Specialist solar panels for schools in Caernarfon

Solar PV for academy trusts across Gwynedd

A one kilowatt-peak array on a shallow pitched roof in Caernarfon models at 798 kWh a year, from modelled irradiation of 1,019 kWh per square metre in the plane of the array (EU PVGIS v5.2, SARAH3, 10 degree pitch, 14 percent system loss). 10 percent below our mean puts Caernarfon at the weaker end of the range, which raises the premium on self consumption and lowers the value of anything that leaves the site.

Scaled up, a 380 kWp array, sized to what the nearest school scheme on record applied for, 67 miles away at St Helens, models at about 303,200 kWh a year before shading, and needs roughly 1,129 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 77,300 kWh landing in July and August and roughly 11,800 kWh across December and January. SP Energy 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.

The planning position for Caernarfon schools

No school or college solar scheme appears in Caernarfon 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 Caernarfon secondary could be generating today without ever reaching it.

The closest recorded one is about 67 miles away at St Helens: The Sutton Academy, Elton Head Road, a 380 kWp roof mounted array applied for by Located Property Limited, which holds consent and is awaiting construction. We were not involved in it. We cite it because it is a public record of what has cleared planning in this part of Merseyside. Source: Renewable Energy Planning Database, Q1 2026.

Why demand in Caernarfon falls as the roof peaks

The generating year and the school year are out of step in Caernarfon. July and August carry 25.5 percent of the modelled output (EU PVGIS v5.2), and the site is closed for most of those nine weeks. May is the strongest single month here at 14.7 percent of the annual total, which is still term time, and that works slightly in your favour against towns whose curve peaks in July.

At the other end of the year the mismatch flips. Only 3.9 percent of output falls in December and January, the two months when a Caernarfon school is fully occupied and its heating and lighting are at their heaviest. The roof makes 9 times as much in May as it does in December, and August alone outproduces December by about 7.2 to one. 76 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.

Daily shape compounds it. A school's load climbs from breakfast club, holds through the teaching day and falls away from about three in the afternoon, while generation is still strong until six in high summer. That is why we size against half hourly meter data rather than against annual consumption: the annual figure hides both problems.

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 SP Energy Networks pays for the surplus that is left.

We set out the full treatment of the school year against the generation curve on the home page, and what it does to a payback figure under costs.

Grid connection through SP Energy Networks

SP Energy 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 Gwynedd the planning database records 19 solar schemes totalling 221 MW, of which 6 are operational (REPD Q1 2026).

What Caernarfon trusts ask before a survey

How much would a school roof near Caernarfon generate?

Modelled at 798 kWh per kWp a year, a 380 kWp array on a Caernarfon school models at about 303,200 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 Caernarfon?

It goes somewhere, just not into the timetable. 25.5 percent of the Caernarfon 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 SP Energy Networks, or a sign the array is too big. We test which before sizing anything.

Which network operator handles the connection at a Caernarfon school?

Applications go to SP Energy Networks, who run the network across Gwynedd. 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.