In my journey to go solar, I realized that people who are willing to go solar have to go through the hassle of figuring out a lot of formalities. I am writing this article detailing the basics of an on-grid solar plant and how you can go about getting your rooftop solar like I did :
Determining capacity as per your requirements — The best way to check this is by analysing your consumption history over the year. Do this either by keeping a track or logging onto your discom's website. In case of TATA power, their consumer portal keeps a record of around 2 years of consumption. I had a peak consumption of around 1200-1300 units during summers and around 250-300 units in winters. To figure out the size of solar array you need, you should check the average units you consume over the year. In Delhi, is it quite sunny for around 7 months of the year which led to my average consumption of 785 units for past one year.
Also, on an average 1kW solar array generates on an average 4-5 units a day. Obviously, there are variations if there is inclement weather or outright sunny. Here's a graph showing monthly units generated from a 5kW solar plant:
The average generation over the year turns out to be 616 units. Different discoms have different policies on how they reimburse you if you generate more units that you consume. However, it is better to go for a system which is around 80% of your sanctioned load and meets the same proportion of your average demand.
Subsidies — Subsidies are determined by Ministry of New & Renewable Energy (MNRE) and state governments. Subsidies are given over the benchmarks costs set by MNRE - these benchmark costs vary by state. Please note, these benchmark costs include installation charges, fees, taxes etc. A quick search on google will land you on MNRE's latest circular or notification. For instance, benchmark costs for year 2019-2020 are as follows (Source: MNRE)
Before subsidy, a 5kW plant will cost INR 2.70Lakh (54 * 1000 * 5). Government as per its various phases of its plans rolls our subsidy to increase the uptake of solar by consumers. The latest notification of MNRE's website outlines the subsidies provided by them:
In Delhi, there is an upfront subsidy of 30% provided by IPGCL on a first come first serve basis. Under this, the consumer needs to pay the subsidized amount instead of getting subsidy after the installation. Any state wise policy supersedes the subsidy provided by MNRE as state nodal agencies issues tenders for vendors to get themselves empanelled. For more details on subsidy by state please refer to this website.
I got my rooftop solar from Zunroof which took care of getting all the subsidies since it was empanelled with IPGCL. The company is currently offering a flat rate of INR 29,400 per kW. Here's a breakup of the quote offered to me for a 5kW plant by the company:
However, the installation came with its own challenges which I have detailed below:
Given this was my first project, I was not aware of the potential delays during delivery of panels or its installation. I confirmed my order on 3rd June 2019, paid the amount in full by 12th July 2019. The panels were delivered around a month later and no work had started either by then. After repeated calls and follow-ups, the installation started with its own set of delays and challenges. If everything was done efficiently, setting up the plant and commissioning it can be done in a week. I raised a formal complaint against the company which expedited the installation. After discussions with the company, they have promised to mention the commissioning date in order confirmation contract.
Post sales service - After 15 days of commissioning, I noticed a sudden drop in units generated because of frequent power graphs. After ensuring that there were no intermittent power cuts, I realized that inverter was cutting off the power because of excess voltage (250 volts as opposed to 220-230volts) by the grid. I raised a complaint with Zunroof to which they quickly responded by sending an engineer to fix this. However, to my dismay the engineer did not provide an apt solution and blamed it on my Tata Power. I raised a complaint with Tata Power who then checked the voltage and stated that a higher voltage is "normal". Unhappy with the responses I got, I made an attempt to contact the inverter manufacturer who guided me to change the country setting which fixed the problem.
Even after all these delays and issues, I would like to emphasize that going solar is the best decision I have made. Zunroof has helped me in realizing my dream of power independence.
The performance of the panels is in line with expectations. So far, the plant has generated more than 435 units. At this rate, the expected payback period is around 2-3 years.
Go Solar! Act on Climate! Save the Earth!