While the whole world – and India – is focussing on solar PV, the other solar counterpart, solar thermal, has enormous potential as a renewable energy source.
Solar thermal sources can be used for both heating and power production. Among these two, its use for heating and drying purposes has much higher potential in the short and medium term.
This article provides a detailed analysis of solar water heaters in the Indian context.
Solar water heaters are not exactly new in India. Every year, over 20,000 solar water heaters are installed across India, according to some estimates.
Some of the salient points about solar water heating in India
1. The payback period is less than 4 years.
2. Typically, for an Indian make system with single BIS approved flat plate collector of 2 sq. m area (required for an average household), the current market costs are reported to be in the range of Rs. 15,000-20,000
3. Based on the price of electricity and the region in India where it is installed, the savings per year for a typical Indian household through the use of solar water is in the range of Rs. 4000-7000
4. Solar water heaters last 15-20 years. This implies that beyond the breakeven period of 4 years, you get hot water at no cost at all.
5. IREDA (Indian Renewable Energy Development Agency) provides soft loans at 2% to domestic users, 3% to institutional users not availing accelerated depreciation and 5% to industrial/commercial users availing depreciation. The government also provides an interest subsidy, besides a 5% rebate on property tax. Capital subsidy is available for installation of solar water heating systems to registered institutions and commercial establishments.
In spite of these obvious benefits and incentives, the penetration of solar water heaters in India is much less than desirable. Consider this: China now has 27 million households equipped with solar water heaters! The country has a solar water heater production of about 4,000 manufacturers, and the existing solar water heaters convert solar energy to the equivalent of the capacity of 49 coal-fired power plants.
India is far, far behind China in solar water heaters. But there are some bright spots:
1. The State of Karnataka has done a commendable job in solar water heating. Bangalore has the largest deployment of rooftop solar water heaters in the country, generating a daily equivalent of 200 MW, with 60% of the city’s household and industrial units using solar water heaters. The Government of Karnataka (through the Karnataka Renewable Energy Development Limited–KREDL) has made roof-top thermal systems mandatory for all new residential/industrial structures and has implemented a Rs 50 (about $1.10) discount (subsidy) for the monthly electric bill from the Bangalore Electric Supply Company. Wish the other cities in India are as renewable energy friendly as Karnataka.
2. It seems Pune is also going the solar thermal way. The city not only is home to majority of the solar equipment manufacturers in the state but also has made installation of solar water heaters in new buildings mandatory. Currently, about 20 per cent of the houses in Pune are using solar water heating units. This percentage would increase because of the central government incentives, according to industry watchers.
3. I was in Delhi recently, and was travelling by road from Delhi to Gurgaon. I was pleased to see a number of apartment complexes with solar water heaters. Not sure if it was mandatory, but it was good to see them all the same.
I think the solar water heater industry in India could grow at exceptional pace from now on, given the increasing green consciousness among the public, the increased promotion campaigns from the manufacturers of water heaters and the government incentives.
Let’s hope my prediction comes true!
You might be interested in reading this post as well – Solar Water Heaters is a 120 Crore Market in India