Solar system for a school in Lahore

A school load is boring, and that is the point

Ask a Lahore school administrator what runs on the campus and the answer is short. Ceiling fans. Tube lights. Two or three ACs in the principal's office and the computer lab. A water pump. A bell. Maybe a sound system for assembly.

Nothing surges. Nothing runs at 2 am. The load switches on around 7:45 and switches off around 2:15, then a caretaker keeps a few lights going. For a solar designer that is close to ideal, because a flat daytime load with no evening tail can be covered almost entirely by an on-grid array with no storage at all.

The other advantage is roof. School buildings in Lahore are usually two or three storeys with a long, plain, unshaded slab over the classroom block, plus a covered assembly area that takes an elevated structure well. Compare that with a 10 marla house that has three tanks and a stair block in the way.

Counting the load properly

Schools get undersized more often than any other building type, because whoever quotes counts the ACs and forgets the fans. A ceiling fan draws 75 to 110 watts. Twenty classrooms with four fans each is 80 fans, roughly 7 kW running continuously from March to October.

Add the lighting. Old 40W tube lights in a 20-room block are another 3 kW. Swapping those to LED before the solar quote is written saves roughly 2 kW of array, which is PKR 200,000 of panels and structure not bought. That conversation should happen at survey.

Campus size	Typical daytime load	Monthly units	Recommended system	Turnkey cost
Primary, up to 200 students	6 - 9 kW	1,400 - 2,000	10 kW on-grid	PKR 1,250,000 - 1,450,000
Single campus, 300 - 500 students	11 - 16 kW	2,600 - 3,600	15 kW on-grid	PKR 1,850,000 - 2,100,000
Campus with labs and 6 ACs	17 - 23 kW	3,800 - 5,200	20 kW on-grid	PKR 2,400,000 - 2,750,000
Large school, 800+ students	25 - 34 kW	5,600 - 7,500	30 kW on-grid	PKR 3,500,000 - 4,000,000

Component rates used: 645W bifacial panel PKR 21,000, 585W Tier-1 PKR 19,500, mounting PKR 7,000 per kW on the slab and PKR 12,000 per kW where the structure is elevated over an assembly area or car park, electrical items kit PKR 35,000, wiring PKR 25,000, installation labour PKR 20,000, LESCO net metering paperwork PKR 15,000. A campus of 20kW and above is almost always three-phase.

The summer holiday question

Every school administrator asks it. June and July are the strongest generation months in Lahore, and the campus is shut. Is that money wasted?

Not wasted, but not worth as much as the school hopes. With net metering in place, the array keeps generating and exports to LESCO. Those units are credited against the bill at the buyback rate, which sits well below the retail rate the school pays for consumption. So a month that would have saved PKR 260,000 through direct consumption instead returns something closer to PKR 60,000 to 90,000 as export credit.

Two things make that better. First, most Lahore schools do not fully shut. Summer camps, admissions offices, examination work and office staff keep a real load running through the holidays. Second, the credit carries forward on the bill, so it offsets September and October consumption when the fans are back on.

The design implication: do not oversize a school array on the assumption that holiday export pays. Size it to the term-time daytime load. The current rules are explained in net metering changes for 2026, and the application handling is on net metering service.

Whose name is on the meter

This trips up more school projects than any technical issue. Net metering requires the connection to be in the applicant's name, and the sanctioned load must be at least the inverter capacity.

Three common situations in Lahore:

1. School owns the building, meter in the school or trust name. Straightforward. Apply with registration documents, the last paid bill, CNIC of the authorised signatory, and the installer's test report.
2. School rents the building, meter in the landlord's name. Needs a written consent letter from the owner and usually a longer lease. Without it, LESCO will not process the application, and the school should not fund a system it may have to remove.
3. Sanctioned load lower than the planned inverter. A load extension application goes in first. Four to eight weeks at the subdivision office, plus a security deposit.

Where net metering is genuinely unavailable, a school can still run a self-consumption system with export blocked at the inverter. It works, it saves during teaching hours, and it just gives up the holiday credit. That route is described in solar without net metering.

Does a school need a battery

Mostly no. The honest downside of adding storage to a school is that it buys comfort during a few outage hours per week at a cost of PKR 285,000 for a 5 kWh lithium bank, money that would buy roughly 14 more panels and generate every single day.

There are exceptions worth funding:

• A server, biometric attendance system and CCTV recorder. A 2.5 kWh lithium at PKR 130,000 to 145,000 on a protected circuit covers these.
• A boarding or hostel block, which has a genuine evening and night load. That is a separate hybrid design, not an extension of the classroom system.
• Examination halls during board exams, where a two hour outage in June is a real operational failure.
• A campus in an area with poor LESCO feeder reliability, where mid-morning trips are frequent rather than occasional.

If storage is going in, lithium is the right call for a campus. Tubular banks need ventilation, water top-ups and a locked room away from children, and the ten year cost lands higher. Reasoning in lithium versus tubular and sizing in battery bank sizing. Design help is on hybrid and battery, and the pure daylight build on on-grid solar.

Safety and layout on a campus roof

Access control

Children will get to the roof. Assume it. Every DC junction box needs a lockable enclosure, all cable runs need conduit rather than exposed clips, and the roof access stair needs a lock that is actually used. Inverters should be mounted in a plant room or a locked cage, never on an open wall in a corridor.

Structure over play areas

Elevated structures over an assembly ground or car park work well and shade the area below, which is a genuine benefit in a Lahore May. They cost PKR 12,000 per kW instead of PKR 7,000, and they need proper foundations, not ballast blocks, because a cricket ball and a strong pre-monsoon gust are both routine on a school ground.

Install timing

Do the installation during summer holidays or winter break. A 20kW job takes four to six days with drilling, crane lifts and live electrical work, none of which belongs on a working campus. Scope is on installation service.

A worked example from a Lahore campus

A private school off Wahdat Road, 480 students, two teaching blocks, 26 classrooms, a computer lab with 24 machines and two ACs, an office block with three ACs, two water pumps. Three-phase connection. Twelve month average of 3,400 units, summer peak 4,900 units, average monthly bill around PKR 205,000.

Installed: 20 kW of 645W bifacial modules, part on the block-B slab and part on an elevated frame over the parking strip, one 20kW three-phase on-grid inverter, net metering approved eight weeks after commissioning. Total cost PKR 2,620,000.

Generation runs 2,500 to 3,000 units a month in term time, almost all consumed. Term-time bills dropped to PKR 45,000 to PKR 78,000. June and July, with the campus on skeleton staff, produced an export credit averaging PKR 71,000 a month. Annual saving worked out near PKR 1,120,000, giving payback around 28 months.

The part that annoyed the administration: for six weeks between commissioning and the net meter, the system ran in zero-export mode and the holiday generation was simply lost. Applying two months before the planned install date avoids that. Similar sizing comparisons sit in 15kW pricing and installation cost in Lahore 2026.

Keeping the array working through the year

School roofs go unwatched during holidays, which is exactly when a fault costs the most. Basic discipline: monitoring app checked weekly by the admin officer, panels cleaned monthly through smog season and six-weekly otherwise, and one inspection right after the first monsoon downpour. Rates on cleaning cost, service on panel cleaning, and fault work through repair.

Winter is the weak season here. Expect December and January output 25 to 35 percent below the annual average because of smog and short days, detailed in winter solar output in Lahore. Budget the school's cash flow around that rather than being surprised by a January bill.

Campuses across Johar Town, Model Town, Wapda Town, Bahria Town and DHA are all within regular working range. Start with a rough figure on the calculator, then get in touch through contact.