On one side there is a growing interest on large scale solar power projects of MW size in the investors, there are investors who are also focusing on the smaller segment of rooftop solar systems, where you can install solar PV system on your roof and use it for your own purpose and surplus electricity can be sold to the grid. While there is already a capital subsidy of 30% from MNRE for off grid PV systems, the grid connected systems can get a preferential tariff (Feed in Tariff) or the REC9 Renewable Energy Certificates) for sale of their electricity to the grid. Even your self consumption is also considered as the deemed generation for the consideration of feed in tariff.
The rooftop owners having roof top sizes in the range of 30000 -10000 sq. The ideal rooftop should be flat and relatively free of obstructions, and should have good exposure to sun. While there is a regular power cuts to the households, the solar rooftop systems are ideal way to the home owners to go for the rooftop solar PV systems. The major barrier is the high upfront cost. In-order to overcome this, the home owners can explore the feasibility of rooftop solar PV systems on their roof, through the third party installers. A growing number of third-party solar power providers are looking to rent roof surfaces from the home owners and install PV systems and sell the power generated to the home owner/local utility through the different available scheme of solar rooftop policies of government of India. Even commercial building owners can also lease their rooftop on rent to the solar PV developers and can do a long term PPA to use the electricity generated through the PV system.
Germany is the largest installer of rooftop PV systems and the typical sizes of roof top systems are in the range of 10kW -50kW systems. A 50 kW rooftop system typically produce about 250 kWh in a day. The typical lease rentals for rooftops are of the order of about €1.00 / sqm / year. Many solar developer offer a prepayment of full 20 year lease in advance and get the rooftop space on lease at a lower cost.