Net metering allows the consumers who generate some or all of their own electricity to use that electricity anytime, instead of when it is generated. Monthly net metering allows consumers to use solar power generated during the day at night or later in the month. Annual net metering rolls over a net kilowatt credit to the following month, allowing solar power that was generated in July to be used over the next one year.
The electricity bill is calculated on the net units consumed from the grid for the billing period.
Net Units = Imported Units – Exported Units
The net metering policy in India varies from State to State. Each state has its own regulator and rules governing the net metering policy that includes but not limited to subsidy, capacity of installation, component specifications and makes, system installers/ integrators etc. You can visit http://www.ireeed.gov.in/statepolicy# to get more details about the net metering policy in your state