More than 30% a year: the return on a rooftop solar plant

People often ask whether solar is worth it. The honest way to answer is to treat it as an investment and ask two questions: how many years until it pays for itself (the payback period), and what does it return each year after that?

The payback period

Take what the plant costs you after subsidy, and divide it by what it saves you each year. A 3 kW plant in Lucknow makes about 4,500 units a year. At ₹7 a unit that is about ₹31,500 saved every year. After PM Surya Ghar's ₹78,000 and UP's ₹30,000 subsidy, the family's own share is typically paid back in 3 to 4 years.

The yearly return

Divide the yearly saving by what you paid: for most subsidised home plants this comes to 25% to 35% a year, tax-free, because money you do not spend on electricity is not income. Few safe investments come close. And as tariffs rise, the return rises with them.

What makes the return real

The return only holds if the plant keeps working at its best for 25 years. That is why we design every plant on a 3D model of the roof to avoid shade, use quality panels and inverters, and watch every plant every 15 minutes, so a fault or a dirty panel does not quietly eat your savings.