California Net Billing Tariff (NEM 3.0)

The California Net Billing Tariff, also called NEM 3.0, covers metering of electricity received from and delivered to a customer generator by the distribution provider. Rule 21 sets the interconnection, operating and metering requirements for generators connecting to utility distribution systems under CPUC jurisdiction. If a homeowner adds PV to an existing NEM 1.0 or NEM 2.0 system, California requires the whole site to move to NEM 3.0 under Rule 21. That change of tariff alters the solar credit the existing system earns, and it can leave the customer worse off depending on the size and type of the expansion. Enphase describes NEM-MT CT wiring as a California option for expanding net metering systems without changing the tariff of the existing system.

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• sentence 1: support check: partial - u5 defines NBT as metering for receipt and delivery of electricity between Producer and Distribution Provider, but the passages don't explicitly equate NBT with NEM 3.0 (u1 uses NEM 3.0 without the link) and say 'Producer' rather than 'customer generator'.
• sentence 3: support check: partial - u1 says homeowners must move from existing tariffs to NEM 3.0 when adding PV, but it doesn't say 'the whole site' explicitly, though the existing system's credit is affected.
• sentence 1: review: partial - Rule 21 defines NBT as metering for receipt and delivery of electricity between Producer and Distribution Provider, but neither passage says NBT is also called NEM 3.0. -->