Is Leeds sunny enough for solar panels?

Otley to Wetherby: how much the district varies

The fairest way to settle the question is to model it. We ran twelve points across the Leeds district through PVGIS, the European Commission's solar model, which draws on satellite estimates of sunlight for 2005-2023. Every point got the same set-up: one kilowatt of panels facing due south at a 35° tilt, with the model's standard 14% allowance for losses in cables and equipment (PVGIS). The results fall in a tight band. Otley, in Wharfedale on the north-west edge of the district, comes out lowest, at 934 kWh a year from every kW installed. Wetherby, further down the same river on the eastern edge, comes out highest at 972 kWh. That gap of 38 kWh works out at 4.1% on our arithmetic.

Most of the city lands within a few kWh of the middle. The city centre models at 952 kWh, Roundhay at 951 and Morley at 950, while Armley, Beeston and Holbeck all give 949. The four lowest results, Otley, Horsforth, Burley and Headingley, all lie north-west of the centre. Most of Otley's shortfall comes in the dark months: a south-facing kW there models at 25 kWh in December, against 32 kWh in the city centre.

Now compare that with what happens on a single roof. Turning the same panels in the city centre from south to east costs 199 kWh per kW a year, roughly 5 times the whole Otley–Wetherby gap. For a household weighing up solar, the slope you have counts for far more than the postcode you live in, and the roof picker lets you look up the slope you actually have.

What the stations either side of Leeds record

The Met Office long-term averages we used come from two stations outside the district, one on each side of it. To the east, Church Fenton averaged 1,525 hours of sunshine a year over 1991–2020, with 620 mm of rain falling on 116 days (Met Office, Church Fenton). To the west, up the Aire valley, Bingley averaged 1,057 mm of rain on 156 days over the same thirty years; that station has no sunshine record in the series (Met Office, Bingley). On our arithmetic the western station collects about 70% more rain, spread across 40 more rain days a year.

The rain gradient lines up with the PVGIS ranking, even though the two come from different methods: PVGIS works from satellite readings, not from these ground stations. The cloud that brings rain also dims the light, which fits the north-western points edging lower and Wetherby edging higher. What neither set of figures shows is a cliff edge. Otley, out on the western side, still models within 4.1% of Wetherby, because grey weather cuts output back rather than switching it off. They are long-run averages as well, so any single year can land a little above or below them depending on how the summer turns out.

Cloud, drizzle and daylight

Sunshine hours measure only the time when direct sun is strong enough to show up on the station's recorder. Solar panels respond to every bit of light that reaches them, including the diffuse daylight scattered through cloud. On a heavy, overcast day output falls a long way, but it does not fall to nothing, and a run of bright-grey days in April or September adds up. That is how a corner of England with about 1,525 recorded sunshine hours a year at the station to its east can still model at 934 kWh or more per kW right across the district.

Cool weather is not a handicap in itself. Panels turn light into electricity slightly more efficiently when they run cool, so a clear, cold spring morning suits them well. Rain does the panels no harm either, and on a pitched roof it rinses away light dust and pollen. Bird mess, moss and leaf litter are another matter; the guide to looking after panels covers what rain leaves behind and how to check that a system is producing what it should.

Month by month in central Leeds

PVGIS also breaks the year into months. Its best fixed tilt for the city centre is 41°, facing almost due south, and at that angle one kW of panels makes about 956 kWh a year (PVGIS). The peak comes in May, at 116 kWh, and July runs close at 114. December is the weakest at 35, and January only a little better at 37, so the best month brings in about 3.3 times as much as the worst.

Split the year in two and the pattern is plain. April through September brings in 642 kWh per kW, about 67% of the total, leaving 315 kWh for October through March. Scaled up to 4.5 kWp, which the Energy Saving Trust uses as its typical home system, that comes to around 158 kWh in December against 522 kWh in May, and about 4,302 kWh across the year (Energy Saving Trust; our arithmetic). Ofgem's typical figure for a household's electricity use is 2,500 kWh a year (Ofgem), so over twelve months a system of that size makes more than such a home uses, while in midwinter it covers only part of the need.

That mismatch is the practical point for any Leeds household. Surplus in summer goes out to the grid unless something in the house uses it or a battery stores it, and demand in winter is still met mostly from the grid. The battery guide deals with keeping the surplus for the evening, and the guide to export payments with selling it.

Flat roofs and slopes that miss the south

Plenty of Leeds roofs do not face due south at a steep pitch. Panels lying flat in the city centre model at 782 kWh per kW a year, about 18% below a south slope at 35° (PVGIS). Flat-roof systems are often set on frames that tilt them, which wins back much of that gap, though the frames and their ballast need a roof strong enough to carry them. Panels that really do lie flat also hold dirt and standing water for longer than tilted ones.

East and west slopes in the city centre give 753 and 740 kWh per kW. That is less from each panel, but the output is spread into the morning or the evening, which can suit a household that is out in the middle of the day. A north slope drops to 506, low enough that most households would look at another roof first. In streets of back-to-backs, each house has a single slope pointing whichever way the terrace was laid out, so the question of direction was settled when the street was built; the back-to-back guide works through what that means for a house with one roof face.

So, is Leeds sunny enough?

On the modelled figures, yes, for most roofs facing anywhere from east round through south to west, and the answer barely shifts between Otley and Wetherby. The weather sets the ceiling, but within Leeds the difference between districts is smaller than the difference between two slopes of the same house.

One caution about every figure on this page: PVGIS models an open roof with nothing close by to block the light. A chimney stack on the south side, a neighbouring gable that rises higher, or a mature tree in the next garden can pull a real roof well below the table, especially in winter when the sun stays low over the rooftops. That is local shade, not Leeds weather, and it is the first thing an installer's survey of the roof should measure.

What decides the case for a particular home is everything the weather does not: the direction and pitch of the roof, shade from chimneys, dormers and trees, how much electricity the household uses in daylight, and the price of the system. The cost of solar in Leeds page covers prices using the government's Yorkshire and the Humber figures, and the glossary untangles kW, kWp and kWh if the units start to blur. For a view on one particular roof, the question form on this page reaches the publisher of this guide.