Net metering

Net metering is a utility policy incentive that lets a customer offset on-site electricity use with their own renewable generation, such as a PV system. Any solar energy the site does not use flows into the utility grid, and the owner gets a credit for it on the monthly bill. The utility meter records both the energy taken from the grid and the energy fed into it, and the customer pays only for the net energy consumed. On an Eversource net meter, register ID 04 shows the energy the utility delivered and ID 10 shows the excess generation the utility received. The generator must never be connected inside the meter socket or the instrument transformer compartment. The most common approach gives full one-to-one credit for each kilowatt-hour. Monthly surplus credits carry forward, and an annual true-up compares total consumption with total generation. At true-up, depending on the utility, leftover excess may be paid at the utility's avoided cost, lost, or carried into the next year. Policies vary widely, so get the local utility's net-metering policy before sizing a system. Net metering only covers offsetting on-site loads, so net-metered systems at sites with small loads tend to be moderate in size. Variants include remote, virtual, neighborhood and agricultural net metering. California Rule 21 separates NEM-1 and NEM-2 requests from the newer Net Billing Tariff.

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• sentence 8: support check: partial - Remote, virtual, neighborhood and agricultural net metering and NEM-1/NEM-2 appear, and NBT is defined, but the passages do not say Rule 21 separates NEM requests from the Net Billing Tariff. -->