The recent cost reductions in solar PV has motivated many end users to use on-site or off site photovoltaic (PV) generation to hedge against volatile electric utility bills. In case of onsite generation the end user have an option of installing themself and own the PV system. The another option to the end users is to do a PPA with the third party for long terms and avoid the high capital investments. THe third party PPAs can be done for an on site PV generation as well as for an off site PV generation.
Typically in case of rooftop PV systems the third party signs a PPA with the building owner and sell the solar electricity as a part of onsite generation to displace his costly DG based power generation. As long as this system is completly off grid, there is no problem in terms of meeting the regulatory compliances, however in case of grid interactive systems, if the solar PV installer at a building installs the PV plant, and go for net metering, there are no guidelines from Government of India for net metering of solar electricity. Also it is not clear that the PPA signed by the third party who sells is solar electricity t the building owner as well as to the grid in the event of non captive requirements, is he legaly allowed to sell the electricity to both parties. The third party sale can be done under the group captive mode where the buyer should have stake in a solar spv at least 26% and should at least 51% of solar electricity. Rest of electricity can be sold to the grid.