Tata Powers cool solution: Solar panels on rooftops

Written by Subhash Narayan | New Delhi | Updated: Jun 11 2014, 06:20am hrs
Delhi has a savior in Tata Power. The company's arm, Tata Power Delhi Distribution, plans to launch a unique rooftop solar initiative that will allow residents of north Delhi to produce solar power and even sell it to the discom at a profit if they have a surplus or do not wish to use it.

The plan, which would be voluntary, involves setting up of small capacity solar (photovoltaic) panels on rooftops. Starting with 1 kw, such installations can go up to a few megawatts.

These would then be converted into power stations that are permitted two-way flow of electricity (between consumers and discoms and back) with the use of micro controllers.

This is a unique initiative that we are planning to launch sometime next year after completion of a US Trade and Development Agency (USTDA) funded study. The idea is to create 200 mw of this capacity in three to four years time, said TPDDL CEO and executive director Praveer Sinha.

He said that the company would facilitate the entire process by tying up with solar PV vendors and also approach the Delhi Electricity Regulatory Commission (DERC) to fix tariff for power produced from these consumer driven solar panels.

The company is also looking at some subsidy from the state government for consumers interested in participating in the scheme. The Centre currently provides 30% capital subsidy for solar installations and also investors get accelerated depreciation benefits.

A 1 kw of solar PV installation roughly costs between Rs 70,000 to 80,000 and generates 4 to 5 units a day. Such installations take up roof space of about 10 to 12 square metres. If TPDDL plans to produce 200 mw of solar power under this route, it will have to get close to 2 lakh consumers on board for the 1 kw PV panels. The numbers could be lower on bigger capacity solar PV panels.

Sinha said that all rooftop PV systems could have a single bi-directional meter to measure the import and export of electricity. Consumers could be charged on the net consumption of at the end of the billing cycle. In case a consumer is a net generator and exporter, he/she can be paid for such supplies at tariff determined by the regulator. The regulator could either have separate tariff for solar power generated by domestic and commercial consumers or could evolve a pooling tariff mechanism.

...rooftop solar could be a stop gap solution in the short term, said Ratul Puri, chairman, Hindustan Power Projects formerly known as Moser Baer Projects.

"I feel all the state governments should notify 5 to 10% renewable energy generation by home and commercial consumers in a policy, said Sridhar Raghavendra, energy expert, Girem. Girem is a collective body working with local governments in the areas of infrastructure planning, growth and development.