The solar water heater system uses the sunlight by the collector installed on the roof and converts the sunlight into heat. It passed the heat by the circulating pump to the water tank. When the collector is hotter than the water in the tank, it is controlled by the thermal regulator. It prevents the circulating pump for overheating. The collector work efficiently in midday during summers as well in other seasons also. In the condition of insufficient sunlight the back up system starts to bring the water to the required temperature. The solar water heater system can produce hot water at a required temperature throughout the year.

What is a Solar Rooftop Power Plant?
In a Solar Rooftop Power Plant, solar panels are installed on the roofs of any residential, commercial industrial or institutional buildings.

How much area is required to install a Solar Rooftop Power Plant?
Typically, 1 kW Solar Plant requires shadow free rooftop area of minimum 10 sq. Mt. Therefore to install a plant of size 30 kW you need at least 300 sq.mt.

How much does a Solar Rooftop Power Plant Cost?
The cost of a rooftop solar PV system depends on the function it serves (to feed power into the grid,to support the load during a power failure, etc.) And incentives subsidies available. Cost also depends upon the type of system viz Grid Connected or off-Grid Power Plant as well as the size of the system. 1 kw Grid Connected system will cost around Rs. 90,000/- to Rs. 100,000/- As the size of system increases, cost tend to come down. The above prices are for components from Tier 1 manufacturers with 5-year manufacturer’s warranty. In addition the PV modules have output warranty of 90% of rated capacity for the first 10 years and 80% of rated capacity for the next 15 years. Cost of battery backup has not been considered as that can alter the economics significantly depending on the extent of backup (autonomy) required. Not only do batteries add to the initial cost but also recurring maintenance, and replacement expenditure as well as the energy loss on charging and drawing from the battery also adds to the cost of power. A battery backup could add significant costs to the above system.