Specialist solar panels for schools in Harrow
Harrow has 61 state-funded schools and colleges, and most of them are buying electricity in exactly the hours their own roofs could be making it. We start with the roof build up and the age of the covering, because across a school estate that is usually what decides which block goes first.
902 kWh per kWp a year at this latitude, so a 170 kWp array, the size applied for at the nearest school scheme on record, models at about 153,300 kWh. Source: EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss.
Book a roof survey in Harrow- 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.
Solar for education buildings across Greater London
A one kilowatt-peak array on a shallow pitched roof in Harrow 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). Harrow 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, 13 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.
Harrow ranks 35 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.
School solar on record near Harrow
No school or college solar scheme appears in Harrow and the area around it in the Renewable Energy Planning Database. That is a reporting threshold rather than a verdict. The database records generating stations from one megawatt upward reliably and smaller ones patchily, and almost every school array is a fraction of that, so a roof full of panels on a Harrow secondary could be generating today without ever reaching it.
Look 13 miles out and there is one: Samuel Ryder Academy in St Albans, 200 kWp, applied for by Scholars Education Trust, which was withdrawn before determination. None of our doing. It is a public planning record, and the nearest evidence available of how an application like yours is treated around here. Source: Renewable Energy Planning Database, Q1 2026.
Term dates against the Harrow generation curve
A Harrow school roof generates most in the weeks its buildings are closed. 25.4 percent of the modelled year lands in July and August alone (EU PVGIS v5.2), and the summer holiday takes roughly six of those nine weeks out of the timetable. July is the single strongest month here at 13.8 percent of the annual total, and it falls almost entirely inside the holiday.
Winter reverses it. December and January between them return 5.3 percent of the modelled year, and that is when the heating, the lighting and a full register are all drawing at the same time. 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.
Put the two calendars together and roughly 49 percent of a school's generation nationally lands on a session day, against about 71 percent for a business open every weekday. That gap is the whole difference between appraising a school roof and appraising any other commercial one, and it barely moves from town to town.
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.
None of that makes a Harrow scheme a bad one. It changes what the scheme should be: sized against the base load that runs whether or not the school is open, which on most sites is servers, comms, catering refrigeration, ventilation and hot water, with lettings, holiday clubs and summer works added on top. Where that base load is thin, the choices are storage, an export arrangement through UK Power Networks, or a smaller array that consumes nearly everything it makes.
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 | 26 | 17 | 9 |
| Feb | 15 | 39 | 21 | 18 |
| Mar | 21 | 74 | 50 | 24 |
| Apr | 12 | 104 | 42 | 62 |
| May | 17 | 119 | 65 | 54 |
| Jun | 21 | 124 | 87 | 37 |
| Jul | 11 | 125 | 44 | 81 |
| 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 | 904 | 443 | 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.
Harrow schools, phase by phase
Harrow has 61 open state-funded schools and colleges on the DfE register teaching 38,452 pupils between them. Source: DfE Get Information About Schools.
The split is 41 primary, 13 secondary, 4 special and 3 further education, at an average of 630 pupils a site. Read 3.2 primaries per secondary as a sequencing hint rather than a statistic. A primary is a single survey visit and a modest array; a secondary is several roofs of different ages on one site, and that is where both the area and the complications are.
A trust holding more than one of these sites should look at them together. Grouping the surveys turns the grid question, the funding question and the procurement route into one exercise rather than four, and it usually changes which roof goes first.
Book a roof survey at your Harrow school
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.
Harrow school solar, answered
- What would a 170 kWp array produce at a Harrow school?
- Yes, and the figure matters more than the sunshine. 902 kWh per kWp a year puts a 170 kWp array at around 153,300 kWh, on roughly 505 square metres of roof. The value of that depends on your term time load. Source: EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss.
- What happens to the electricity during the summer holidays in Harrow?
- Less is wasted than governors expect, but the figure is worth seeing: 25.4 percent of the year is modelled to arrive in July and August here (EU PVGIS v5.2), against a site running on holiday base load. Lettings, holiday clubs and summer works take some of it, storage takes more, and the rest is an export question for UK Power Networks.
- Who do we apply to for export near Harrow?
- Only UK Power Networks can answer it for your connection. What we can say is that a capped export limit rarely breaks a school scheme, because the array that suits a school is sized to the term time load rather than to the roof.
- How many schools are there around Harrow?
- Harrow has 61 open state-funded schools and colleges on the DfE register, with 38,452 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.