Does My House Get Enough Sun for Solar Panels? UK Guide

The short answer: most UK homes get enough sun. As long as your main roof faces somewhere between southeast and southwest and is not heavily shaded, solar panels will generate meaningful electricity throughout the year — even in Scotland. The questions worth asking are not whether there is any sun, but how much roof area is usable and whether shading rules out the best-facing sections. This guide gives you a practical way to check both before spending a penny on quotes.

How much sun do UK solar panels actually need?

The UK receives between 750 and 1,050 kilowatt-hours of solar irradiance per square metre per year depending on where you live — enough to make solar a viable investment across essentially the whole country. A south-facing, correctly tilted system generates roughly 850–1,000 kWh of electricity per kilowatt-peak (kWp) of installed capacity per year, according to the European Commission's PVGIS satellite irradiance dataset, which forms the basis of MCS installer calculations across the UK.

Regional variation is real but rarely decisive:

• Cornwall and Devon: 1,000–1,050 kWh/kWp per year
• South-East England: 950–1,000 kWh/kWp
• London and the South Midlands: 900–950 kWh/kWp
• North-West England and Yorkshire: 850–900 kWh/kWp
• Central Scotland: 800–850 kWh/kWp
• Highlands and Islands: 750–800 kWh/kWp

A 4 kWp system in Yorkshire therefore generates roughly 3,400–3,600 kWh a year — close to the average UK household's annual electricity consumption of around 3,300–3,500 kWh, as reported by Ofgem. A 4 kWp system on the south coast would produce 4,000–4,200 kWh. The difference is significant in payback calculations, but neither figure makes solar unviable. For a location-specific estimate, see our guide to solar panel output by region.

Does your roof face the right way?

South-facing at roughly 30–35° pitch is treated as the benchmark — but the range of workable orientations is far wider than most people expect. The Energy Saving Trust and PVGIS data used by MCS installers consistently show that roofs within 45° of due south lose only a small fraction of annual output:

• South-facing (~35° pitch): 100% yield — the ideal
• Southeast or southwest: 85–95% of south-facing — barely any penalty
• Due east or due west: 80–85% of south-facing — a meaningful reduction, but still financially viable in most cases
• North-facing: typically 50–60% of south-facing or less — rarely worth installing on as the only surface

Pitch angle matters less than compass direction. Standard UK roofs pitch at 30–40°, which is almost exactly the optimal tilt for the UK's latitude. A roof that is a few degrees steeper or shallower than ideal loses less than 2% of annual output. Our detailed roof orientation guide breaks down what the kWh difference means in real savings at each compass point.

If you have both a south-facing and an east-facing section of roof, an installer will typically prioritise the south-facing area first and add east-facing panels only if budget and roof space allow.

Is your roof shaded?

Shading is the most important suitability factor, and the one most likely to make or break a system's economics. Unlike orientation, where even an east-facing roof loses only 15–20% of output, serious shading can reduce generation far more than the shaded area alone would suggest — particularly with standard string inverter systems, where one shaded panel drags down the whole string.

The most common shading sources on UK roofs are:

• Chimneys and party wall stacks — cast long shadows in the low winter sun and early mornings
• Mature trees — especially those to the south, southeast or southwest that catch the midday sun
• Neighbouring buildings — terrace and semi-detached homes are particularly exposed if a taller building sits to the south
• Dormer windows and roof features — even small protrusions create shadows that track across panels through the day
• Aerial and satellite dishes — small but worth noting if they cannot be relocated

As a rough guide, based on MCS installer assessments:

• Shading affects fewer than 10–15% of your usable south-facing area → solar is almost certainly still viable, especially with microinverters or power optimisers
• Shading affects 20–30% of the generating area, or falls in the middle of the day → the economics tighten; get a careful site-specific calculation before committing
• Shading affects more than 30% of usable roof area for a meaningful part of the solar day → the roof is a poor candidate; no technology fully compensates for serious all-day shading

For a full explanation of how shading affects system output — including why string inverters are disproportionately vulnerable and when microinverters help — see our guide to solar panel shading.

Check your roof with our shadow map tool

Rather than estimating from memory, you can check your actual roof's shadow pattern throughout the year using our free solar shadow map. Search your address, pick a date and time, and the tool overlays a computed shadow mask on a 3D map of your neighbourhood.

The shadows are calculated from the Environment Agency's LIDAR Composite Digital Surface Model — one-metre resolution height data captured for England from aerial surveys — which captures actual building heights, roof pitches, tree canopies and other obstructions. This is the same underlying data professional installers use when conducting shade surveys. Unlike simplified satellite tools, it shows where shadows fall on your specific roof at specific times of day and year.

A few things worth checking with the tool:

• How much of your south-facing roof is shadow-free at midday in December — the worst-case scenario
• Whether a neighbouring tree or building casts a shadow across the middle of your roof in the morning or late afternoon
• How the shadow pattern compares in summer vs winter — a tree that blocks winter sun may be less of an issue in summer when the sun is higher

Note: the LIDAR data currently covers England. If you are in Scotland, Wales or Northern Ireland, the tool will still show the map but the shadow overlay will not be available.

Other tools to check your solar potential

The European Commission's PVGIS tool is the industry standard for location-specific output estimates, and it is free to use. Enter your address, set your panel orientation and tilt, and it returns an annual generation estimate with monthly breakdowns, based on satellite irradiance records going back decades. The Energy Saving Trust also provides a simpler solar calculator aimed at homeowners. Our step-by-step guide to using PVGIS for a UK home walks through the inputs and what the numbers mean.

These tools estimate how much sun reaches your location. They do not, however, account for shading from specific buildings or trees on your own street. That is where the shadow map tool above adds something those calculators cannot.

When solar probably is not right for your roof

Most UK homes pass a basic suitability check, but a few situations make solar a poor fit:

• North-facing roof only, with no south-facing or side section — output is too low to justify the capital cost in most cases
• Significant shading from a building or large tree to the south — particularly if the shadow covers the roof during the midday window (roughly 10am–2pm)
• Roof needing replacement within five years — panels should ideally be removed and reinstalled when re-roofing, which adds cost; better to reroof first
• Listed building or conservation area restrictions — solar on listed buildings requires Listed Building Consent; conservation area rules vary by council
• Very small usable roof area — fewer than six panels' worth of unshaded space makes the economics thin, though high-efficiency panels can help on constrained roofs

The bottom line

If your main roof faces south, southeast, southwest, east or west — and is not heavily shaded — your house almost certainly gets enough sun for solar to be worth investigating. Use the shadow map to check shading, and PVGIS to estimate annual output for your location. If both look reasonable, the next step is understanding how many panels you need and what the system will cost. The honest bottom line on whether solar makes financial sense is in our are solar panels worth it guide.