Specialist solar panels for schools in Devizes
A school roof in Devizes makes 6 times as much in July as it does in December, and the school year runs against that curve rather than with it. 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.
289,900 kWh a year, modelled for a 320 kWp array on roughly 950 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 Devizes- 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 Wiltshire
A one kilowatt-peak array on a shallow pitched roof in Devizes models at 906 kWh a year, from modelled irradiation of 1,161 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 320 kWp array, sized to what the nearest school scheme on record applied for, 10 miles away at Chippenham, models at about 289,900 kWh a year before shading, and needs roughly 950 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 73,600 kWh landing in July and August and roughly 14,800 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.
Devizes ranks 5 of 8 towns we cover in Wiltshire on modelled yield, against a national mean of 886 kWh per kWp. The county runs from 894 to 923, a spread of 29 kWh per kWp. Within Wiltshire that difference is small enough to ignore: where the building sits is not what decides this scheme, your consumption pattern is.
What the planning record shows around Devizes
The SN10 postcode district has no education solar entry in the Renewable Energy Planning Database. Almost no school array is large enough to be captured there reliably, so the absence tells you about the reporting threshold and very little about what is already on the roofs around Devizes.
The nearest education scheme on the record is 10 miles from Devizes, at Chippenham: 320 kWp at Wiltshire College, Lackham, applicant Wessex Energy Solutions, which holds consent and is awaiting construction. That is someone else's application, not ours, and it is here because it shows what Wiltshire planning has already accepted at an education site. Source: Renewable Energy Planning Database, Q1 2026.
The summer holiday problem for a Devizes school
25.4 percent of the annual output modelled for Devizes 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 13.8 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 5.1 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 6 times as much in July as it does in December, and August alone outproduces December by about 5 to one. 74 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.
Nationally this comes out at about 49 percent of annual generation falling on a session day. A business open every weekday sees roughly 71 percent. The 22 point gap is what a school appraisal has to absorb, and it is much the same in Devizes as anywhere else.
The weekly pattern repeats the annual one. Saturdays and Sundays generate as well as any other day and consume almost nothing, so before storage or export is even discussed it is worth knowing what the site does at a weekend, which only half hourly data will tell you.
The conclusion is not that a Devizes school should do nothing. It is that the array should be sized to the load that survives the holidays, which is usually the server room, the catering refrigeration, the ventilation and the hot water, plus whatever the site lets out over the summer. Anything above that line needs storage or an export agreement with Scottish and Southern Electricity Networks to earn its keep.
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 | 39 | 21 | 18 |
| Mar | 21 | 74 | 50 | 24 |
| Apr | 12 | 106 | 42 | 64 |
| May | 17 | 123 | 67 | 56 |
| Jun | 21 | 124 | 87 | 37 |
| Jul | 11 | 125 | 44 | 81 |
| Aug | 0 | 105 | 0 | 105 |
| Sep | 20 | 83 | 55 | 28 |
| Oct | 17 | 51 | 28 | 23 |
| Nov | 21 | 30 | 21 | 9 |
| Dec | 15 | 21 | 10 | 11 |
| Year | 190 | 906 | 441 | 465 |
How many schools Wiltshire has
Wiltshire has 237 open state-funded schools and colleges on the DfE register teaching 68,445 pupils between them. Source: DfE Get Information About Schools.
The split is 201 primary, 28 secondary, 6 special and 2 further education, at an average of 289 pupils a site. At 7.2 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 Wiltshire, 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
Connections around Devizes are handled by Scottish and Southern Electricity Networks, which sets the export limit for the site. Above 3.68 kW per phase the connection runs under G99, so the export limit is agreed in advance rather than assumed. Where the local network is constrained, an export-limited connection usually still makes the scheme work, because a school uses most of what the roof makes during the working day.
Across Wiltshire the planning database records 159 solar schemes totalling 1585 MW, of which 56 are operational (REPD Q1 2026).
Start with the Devizes roof
The first survey answers three questions at once: what the roofs carry, what they generate against your own timetable, and how a Devizes 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 Devizes schools
- Is there enough sun around Devizes for this to be worth doing?
- The model gives 906 kWh a year for every kWp installed at this latitude, so a 320 kWp array comes out at roughly 289,900 kWh a year before shading. It needs about 950 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 Devizes school waste its generation in August?
- 25.4 percent of the modelled annual output for Devizes 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 Scottish and Southern Electricity Networks. We model all three against your half hourly data before an array is sized.
- Will the network around Devizes accept the export?
- Scottish and Southern Electricity Networks is the distribution network operator for Wiltshire. 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.
- Is planning permission needed for panels on a school in Devizes?
- Usually permitted development covers a roof array on a school, with prior approval from Wiltshire needed above a capacity threshold. A ground mounted array in the grounds is a different question and much more likely to need a full application. We check both before design sign-off.
- How many schools are there around Devizes?
- Wiltshire has 237 open state-funded schools and colleges on the DfE register, with 68,445 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.