Read the whole rooftop solar proposal
Understand the path from sunlight to household appliances, the roles of the inverter and meters, and why ordinary grid-connected solar does not provide outage backup. Use that knowledge to ask better questions before installation and commissioning.
In this article
- Follow the energy from panels to appliances
- Understand capacity, energy and ordinary variation
- Distinguish generation, import and export readings
- Know why ordinary grid-connected solar stops in an outage
- Treat roof suitability as an engineering question
- Follow the current application and approval route
- Ask for a usable commissioning and handover file
- Maintain performance and recognise faults
- Sources & further reading
Follow the energy from panels to appliances
Photovoltaic modules convert sunlight into direct-current electricity. An inverter converts that output into alternating current compatible with the home and the distribution network. Cables, protective devices, mounting structures and the connection arrangement complete the system. The roof panels are therefore only one part of the installation. A proposal showing the module brand without explaining the inverter, protection and wiring leaves important questions unanswered.
In a typical grid-connected arrangement serving the home, solar energy can support appliances while it is being produced. If demand exceeds available solar output, the shortfall comes from the grid. If generation exceeds demand and the approved arrangement permits it, surplus flows to the grid. The balance changes throughout the day with clouds and household use. Electricity does not wait inside the panel for the evening unless a separate storage system captures some of it.
Section references: [1]
Understand capacity, energy and ordinary variation
Kilowatts describe power at a moment or a rated capacity, while kilowatt-hours describe energy accumulated over time. One kilowatt supplied continuously for an hour is one kilowatt-hour, commonly called one unit on an electricity bill. A three-kilowatt rated array does not promise three kilowatts every daylight hour. Output depends on sunlight, cell temperature, orientation, shading and the rest of the system.
Ask whether the quoted array capacity is the modules’ DC rating and what AC inverter capacity is provided. A system design can involve different DC and AC ratings for legitimate reasons, but the vendor should explain the choice. Shading from a tank or neighbouring structure can have an important effect, so a clear roof photograph alone is insufficient. Obtain a site survey and an energy estimate with assumptions rather than relying on the capacity label.
Distinguish generation, import and export readings
The inverter commonly displays generated energy, while a bidirectional utility meter records energy flowing to and from the grid. The home may consume some generated electricity immediately, so generation and export are different quantities. For an illustrative hour, generation of two units and household use of one unit leaves roughly one unit available for export before considering system and measurement details. At night, without suitable storage, household demand is supplied by the grid.
Use the DISCOM’s commissioning documents to identify the meters and readings that matter for billing. A generation dashboard is useful for performance, but it does not itself determine the utility’s settlement. Billing periods, meter registers and credit rules can differ from a calendar-month inverter chart. Keep screenshots and bills with matching dates when investigating a discrepancy, and avoid resetting or altering metering equipment to make the numbers appear consistent.
Know why ordinary grid-connected solar stops in an outage
A standard grid-connected inverter stops feeding electricity when the grid supply fails. This anti-islanding function helps protect people working on the network and prevents uncontrolled operation of the disconnected supply. The fact that sunlight remains available does not mean the home will continue receiving power from that ordinary configuration. A seller should explain this behaviour before the household assumes solar will solve frequent outages.
Backup requires an appropriately designed arrangement, potentially including compatible storage, controls, transfer equipment and a separate essential-load circuit. Not every inverter can be converted to provide backup by adding a battery later. Ask which appliances can run, at what combined power and for what expected duration under stated conditions. Never bypass anti-islanding or improvise a connection to an ordinary household backup inverter; integration needs qualified design and approval.
Section references: [1]
Treat roof suitability as an engineering question
Confirm roof ownership or use rights, access and the permissions needed from an owner or society. Assess the condition of the roof, mounting arrangement, wind exposure and waterproofing. Keep routes to tanks, drains and service equipment accessible. An elevated structure may change loads and permissions, so it needs more than a promise that the installer has used the same design elsewhere. Document responsibilities if the roof later leaks.
The electrical design should address earthing, surge and fault protection, safe cable routing, isolation and the approved grid connection. These are qualified tasks. Solar DC circuits can remain energised in sunlight even when a household AC switch is off, so residents should not open connectors or assume every part is dead after switching off the inverter. Ask the installer to label equipment and explain which user actions are permitted during a fault.
Follow the current application and approval route
For residential support under PM Surya Ghar, begin with the official national-portal and DISCOM process applicable to the connection. Verify the current eligibility, equipment conditions, registered-vendor arrangements and sequence before purchase. Rules and implementation can change, so an old subsidy table or another state’s approval letter is not sufficient. Keep control of the household’s login and documents rather than handing unrestricted access to a sales intermediary.
Request a written plan showing application, technical feasibility where required, installation, inspection, metering and commissioning responsibilities. A plant physically fixed to the roof is not necessarily authorised to export or eligible for financial assistance. Keep invoices, component details and application acknowledgements together. When a vendor promises to handle everything, ask which tasks still require the consumer’s confirmation and what evidence shows that each utility stage has been completed.
Ask for a usable commissioning and handover file
At handover, obtain the approved equipment list, serial numbers, warranties, installation drawings, test and commissioning records, and the service contact. Ask for a plain explanation of the normal startup and shutdown procedure, fault indicators and isolation points the consumer may operate. Verify that the owner can access monitoring without relying permanently on the installer’s personal account. Keep passwords private and change any temporary credentials through the supported process.
Review the first available bill and compare import and export registers with the commissioned arrangement. Record a normal day’s monitoring values as a reference without treating it as the annual average. Clarify the response time for faults, whether remote monitoring is included and who pays for visits outside warranty. Good handover makes the system understandable to the household even if the original salesperson changes jobs.
Maintain performance and recognise faults
Inspect performance trends through the approved monitoring interface. An unexpected prolonged drop deserves investigation, but a cloudy day is not automatically a fault. Look for obvious new shade from a safe location and report alerts with dates and screenshots. Cleaning frequency depends on local dust, rainfall and the equipment instructions. Use a safe professional route where roof access or electrical exposure creates risk rather than climbing onto modules to reach the far side.
Keep water away from unsuitable electrical equipment and do not handle damaged cables, cracked modules or loose connectors. After storms, roof work or visible damage, obtain inspection before assuming continued operation is safe. Review the system annually against its original aims and records. Savings are assessed from actual generation, use and billing rules; a dashboard’s impressive total is useful evidence only when the household understands what it measures and what costs remain.
Readers’ questions
Can I switch off the mains and use solar during a power cut?
Ordinary grid-connected solar is designed to stop during grid failure, and switching a household main switch does not automatically create an approved backup system. A suitable backup design needs compatible controls, protection and separation from the grid. Ask the installer for the exact supported outage behaviour. Never bypass anti-islanding or connect equipment in a way intended to fool the inverter.
Does a net meter store electricity for nighttime use?
No. A meter records energy flows; it is not a battery. Under the applicable settlement rules, exports may create credits or other accounting benefits, but the electricity used at night still comes from an available supply. The value and duration of credits depend on local provisions. Physical backup and bill accounting are separate questions and should be explained separately in a quotation.
Can I clean panels myself with a hose?
Only within the equipment instructions and a genuinely suitable access arrangement. Wet roofs, height, electrical equipment and damaged surfaces introduce risks. Do not stand on panels, open connectors or spray unsuitable components. For many homes, an agreed professional maintenance route is more practical. Ask the installer to specify the cleaning method, access requirements and exclusions before commissioning rather than discovering them when output falls.
Sources & further reading
- FAQs on Grid Connected Solar Rooftop Systems — MANIREDA; technical explanations only ↗
- Standards & Labelling Programme — Bureau of Energy Efficiency ↗
- Citizen’s Charter, March 2026: How Your Bill Is Prepared — BSES ↗
- Rooftop Solar Installation Process for Consumers — Delhi EEREM ↗
- Operational Guidelines: Central Financial Assistance to Residential Consumers — MNRE ↗
Sources were checked for this edition. Scheme rules, product conditions and local requirements can change; consult the responsible provider for a decision.
