Specialist solar panels for schools in Windsor
The planning record around Windsor carries 2 school and college solar applications, the largest of them 490 kWp. What we come back with is the usable roof area, the modelled output against your meter data, and the routes schools use to pay for it.
441,500 kWh a year, modelled for a 490 kWp array on roughly 1,455 sqm of clear roof. That is the median size schools around Windsor have applied for. Source: EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss.
Book a roof survey in Windsor- 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.
Schools near Windsor already on the planning record
The Renewable Energy Planning Database records 2 school and college solar schemes in the SL4 postcode district. A 260 kWp roof mounted array at St Johns Beaumont School, Priest Hill was refused. The applicant on record is St Johns Beaumont School. The Windsor Boys School, Maidenhead Road applied for 490 kWp of roof mounted array, and that application holds consent and is awaiting construction. The applicant on record is Solar Options for Schools Limited.
We had nothing to do with any of them. They are public planning records, and they are on this page because the useful question for a governing body is not whether school solar works in the abstract but whether it has been consented nearby. Source: Renewable Energy Planning Database, Q1 2026.
The site plan at the top of this page is a generic estate drawn to show scale and sequencing. It is not St Johns Beaumont School, Priest Hill, and it is not any other building in Windsor. We hold no drawings, roof data or consumption data for the schools named above.
The median array applied for here is 375 kWp, with the largest at 490 kWp. At 375 kWp you are covering roughly 1,114 square metres of roof once walkways, edge zones and rooflight setbacks come out, which on most sites means a sports hall plus one teaching block rather than the whole estate.
| Site on record | Applicant on record | Size | Mounting | Status |
|---|---|---|---|---|
| St Johns Beaumont School, Priest Hill | St Johns Beaumont School | 260 kWp | Roof | Application Refused |
| The Windsor Boys School, Maidenhead Road | Solar Options for Schools Limited | 490 kWp | Roof | Awaiting Construction |
School rooftop solar across Berkshire
A one kilowatt-peak array on a shallow pitched roof in Windsor models at 901 kWh a year, from modelled irradiation of 1,157 kWh per square metre in the plane of the array (EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss). That is roughly 2 percent above the mean across the towns we cover, so latitude is working slightly in your favour here.
Scaled up, a 490 kWp array, sized to the median array applied for at schools around Windsor itself, models at about 441,500 kWh a year before shading, and needs roughly 1,455 square metres of clear roof. That size is not one we chose. It is what schools in this district have actually applied for.
Spread across the year that is about 113,000 kWh landing in July and August and roughly 23,000 kWh across December and January. Scottish and Southern Electricity 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.
Windsor ranks 6 of 8 towns we cover in Berkshire on modelled yield, against a national mean of 886 kWh per kWp. The county runs from 891 to 910, a spread of 19 kWh per kWp. Within Berkshire that difference is small enough to ignore: where the building sits is not what decides this scheme, your consumption pattern is.
The summer holiday problem for a Windsor school
25.6 percent of the annual output modelled for Windsor 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. July is the single strongest month here at 13.9 percent of the annual total, and it falls almost entirely inside the holiday.
The inverse holds at the other end. December and January together return only 5.2 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 5.7 times as much in July 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.
Summed over the year, about 49 percent of what a school roof makes arrives while the school is open. For a business trading every weekday the equivalent is roughly 71 percent. Nothing about Windsor changes that ratio much, but plenty about your own site changes what to do with it.
The same mismatch repeats every day. Peak generation lands between eleven and three, the timetable ends shortly after, and by four the site is down to caretaking and cleaning. An annual consumption figure cannot show that, which is why we ask for the half hourly data instead.
A Windsor governing body should read that as a sizing constraint, not a reason to stop. The base load that runs through the holidays, servers, comms, refrigeration, ventilation and hot water, is the floor the array should be built up from, and everything above it has to be justified by storage, export or summer occupancy.
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 | 25 | 16 | 9 |
| Feb | 15 | 38 | 20 | 18 |
| Mar | 21 | 72 | 49 | 23 |
| Apr | 12 | 103 | 41 | 62 |
| May | 17 | 120 | 66 | 54 |
| Jun | 21 | 124 | 87 | 37 |
| Jul | 11 | 125 | 44 | 81 |
| Aug | 0 | 106 | 0 | 106 |
| Sep | 20 | 83 | 55 | 28 |
| Oct | 17 | 52 | 29 | 23 |
| Nov | 21 | 31 | 22 | 9 |
| Dec | 15 | 22 | 11 | 11 |
| Year | 190 | 901 | 440 | 461 |
How many schools Windsor and Maidenhead has
Windsor and Maidenhead has 65 open state-funded schools and colleges on the DfE register teaching 22,633 pupils between them. Source: DfE Get Information About Schools.
The split is 49 primary, 14 secondary and 2 special, at an average of 348 pupils a site. At 3.5 primaries to every secondary, most of the buildings here are small. That is not a reason to skip them, but it does mean the usable area on a primary is a hall roof and a teaching block rather than an estate.
For a trust with more than one site in Windsor and Maidenhead, the first survey is worth running across the whole estate. It tells you which roofs are near the end of their covering life, which have the switchboard headroom, and therefore which one should carry the first array.
Grid connection through Scottish and Southern Electricity Networks
Scottish and Southern Electricity 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.
Across Berkshire the planning database records 83 solar schemes totalling 317 MW, of which 8 are operational (REPD Q1 2026).
Start with the Windsor roof
Lenzie Consulting Ltd arranges roof surveys for schools across Berkshire. Send the school postcode and a rough idea of the roof area, and the last twelve months of half hourly meter data if the school holds it. We come back with what the roofs can carry, what they would generate against your own consumption, and the funding routes open to a school.
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 Windsor schools
- How much would a school roof near Windsor generate?
- Modelled at 901 kWh per kWp a year, a 490 kWp array on a Windsor school models at about 441,500 kWh. What decides whether that is worth doing is how much of it the school uses itself, not the total. Source: EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss.
- How does the school year affect a solar scheme in Windsor?
- It goes somewhere, just not into the timetable. 25.6 percent of the Windsor generating year lands in July and August (EU PVGIS v5.2), and a closed school still runs servers, comms, refrigeration and ventilation. What that base load does not absorb is either stored, exported under an agreement with Scottish and Southern Electricity Networks, or a sign the array is too big. We test which before sizing anything.
- Which network operator handles the connection at a Windsor school?
- Applications go to Scottish and Southern Electricity Networks, who run the network across Berkshire. An export-limited offer usually still works for a school, because the summer surplus is the part you were least likely to be paid much for anyway.
- What does Windsor and Maidenhead require for solar on a school building?
- Roof-mounted solar on a non-domestic building often falls within permitted development under Part 14 of the General Permitted Development Order, subject to limits on how far the panels stand proud of the roof plane and, above a threshold, to prior approval from Windsor and Maidenhead on siting and design. Listed buildings and conservation areas are the usual exceptions. We put the position to Windsor and Maidenhead before a design is finalised.
- Has a school near SL4 already done this?
- 2 school schemes are on record in this postcode district, including a 260 kWp array at St Johns Beaumont School, Priest Hill that was refused. We were not involved in it. It is a public planning record, and it matters less as proof that solar works than as evidence of what this authority and this network operator have already accepted. Source: Renewable Energy Planning Database, Q1 2026.
- How many schools are there around Windsor?
- Windsor and Maidenhead has 65 open state-funded schools and colleges on the DfE register, with 22,633 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.