Specialist solar panels for schools in Westminster
UK Power Networks runs the network around Westminster, and on a school site their answer on export shapes the design as much as the roof pitch does. We look at the roof, the switchboard and the timetable in that order, then set the array size against what the site draws in term time.
153,300 kWh a year, modelled for a 170 kWp array on roughly 505 sqm of clear roof. That is the size applied for at the nearest school scheme on record. Source: EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss.
Book a roof survey in Westminster- 1 teaching block
- 2 hall and kitchen
- 3 sports hall
- 4 1960s block, no array
- first phase
- later phase
Illustrative layout for an estate of this size. The array is drawn at about 345 kWp, roughly 53 percent of the 650 kWp these three roofs would hold, because a school sizes to the load it can use in term time rather than to the roof it has: generation it cannot use is exported at a much lower rate than it pays to import. The hatched block carries no array because its structure has not been assessed, which on a school of that era is the usual starting point rather than an exception. Your own figures, and which of your blocks can take an array, come from the roof survey.
School rooftop solar across Greater London
A one kilowatt-peak array on a shallow pitched roof in Westminster models at 902 kWh a year, from modelled irradiation of 1,160 kWh per square metre in the plane of the array (EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss). Westminster models 2 percent above our mean. That is a real advantage, though a smaller one than the difference between an array matched to the timetable and one matched to the roof.
Scaled up, a 170 kWp array, sized to what the nearest school scheme on record applied for, 19 miles away at St Albans, models at about 153,300 kWh a year before shading, and needs roughly 505 square metres of clear roof. We take the size from the nearest real application rather than a round number, so the example is anchored to something a planning officer has already seen.
Spread across the year that is about 38,900 kWh landing in July and August and roughly 8,100 kWh across December and January. UK Power Networks sets what may go back onto the network here, so the July figure is the one worth putting in front of a governing body first.
Westminster ranks 41 of 50 towns we cover in Greater London on modelled yield, against a national mean of 886 kWh per kWp. The county runs from 847 to 987, a spread of 140 kWh per kWp. On a 500 kWp array that is about 70,000 kWh a year between the strongest and weakest town in the county.
What the planning record shows around Westminster
There is no school entry for Westminster and the area around it in the Renewable Energy Planning Database. The register is dependable for anything from a megawatt upward and incomplete below it, and a school array is usually nearer a fifth of a megawatt, so this says more about the threshold than about Westminster.
The nearest education scheme on the record is 19 miles from Westminster, at St Albans: 200 kWp at Samuel Ryder Academy, applicant Scholars Education Trust, which was withdrawn before determination. That is someone else's application, not ours, and it is here because it shows what Hertfordshire planning has already accepted at an education site. Source: Renewable Energy Planning Database, Q1 2026.
The summer holiday problem for a Westminster school
25.4 percent of the annual output modelled for Westminster arrives in the two months a school uses least (EU PVGIS v5.2). Term ends in the third week of July and the buildings stay largely empty until September. June is the strongest single month here at 13.7 percent of the annual total, which is still term time, and that works slightly in your favour against towns whose curve peaks in July.
The inverse holds at the other end. December and January together return only 5.3 percent of the year, and those are the months with the heating, the lighting and the full timetable all running at once. The roof makes 5.6 times as much in June as it does in December, and August alone outproduces December by about 4.8 to one. 73 percent of the year arrives between April and September, and the point of that figure is not that the summer half goes unused, because April, May and June are full teaching months that draw hard. It is that the concentration peaks in the few weeks at the end of it when the building is shut.
Across the country the arithmetic settles at roughly 49 percent of output on a session day, against about 71 percent for a weekday business. That figure hardly varies by location, which is why the local numbers that matter here are the yield, the roofs and what has already cleared planning nearby.
Then there is the afternoon. From roughly three o'clock the building empties while the roof is still working, so a system sized on annual consumption will over-generate in exactly the hours nobody is there. We size on half hourly data for that reason.
That argues for a particular shape of scheme rather than against one. Size to the load that does not stop at the end of term, count in lettings, holiday clubs and summer works honestly rather than optimistically, and then decide whether storage or an export arrangement with UK Power Networks pays for the surplus that is left.
We set out the whole argument about term dates and the generation curve on the home page, and what it does to a payback figure under costs.
- generated while the school is open
- generated at a weekend or in the holidays
The same figures as a table
| Month | Session days | Output, kWh per kWp | School open | School closed |
|---|---|---|---|---|
| Jan | 20 | 26 | 17 | 9 |
| Feb | 15 | 38 | 20 | 18 |
| Mar | 21 | 73 | 49 | 24 |
| Apr | 12 | 105 | 42 | 63 |
| May | 17 | 119 | 65 | 54 |
| Jun | 21 | 124 | 87 | 37 |
| Jul | 11 | 124 | 44 | 80 |
| Aug | 0 | 105 | 0 | 105 |
| Sep | 20 | 83 | 55 | 28 |
| Oct | 17 | 52 | 29 | 23 |
| Nov | 21 | 31 | 22 | 9 |
| Dec | 15 | 22 | 11 | 11 |
| Year | 190 | 902 | 441 | 461 |
Grid connection through UK Power Networks
UK Power Networks is the network operator here, and their answer on export capacity shapes the design. Any commercial array above 3.68 kW per phase connects under G99 rather than G98, and the application fixes what you are allowed to push back onto the network. If the local network is tight, limiting export rarely breaks the case here: most of the generation is consumed on site while the building is working.
How many schools Westminster has
Westminster has 54 open state-funded schools and colleges on the DfE register teaching 19,058 pupils between them. Source: DfE Get Information About Schools.
The split is 37 primary, 11 secondary, 3 special and 3 further education, at an average of 353 pupils a site. A ratio of 3.4 to one tells you where the roof area is. It is not with the 37 primaries, which mostly offer a hall and a teaching block each, but with the larger sites that were built with a sports hall and a dining block attached.
Where a multi-academy trust holds several of those sites, surveying the estate in one pass beats taking a roof at a time. The design work, the connection applications and the procurement paperwork are the same job repeated, and a trust that runs them together gets a better answer on all three.
Start with the Westminster roof
The first survey answers three questions at once: what the roofs carry, what they generate against your own timetable, and how a Westminster school pays for it. Send the postcode, an approximate roof area per block and half hourly meter data if the school can get it from its supplier.
Lenzie Consulting Ltd arranges the survey and passes your details to an MCS-certified installation partner so they can quote. We do not carry out the installation ourselves.
Questions governors ask us about Westminster schools
- Is there enough sun around Westminster for this to be worth doing?
- The model gives 902 kWh a year for every kWp installed at this latitude, so a 170 kWp array comes out at roughly 153,300 kWh a year before shading. It needs about 505 square metres of clear roof once walkways and rooflight setbacks are allowed for. Source: EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss.
- Does a Westminster school waste its generation in August?
- 25.4 percent of the modelled annual output for Westminster falls in July and August, when the buildings are closed for most of six weeks (EU PVGIS v5.2). It does not go to waste, but it only has three places to go: the base load that runs regardless, such as servers, catering refrigeration and ventilation; storage; or export under an agreement with UK Power Networks. We model all three against your half hourly data before an array is sized.
- Will the network around Westminster accept the export?
- UK Power Networks is the distribution network operator for Greater London. Anything above 3.68 kW per phase connects under G99, and the application fixes the export limit. On a school site the incoming supply is often the binding constraint rather than the roof, so we ask that question before anyone sizes an array.
- How many schools are there around Westminster?
- Westminster has 54 open state-funded schools and colleges on the DfE register, with 19,058 pupils on roll. Source: DfE Get Information About Schools. We survey across the whole of that area, and where a trust holds several sites we look at them in one pass.