Specialist solar panels for schools in Hatfield
UK Power Networks runs the network around Hatfield, 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.
171,200 kWh a year, modelled for a 190 kWp array on roughly 564 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 Hatfield- 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 Hertfordshire
A one kilowatt-peak array on a shallow pitched roof in Hatfield models at 901 kWh a year, from modelled irradiation of 1,155 kWh per square metre in the plane of the array (EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss). Hatfield 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 190 kWp array, sized to what the nearest school scheme on record applied for, 3 miles away at Welwyn Garden City, models at about 171,200 kWh a year before shading, and needs roughly 564 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 43,800 kWh landing in July and August and roughly 8,700 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.
Hatfield ranks 4 of 10 towns we cover in Hertfordshire on modelled yield, against a national mean of 886 kWh per kWp. The county runs from 895 to 911, a spread of 16 kWh per kWp. Within Hertfordshire 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 Hatfield
The AL10 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 Hatfield.
The nearest education scheme on the record is 3 miles from Hatfield, at Welwyn Garden City: 190 kWp at Ridgeway Academy, Herns Lane, applicant Earthpoints Limited, which holds consent and is awaiting construction. That is someone else's application, not ours, and it is here because it shows what Hertfordshire planning has already accepted at an education site. Source: Renewable Energy Planning Database, Q1 2026.
The summer holiday problem for a Hatfield school
25.6 percent of the annual output modelled for Hatfield 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 5.1 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.
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.
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.
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 UK Power Networks pays for the surplus that is left.
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 | 73 | 49 | 24 |
| Apr | 12 | 104 | 42 | 62 |
| May | 17 | 120 | 66 | 54 |
| Jun | 21 | 124 | 87 | 37 |
| Jul | 11 | 125 | 44 | 81 |
| Aug | 0 | 106 | 0 | 106 |
| Sep | 20 | 84 | 56 | 28 |
| Oct | 17 | 51 | 28 | 23 |
| Nov | 21 | 31 | 22 | 9 |
| Dec | 15 | 21 | 10 | 11 |
| Year | 190 | 902 | 440 | 462 |
Grid connection through UK Power Networks
Connections around Hatfield are handled by UK Power 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 Hertfordshire the planning database records 119 solar schemes totalling 844 MW, of which 12 are operational (REPD Q1 2026).
How many schools Welwyn Hatfield has
Welwyn Hatfield has 49 open state-funded schools and colleges on the DfE register teaching 17,056 pupils between them. Source: DfE Get Information About Schools.
The split is 39 primary, 6 secondary and 4 special, at an average of 348 pupils a site. At 6.5 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 Welwyn Hatfield, 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.
Start with the Hatfield 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 Hatfield schools
- How much would a school roof near Hatfield generate?
- Modelled at 901 kWh per kWp a year, a 190 kWp array on a Hatfield school models at about 171,200 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 Hatfield?
- It goes somewhere, just not into the timetable. 25.6 percent of the Hatfield 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 UK Power Networks, or a sign the array is too big. We test which before sizing anything.
- Which network operator handles the connection at a Hatfield school?
- Applications go to UK Power Networks, who run the network across Hertfordshire. 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 Welwyn Hatfield 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 Welwyn Hatfield on siting and design. Listed buildings and conservation areas are the usual exceptions. We put the position to Welwyn Hatfield before a design is finalised.
- How many schools are there around Hatfield?
- Welwyn Hatfield has 49 open state-funded schools and colleges on the DfE register, with 17,056 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.