A day school switches off at four in the afternoon, which makes it an unusually good match for rooftop solar. The limits are the roof structure, the sanctioned load and the missing maintenance budget.
A day school switches on around eight in the morning and empties by four in the afternoon. Nearly all of its electricity is spent in the hours when a rooftop array is generating, which is a better match than a hospital, a hotel or most factories will ever manage. That single fact makes school solar unusually easy to justify and unusually easy to get wrong, because the things that sink these projects are not the energy arithmetic. They are the roof, the sanctioned load and the fact that nobody funded the cleaning.
Walk a school at eleven in the morning and count what is running: ceiling fans in every classroom, tube lights on cloudy days, a computer lab, the office air conditioner, a water pump filling the overhead tank, and in larger schools a few classroom air conditioners. All of it is daytime. There is no night shift, no cold store, no standing load to speak of after the guard's light.
That means a well sized school array is consumed almost entirely on site. Self consumption is where the value sits, because a unit you consume behind your own meter displaces the retail tariff, while a unit you export is settled on the terms in the net metering agreement. A school is one of the few consumer types in Bangladesh that can approach full self consumption without any battery at all.
Residential madrasas are a different animal and should be surveyed as such. A hifz madrasa with boarding students has lighting and fan load before Fajr and again after Maghrib, kitchen load in the evening, and pumping at both ends of the day. The generation curve still helps, but the flat daytime match that makes a day school so straightforward is not there, and the sizing should follow the measured load rather than the roof area.
On paper a three storey school block has plenty of roof. On site, after you subtract the overhead water tanks, the stair head, the parapet setback, the space the school uses for assembly or for drying, and the shadow of the tank on the array, the usable area falls sharply. Measure it with a tape and mark it out, because the difference between drawn area and usable area on a school roof is routinely a third.
Schools close for weeks at a time. Add the annual vacation, the Ramadan and Eid closures, public holidays and examination gaps, and a meaningful part of the year has almost no daytime load while the array keeps generating into the grid.
This is the single strongest argument against oversizing a school plant. Every extra kWp added beyond the school's own daytime consumption spends the holidays producing units that are settled rather than consumed, and the settlement terms are not the retail tariff. Size to the term time daytime baseline, not to the roof, and put the money you saved into a better structure and a maintenance contract.
School and madrasa projects are usually paid for in one go: an alumni collection, a single donor, a company's social spending, a waqf or zakat contribution, the upazila education office, or a managing committee that has saved for two years. The money arrives once, it buys equipment, and everybody is photographed on the roof.
Then nothing is budgeted for year two. This is why so many donated systems in Bangladesh are underperforming or dead within a few years, and it is a funding design fault rather than a technology fault.
Net metering is granted to the holder of the electricity connection, and the plant is capped against that connection's sanctioned load. Two practical consequences follow. First, the application has to be made in the institution's name as it appears on the bill, and if the connection is still in the name of a founder or a former headmaster, that has to be corrected before anything else happens. Second, a school on a small single phase connection cannot install a large array no matter how much roof it has, and the honest answer may be to apply for a load increase first, or to build to the ceiling and stop.
Rural schools and madrasas supplied by the rural electrification network follow the same route through their own utility office, and it is worth asking early which office holds the file, because a rejected application returned after two months is usually a rejected form rather than a rejected project.