Let’s assume you consume about 10 units (kWh) of electricity daily and have installed a 1 kW solar system on your roof. The cost of a 1 kW system in 2015 is approximately INR 1 lakh (without any government subsidy). The lifetime of a typical solar system is 25 years. So, in simple terms, the system would cost you INR 4,000 per year.
A 1 kW system would provide you roughly 5 units of electricity per day. These are 5 units of power you don’t have to buy from the grid. At a grid power price of INR 3 per unit of electricity your bill would reduce by would save around INR 5,500 a year. This not only covers the cost of the solar system but also saves you another INR 1,500 a year!
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