Gross metering systems are aimed at rooftop owners/third party investors who will like to sell energy to the DISCOM by using roofs owned by them or another party. It is also known as feed-in metering wherein, all the energy generated from the system is exported to the grid and is separately recorded through a different ‘feed-in meter’. The developer exports the solar energy to the utility at a predetermined feed-in-tariff (FiT) approved by the regulator, and the third-party investors/RESCO developers enter into a long-term Power Purchase Agreement (PPA) with the utility.
Only grid-connected PV systems can be gross-metered.
Net metering systems are primarily aimed at providing an opportunity to consumers to offset their electricity bills, wherein a single meter records both import of conventional energy from distribution grid and export of solar energy into distribution grid. Thus, net metering allows the final user to credit produced energy in the grid and is also promoted as a preferred option.