Payback on a 5 kW home system: the numbers

The question behind every enquiry is simple: how long until the system pays for itself? Here is a worked example for a 5 kW on-grid system on a house in Malviya Nagar, using typical figures from this year. Your survey will give exact numbers for your home.

Cost first. A 5 kW system with panels, inverter, galvanised structure, cabling, earthing, net meter and installation costs about ₹2,90,000 in Jaipur at present. Homes with their own connection are usually eligible for the central rooftop subsidy, which for this size was ₹78,000 at the time of writing and is credited to your bank account after the system is inspected. That brings the cost to about ₹2,12,000.

Generation next. In Jaipur a 5 kW system averages about 20 units a day, or roughly 7,000 units a year. If your family uses about 600 units a month, most of that will now come from your roof. Then savings. At an average of ₹7.50 a unit across slabs, 7,000 units saves about ₹52,500 a year. Fixed charges remain, so your bill will not fall to zero. Panel output also declines slowly, by roughly half a per cent a year.

That gives a payback of about four years. After that, the system keeps producing for another 20 years or more, with the inverter likely to need replacing once, at around ₹35,000 to ₹50,000. Cleaning and a yearly check add a small cost. Our care plan is listed separately so you can include it in your sums.