How it works

Electric customers that generate their own electricity from a solar photovoltaic (PV) or other renewable energy source are eligible to participate in a billing arrangement called net metering. If the generation facility is a solar PV system, first the DC electrical energy produced must be converted to AC through an inverter before fed into the utility network. The power generated in excess of the owner’s electricity consumption is fed into the grid through a bi-directional energy meter capable of registering both import and export of electricity. The arrangement of a net metering system utilizes the same service line for excess power injection into the grid which is already being used by the consumer for draw of power from utility network. However, an electrical inspection is normally carried out prior to energizing a generation interconnection to verify whether the generation arrangement meets utility, product safety and grid interconnection specifications and standards.

Net-Metering allows households to generate electricity and set off the power produced against the power used from the national grid and consumer pays only for the “net” number of units (difference between import and export energy) used each month. In the event the consumer produces power in excess of his usage in a particular month, the customer’s energy charge becomes zero and the remaining number of units will be credited and carried forward to the following month. Normally most of electricity companies allow carrying forward the excess electricity generated for up to one year period. Some electric companies (Not in Sri Lanka) may pay back to the consumer for the extra power if more energy has been injected into the system than the consumer has used.