Specialist solar panels for schools in Lydney
National Grid Electricity Distribution runs the network around Lydney, 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.
905 kWh per kWp a year at this latitude, so a 150 kWp array, the size applied for at the nearest school scheme on record, models at about 135,800 kWh. Source: EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss.
Book a roof survey in Lydney- 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 Gloucestershire
A one kilowatt-peak array on a shallow pitched roof in Lydney models at 905 kWh a year, from modelled irradiation of 1,162 kWh per square metre in the plane of the array (EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss). Lydney 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 150 kWp array, sized to what the nearest school scheme on record applied for, 22 miles away at Keynsham, models at about 135,800 kWh a year before shading, and needs roughly 446 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 34,900 kWh landing in July and August and roughly 6,700 kWh across December and January. National Grid Electricity Distribution 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.
Lydney ranks 1 of 6 towns we cover in Gloucestershire on modelled yield, against a national mean of 886 kWh per kWp. The county runs from 870 to 905, a spread of 35 kWh per kWp. Within Gloucestershire 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 Lydney
There is no school entry for Lydney 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 Lydney.
The nearest education scheme on the record is 22 miles from Lydney, at Keynsham: 150 kWp at Wellsway School, Chandag Road, applicant Bath & West Community Energy, which holds consent and is awaiting construction. That is someone else's application, not ours, and it is here because it shows what Bristol planning has already accepted at an education site. Source: Renewable Energy Planning Database, Q1 2026.
The summer holiday problem for a Lydney school
25.7 percent of the annual output modelled for Lydney 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 14.1 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 4.9 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 6.4 times as much in July as it does in December, and August alone outproduces December by about 5.3 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.
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 National Grid Electricity Distribution pays for the surplus that is left.
We set out the complete version of the term time arithmetic 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 | 24 | 15 | 9 |
| Feb | 15 | 39 | 21 | 18 |
| Mar | 21 | 73 | 49 | 24 |
| Apr | 12 | 106 | 42 | 64 |
| May | 17 | 123 | 67 | 56 |
| Jun | 21 | 126 | 88 | 38 |
| Jul | 11 | 128 | 45 | 83 |
| Aug | 0 | 105 | 0 | 105 |
| Sep | 20 | 82 | 55 | 27 |
| Oct | 17 | 50 | 27 | 23 |
| Nov | 21 | 29 | 20 | 9 |
| Dec | 15 | 20 | 10 | 10 |
| Year | 190 | 905 | 439 | 466 |
Grid connection through National Grid Electricity Distribution
National Grid Electricity Distribution 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 Gloucestershire the planning database records 207 solar schemes totalling 1592 MW, of which 39 are operational (REPD Q1 2026).
How many schools Forest of Dean has
Forest of Dean has 53 open state-funded schools and colleges on the DfE register teaching 10,680 pupils between them. Source: DfE Get Information About Schools.
The split is 45 primary, 6 secondary, 1 special and 1 further education, at an average of 202 pupils a site. A ratio of 7.5 to one tells you where the roof area is. It is not with the 45 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 Lydney roof
The first survey answers three questions at once: what the roofs carry, what they generate against your own timetable, and how a Lydney 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 Lydney schools
- How much would a school roof near Lydney generate?
- Modelled at 905 kWh per kWp a year, a 150 kWp array on a Lydney school models at about 135,800 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 Lydney?
- It goes somewhere, just not into the timetable. 25.7 percent of the Lydney 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 National Grid Electricity Distribution, or a sign the array is too big. We test which before sizing anything.
- Which network operator handles the connection at a Lydney school?
- Applications go to National Grid Electricity Distribution, who run the network across Gloucestershire. 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.
- How many schools are there around Lydney?
- Forest of Dean has 53 open state-funded schools and colleges on the DfE register, with 10,680 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.