense depends on your usage patterns and the system size. It's worth getting quotes with and without battery storage so you can compare the payback periods directly.