Coimbatore School Solar: 25 kW Planning Scenario

Illustrative planning scenario, not a customer case study. The 25 kW capacity is a working brief, not a recommendation. This page is not based on a signed customer record, site survey, interval load file, design, quotation, commissioning report or measured performance dataset. Every project outcome is therefore unknown.

A school load changes across teaching days, holidays, examinations and events. This scenario shows how to test a 25 kW working brief without pretending that one timetable, tariff or roof applies to every campus.

What decision does this scenario test?

The question is not whether 25 kW “works” in the abstract. The question is whether that AC capacity, paired with a documented PV array and connection design, fits the site’s measured daytime load, available area, electrical infrastructure and approval route.

A credible answer must be electrically safe, acceptable under the current project process, and commercially supportable after every cost and uncertainty is shown.

Evidence required before sizing

A missing input should stay marked as unknown. Replacing it with a typical value creates a neat result but not a reliable decision.

Engineering controls for this site

• Separate occupied-area safety requirements from energy-generation objectives.
• Plan safe isolation, locked access, signage and maintenance routes.
• Model holidays and low-load days so exports are not hidden inside an annual average.

Tax treatment differs by legal entity and cannot be inferred from the words school or trust.

The responsible electrical professional should sign the single-line diagram, protection settings and commissioning plan. Any safety-critical or production-critical system needs an independent continuity plan.

How should the commercial case be calculated?

Use measured inputs and keep the calculation reproducible:

1. Estimated annual generation = simulation output for the documented array, orientation, losses and weather dataset.
2. Self-consumed energy = the lesser of generation and coincident site load in each interval.
3. Exported energy = generation minus self-consumed energy, subject to the approved metering arrangement.
4. Annual bill effect = avoided import charges plus documented export credit minus fixed, demand, finance, service and maintenance costs.
5. Simple payback = eligible project cost divided by annual net cash benefit.

Do not publish a generation, saving, return or payback result until the calculation file identifies every input, unit, date and source. Tax effects require written advice from a qualified professional. Financing results require actual lender terms.

What can be said about Qbits equipment?

Qbits’ published catalogue lists on-grid and hybrid inverter families with model-specific ratings. That does not prove that a Qbits model is suitable for this scenario. Nor does it state universal battery compatibility, transfer time, monitoring functions, harmonic performance, certification, warranty terms, service coverage or project support.

If Qbits is shortlisted, record the exact SKU and request its current datasheet, installation manual, applicable certificates, monitoring scope, written warranty and service terms. Compare those documents with the final design. MNRE’s current ALMM page concerns PV module and cell lists, not an inverter list.

What belongs in the handover record?

Keep approved drawings, the final equipment schedule, utility correspondence, protection settings, test results, commissioning readings, photographs, monitoring ownership, invoices, warranties and service contacts.

The EPC bid checklist helps compare proposals. The commissioning guide covers handover evidence. For a Qbits equipment enquiry, use the datasheet library and contact page.