Two things make rooftop solar work financially in Kerala: a central subsidy that reduces what you pay upfront, and net metering that pays you back for what you export. They are separate mechanisms with separate paperwork, and understanding both makes it much harder to be misled by a quote.
Scheme rules and rates do change. Everything below reflects the position at the time of writing, and the official scheme portal is the authority worth checking before you commit.
The subsidy: PM Surya Ghar
The central government's PM Surya Ghar: Muft Bijli Yojana provides a subsidy for residential rooftop systems, paid as a direct bank transfer after your system is installed and commissioned. It is not a discount the installer applies — the money comes to you.
The amount is tiered by system capacity. At the time of writing it is in the region of ₹30,000 for a 1kW system, ₹60,000 for 2kW, and ₹78,000 for 3kW and above, with the 3kW figure acting as a cap rather than scaling further with size.
That tiering has a practical consequence worth thinking about: the step from 2kW to 3kW carries a larger subsidy increase than the step beyond 3kW, so it is worth running the numbers on capacity rather than defaulting to the smallest system that covers your usage.
Net metering: how the bill actually settles
Net metering replaces your existing meter with a bi-directional one that counts import and export separately. During the day your panels supply your loads, and any surplus is exported. At night you import from the grid as usual. Your bill is settled on the net of the two.
This is why sizing against your real consumption matters. Export is credited, but the economics generally favour using your own generation directly rather than exporting it and buying it back. A system sized well beyond your consumption ties up capital for a smaller return.
- A bi-directional meter counts import and export separately
- Daytime surplus offsets night-time consumption
- Sizing follows your actual bills, not a round number
- Self-consumption is generally worth more than export
The sequence to expect
The process runs in a fairly predictable order, and knowing it helps you tell a realistic timeline from an optimistic one.
- Register and apply, with your consumer details and recent bills
- KSEB issues a Technical Feasibility Report — commonly a few weeks
- Installation by a registered vendor once feasibility is cleared
- Inspection and commissioning by KSEB
- Bi-directional meter installed and net metering activated
- Subsidy credited to your bank account after commissioning
What affects your actual generation
Two roofs of the same size can produce very different amounts. Orientation and tilt matter, but shading matters more than most people expect — a parapet wall, a water tank or a neighbouring coconut palm can cut the output of an entire string, not just the panel it shadows.
Kerala's monsoon also shapes expectations. Annual generation is what determines your payback, and a good installer will project across the year rather than quoting a sunny-day figure. Ask for the annual estimate, and ask what shading assumptions it makes.
Questions to ask before signing
- Is this capacity sized against my actual bills, and can I see the working?
- What annual generation is projected, and what shading is assumed?
- Which subsidy tier does this system fall into?
- Who files the application and handles the KSEB paperwork?
- What is the realistic timeline from application to net meter?
- What does the warranty cover — panels, inverter, and workmanship separately?
The short version
The subsidy reduces your upfront cost and is paid to you after commissioning. Net metering settles your bill on import minus export. Size the system against your real consumption, take shading seriously, and confirm current scheme rates before committing — they are set by policy, not by your installer.