Solar Panels & Rooftop Solar Systems

Types

• On-grid (grid-tied) system — connected to the electricity grid with net metering, no batteries. Lowers daytime electricity bills.
• Off-grid system — panels with batteries, for places with unreliable or no grid supply.
• Hybrid system — grid-connected with battery backup, so it keeps supplying during power cuts.
• Solar water pump system — panels run an agricultural or water pump directly.
• Standalone solar panels — individual modules for projects built by your own electrician or EPC contractor.

What to check before buying

• System size in kW, based on roof shadow-free area (about 8 to 10 sq m per kW) and your monthly electricity use.
• Panel type (mono PERC or TOPCon), efficiency, and whether the modules are on the approved list required for subsidy or net metering.
• Inverter capacity and brand, and the warranty terms for panels and inverter separately.
• Structure: galvanised mounting, wind load, roof waterproofing and earthing and lightning protection.
• Net metering, utility approvals and any central or state subsidy, and who handles the paperwork.
• Performance guarantees, monitoring, AMC, cleaning plan and GST invoice.

Common brands include Waaree, Adani Solar, Tata Power Solar, Vikram Solar and Luminous.

Who buys them

Factories, offices, schools, hospitals, housing societies, farms, shops, hotels and contractors.

Frequently asked questions

What size rooftop system do I need?

Divide monthly units used by about 120 to get a rough kW size. Roof area and shading may reduce it.

On-grid or hybrid?

On-grid has lower cost and is ideal if power cuts are rare. Choose hybrid if you need supply during outages.

How long do panels last?

Panels commonly carry performance warranties of 25 years or more, while inverters typically have shorter warranties.