The country is gearing up for a solar revolution as the Prime Minister has recently raised the target of solar electricity generation, from 20,000MW to 1,00,000MW, to be achieved by 2022. Set at a cost of $100 billion, this ambitious project aims at encouraging individuals and companies to switch over to renewable energy sources. While many home owners have now understood the benefits of solar technology, and have installed solar panel-based systems in their homes, experts say that unless the government doesn’t encourage the commercial sector and developers in particular, individual efforts don’t really serve the purpose.
Relevance in commercial projects
Renewable energy sources such as solar are cheap. With their decreasing costs, they cost cheaper than the grid for many industrial sectors, says Narasimhan Santhanam, co-founder and director, Solar Mango. An initiative by Energy Alternatives India (EAI), many of the solar consulting firm’s projects involve installing rooftop solar power systems for industrial or commercial sectors, or assisting in the setting-up of large solar farms. M.B. Nirmal, founder, Exnora International, says that while the government offers attractive subsidies to home owners, the environmental costs are not taken into account. “Big companies and developers need to be encouraged to adopt renewable energy sources. For instance, switching to solar should be counted in the CSR activities of companies. Developers should be incentivised to power the common areas in their projects with solar energy,” he says. In his recent visit to the Green Building Congress, developers agreed to install solar panels in their projects, if given permission to construct an additional floor or two. Dr. R Kumar, managing director, Navin Housing and Properties, who has installed solar water heaters in each of the villas of his project at Karapakkam, says, “Although developers need to encourage sustainable development, we also need to consider it’s practicality and economic viability.
The cost of installation and maintenance of solar panels seemingly overweighs the benefits.” A concerted effort by the government is needed to encourage end-users to shift.
The cost factor
A recent JLL report points out that even though the upfront cost of installing a solar system is on the higher side, it pays off in the long run. Ashwinder Raj Singh, CEO, Residential Services, JLL India, says a rooftop solar system will cost approximately Rs. 1 lakh per KW (excluding the cost of incentives and batteries). “It has a life of 25 years and will deliver 90 per cent efficiency in the first 10 years of installation, and about 80 per cent from years 11-25. Batteries account for almost 30 per cent to the cost of the total system,” he says in the report. To generate 2000 watts of electricity, one would need around 200 sq. ft. of space on the terrace. It is not recommended for anyone to be fully dependent on solar power alone, especially the industrial or commercial sectors. Solar panels on rooftops can only partially substitute the grid for these sectors. Santhanam says, “For select household segments, rooftop panels might be able to contribute most of the power requirements if they are willing to install reasonable amounts of battery backup systems.”
Before making the switch, a buyer has to analyse his/her energy requirements, based on the electrical equipment used. A solar system is good enough for major electrical appliances except for water heaters and air conditioners, for which separate, higher-capacity solar panels are available. A solar panel works best on a flat terrace, rather than on slanting surfaces.
Maintenance and installation
Santhanam says solar power plants — rooftop ones or large farms — require little maintenance other than the occasional cleaning. If it is a battery-supported panel, a bit more maintenance is needed, but not very significant.
The other components of the system such as the inverter, wires and so on, should be of good quality, as lower quality components will wear out faster, and add to the maintenance cost. “For inverters, the best option is a pure sine wave model. This is slightly more expensive, but efficient and long-lasting,” says Singh.
Apartments can use solar plants to supplement grid power during electricity outages, which are common across the city. Chandan Jain, managing director, Vijay Shanthi Builders, says, “Solar power can easily replace noisy and polluting diesel generators, and the cost of installation can be recovered within 5-6 years.”
Subsidies
Since the cost of batteries is prohibitive, various State Governments and electricity boards are offering subsidies along with special deals.
Any surplus power that a residential solar panel generates can be sold back to the government-operated grid at good prices. “At the end of the month, if the net outage of power towards the grid is more than inflow, the society or individual home owner stand to make a profit,” says Singh. As per the TN Government rules, individual applications for 1 kWp plants (for residential purposes) will be considered for a government subsidy of Rs. 20,000 per kWp. Chandan says that the subsidy can be availed only by domestic consumers with a TANGEDCO service connection.
Solar power that is not consumed can be exported to the grid, and will be eligible for solar net-metering.
