How much would a school roof near Weymouth generate?

Modelled at 1,006 kWh per kWp a year, a 590 kWp array on a Weymouth school models at about 593,500 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 Weymouth?

It goes somewhere, just not into the timetable. 26 percent of the Weymouth 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 Weymouth school?

Applications go to Scottish and Southern Electricity Networks, who run the network across Dorset. 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 Dorset 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 Dorset on siting and design. Listed buildings and conservation areas are the usual exceptions. We put the position to Dorset before a design is finalised.

How many schools are there around Weymouth?

Dorset has 155 open state-funded schools and colleges on the DfE register, with 44,528 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.

Specialist solar panels for schools in Weymouth

A school roof in Weymouth makes 6.2 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.

593,500 kWh a year, modelled for a 590 kWp array on roughly 1,752 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 Weymouth

1 teaching block
2 hall and kitchen
3 sports hall
4 1960s block, no array
first phase
later phase

Drawing Illustrative estate, not a Weymouth school

Blocks 4, 3 with array

Array about 345 kWp

Yield about 347,000 kWh/yr

Frontage about 90 m / Rev A / DT3

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.

Weymouth / Dorset

A school on the edge of a South West market town, solar arrays on its roofs and rolling farmland beyond — School buildings of the kind we survey across South West. Not a named school and not our work.

School rooftop solar across Dorset

A one kilowatt-peak array on a shallow pitched roof in Weymouth models at 1,006 kWh a year, from modelled irradiation of 1,289 kWh per square metre in the plane of the array (EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss). That is around 14 percent above the mean across the towns we cover, which is about as strong as a UK school roof gets.

Scaled up, a 590 kWp array, sized to what the nearest school scheme on record applied for, 5 miles away at Dorchester, models at about 593,500 kWh a year before shading, and needs roughly 1,752 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 154,300 kWh landing in July and August and roughly 29,700 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.

FIG. 1 Weymouth against the rest of Dorset

Weymouth1006
Dorchester985
Christchurch981
Bournemouth971
Bridport971
Poole965
Wimborne964
Sherborne924

Weymouth ranks 1 of 8 towns we cover in Dorset on modelled yield, against a national mean of 886 kWh per kWp. The county runs from 924 to 1006, a spread of 82 kWh per kWp. On a 500 kWp array that is about 41,000 kWh a year between the strongest and weakest town in the county.

Bars are zero based, so length is proportional to the figure. Where a county is flat, that is the finding: latitude is not the lever, the timetable is. Source: EU PVGIS v5.2, modelled per town

What the planning record shows around Weymouth

There is no school entry for the DT3 postcode district 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 Weymouth.

The nearest education scheme on the record is 5 miles from Weymouth, at Dorchester: 190 kWp at Damers First School, applicant Solar Options for Schools Limited, which holds consent and is awaiting construction. That is someone else's application, not ours, and it is here because it shows what Dorset planning has already accepted at an education site. Source: Renewable Energy Planning Database, Q1 2026.

The summer holiday problem for a Weymouth school

26 percent of the annual output modelled for Weymouth 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 5 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 6.2 times as much in July as it does in December, and August alone outproduces December by about 5.2 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 Weymouth as anywhere else.

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.

The conclusion is not that a Weymouth 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.

FIG. 2 A Weymouth roof against the English school year

generated while the school is open
generated at a weekend or in the holidays

The same figures as a table

Monthly output for a 1 kWp array in Weymouth, split by whether the day is a school session day. Across the year 49 percent of generation lands while the school is open.
Month	Session days	Output, kWh per kWp	School open	School closed
Jan	20	27	17	10
Feb	15	43	23	20
Mar	21	81	55	26
Apr	12	117	47	70
May	17	136	75	61
Jun	21	139	97	42
Jul	11	142	50	92
Aug	0	119	0	119
Sep	20	91	61	30
Oct	17	54	30	24
Nov	21	33	23	10
Dec	15	23	11	12
Year	190	1005	489	516

Per kWp installed, month by month, separating generation while the school is open from generation at a weekend or in the holidays. 74 percent of the Weymouth year sits between April and September, most of which is term time; it is the tail of that period, the last week of July and all of August, that the school is not there for. The daily split is a flat apportionment of each month, not a metered one. Session days follow a typical English school year of 190 days. Your own trust or authority may differ by a few days either way. Source: EU PVGIS v5.2, session days from a typical school calendar

How many schools Dorset has

Dorset has 155 open state-funded schools and colleges on the DfE register teaching 44,528 pupils between them. Source: DfE Get Information About Schools.

The split is 119 primary, 29 secondary, 6 special and 1 further education, at an average of 287 pupils a site. A ratio of 4.1 to one tells you where the roof area is. It is not with the 119 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.

Aerial view of a school site with teaching blocks of several different ages, a sports hall and a playing field, solar arrays on two of the flat roofs — A school site with blocks of several ages, which is the usual starting point for a trust estate survey.

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 Dorset the planning database records 149 solar schemes totalling 1078 MW, of which 47 are operational (REPD Q1 2026).

Book the survey

Start with the Weymouth roof

Roof condition decides the order of works on most school estates, so that is where we start. Send us the postcode and a rough roof area, with twelve months of half hourly readings if you have them, and we come back with usable area, modelled output against your own load, and the funding routes.

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 Weymouth schools

How much would a school roof near Weymouth generate?: Modelled at 1,006 kWh per kWp a year, a 590 kWp array on a Weymouth school models at about 593,500 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 Weymouth?: It goes somewhere, just not into the timetable. 26 percent of the Weymouth 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 Weymouth school?: Applications go to Scottish and Southern Electricity Networks, who run the network across Dorset. 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 Dorset 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 Dorset on siting and design. Listed buildings and conservation areas are the usual exceptions. We put the position to Dorset before a design is finalised.
How many schools are there around Weymouth?: Dorset has 155 open state-funded schools and colleges on the DfE register, with 44,528 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.

Nearby

All Dorset locations