Rooftop Solar for Schools, Clinics and Institutions

Why institutions suit solar

Schools, colleges, clinics, hospitals, hostels, offices and trusts mostly run during daylight. Lights, fans, computers, laboratory equipment and cooling are all in use at the same time the panels produce power. Using solar energy as it is generated is the simplest and most efficient way to cut the electricity bill, since it needs no batteries and loses very little on the way.

Institutional buildings also tend to have large, open, flat roofs with few owners to coordinate, unlike a crowded residential block. A school or a hospital building often has several hundred square metres of usable terrace. That makes it easier to fit a system of useful size, and a lower cost per kilowatt than a very small home system is common, though prices vary by supplier and site.

Schools and charitable institutions get another benefit: a visible solar plant can teach students how energy works. This article is general information, not engineering or financial advice. Each building has its own load and structure, so a site survey by qualified people is essential.

Start with the bills and the load pattern

Collect twelve months of electricity bills and note units, tariff category, fixed or demand charges and the sanctioned load or contract demand. Then study when the building uses power. A school may close in summer vacation and have lower use in May and June, the months of highest solar output, while a hospital runs all through the year, day and night.

A school that is shut for weeks in summer will export more during the vacation and use less solar directly in those weeks. Under net metering, exported units are credited against later use under the rules that apply, but settlement terms can change, so size the system on realistic daily use. A hospital, with steady daytime use, can usually use most of its solar output directly.

Ask the installer to look at your actual consumption by month and by time of day, if your meter records it. Interval data helps match solar output to the load more precisely, and is worth requesting from the DISCOM for larger connections.

Plan critical loads separately

Some loads cannot go down when the grid does. In a hospital or clinic, ICU and ventilator equipment, operation theatres, vaccine and blood refrigeration, oxygen concentrators and emergency lighting need uninterrupted power. A standard grid-connected solar system shuts down during a grid outage for safety, so it does not protect these loads on its own.

Use solar to cut the bill and design backup separately. Backup normally comes from an uninterruptible power supply, batteries, a diesel generator or a combination, designed by a qualified electrical engineer and, where applicable, in line with healthcare facility rules. Solar-plus-battery systems can supply part of the backup, but they must be engineered for the specific critical load, not sold as a general solution.

Never connect critical equipment to a new supply arrangement without the advice of the person responsible for the facility's electrical safety. If you run a healthcare facility, check with the relevant authority about requirements for backup power and electrical safety.

Tariff, sanctioned load and approvals

Institutional connections usually fall under a different tariff category from homes, with their own rates and charges. Subsidies for residential households, such as the central subsidy under PM Surya Ghar, do not apply to institutional or commercial connections. Check with your installer and the relevant department whether any separate scheme, grant or programme applies to your institution at present, and ask for the notification in writing.

As with other grid-connected systems, you will need DISCOM approval, an inspection and a net meter, and the system size is generally linked to your sanctioned load. Larger connections may follow more detailed technical rules. Ask the installer to manage the paperwork and give you copies of every approval.

Government schools, aided institutions and trusts may also need internal approvals, such as a management resolution, a department's permission or a tender procedure. Start these early, since they can take longer than the installation itself.

• Twelve months of bills, tariff category and sanctioned load.
• Proof of ownership or authority over the roof, or a no-objection letter.
• Management or department approval, where required.
• DISCOM application, inspection report and net meter details.
• A written warranty, service contract and commissioning report.

Roof, structure and safety on a busy campus

Before panels go up, a qualified civil or structural engineer should check the roof for load, waterproofing and wind exposure, as explained in our roof assessment checklist. Old school buildings and shared hospital blocks may have weak or leaking terraces, and repairing them first is far cheaper than lifting a plant later.

Many people are on the premises, so safety needs extra care. Keep students and visitors away from the roof, fit edge protection and lock the roof access. Make sure earthing and lightning protection are done properly, as large metal arrays on high buildings can attract lightning. Our guide on earthing and lightning protection describes what to ask for. Panels should also be placed so that they do not block fire exits, water tanks access or rooftop fire-fighting routes.

In hospitals, plan the cable routes and the inverter room carefully, away from areas with flammable gases, oxygen storage or sensitive equipment. Use fire-rated cables and follow the building's fire safety rules.

Choosing a system size and type

A practical approach is to size the plant for the daytime load on normal working days, subject to roof area and sanctioned load, and not to the full monthly use. Many institutions choose an on-grid system, since it is the lowest cost and has little upkeep. Others add a hybrid inverter and a battery for specific essential loads, such as emergency lighting, computers or a small clinic area.

Ask for at least two or three proposals with a clear bill of materials, brand and model numbers, warranty terms, the expected generation per year and the assumptions behind the savings. For a larger plant, ask the installer to show a layout drawing, a shade analysis and single-line diagram. Compare them line by line, not only on price. Our article on common mistakes when buying rooftop solar lists the traps.

Maintenance, monitoring and record keeping

Large arrays collect dust, bird droppings and leaves, and a school near a road or a hospital near a market will see output fall quickly without cleaning. Agree who cleans, how often and with what method, using soft water and a soft brush without harsh chemicals. Our guide on cleaning panels in dusty regions gives a practical schedule.

Keep a simple daily or weekly log of units generated, the weather and any faults. A sudden drop on a clear day is the earliest sign that something needs attention. Ask the installer for a monitoring app or a data logger, and for a service contract that covers regular inspection of the structure, earthing, cables and inverter. Keep the invoices, serial numbers, warranty papers and commissioning report in a file that the next administrator can find.

• Name a responsible person and a backup person for cleaning and logging.
• Agree a service contract with response times in writing.
• Check structure bolts, earthing and cable condition at least once a year.
• Keep a record of generation to support any warranty claim.

Funding and procurement for institutions

Institutions can pay in several ways: from their own funds, from a donation or grant, or through a financing arrangement or a service model where a company installs and the institution pays for the energy. Each has trade-offs. Own funding is simplest and gives you full ownership. Grants may come with conditions on equipment and reporting. Service models can reduce upfront cost but tie you to a long contract, so read the terms, the tariff and the exit conditions carefully, and take legal advice before signing.

Public institutions often follow tender rules. Ask your procurement office what applies, and make sure specifications are written clearly so that suppliers quote on the same basis. Ask any seller who claims a financing partnership or subsidy to show the official document that supports it.

For a site visit and a written quotation for your school, clinic or office, use the quotation form on our home page and we will call you back.