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Net metering is a tariff, not a battery
By the end: Explain net metering and net billing and identify the rules that must be checked locally.
Net metering describes arrangements that credit eligible customer generation sent to the grid against electricity taken from it. The precise netting interval, eligible charges, rollover, and settlement rules differ. The phrase alone does not establish one-for-one retail credit or a cash payment for every exported kWh.
Net billing commonly values imports and exports separately, potentially at different prices. Time-of-use rates can also make a kWh worth different amounts at different hours. California’s CPUC describes net metering and net billing as distinct programs; that is a jurisdiction-specific example, not a rule for all utilities. Always find the current tariff for the actual utility, customer class, and interconnection date.
The grid is not a personal battery that stores your daytime electrons for return at night. Export supplies the shared electrical system; credits are accounting entries. A favorable annual energy balance can still leave fixed charges, non-offsettable charges, financing costs, or other bills.
- Is the proposed system eligible, and is export permitted?
- What interval is used for netting? What are import prices and export credits?
- Do credits roll over, expire, or settle in cash? Which charges cannot be offset?
- Are there size limits, fees, time-of-use requirements, or later changes that affect this customer?
Quick check
Which fact is NOT established by hearing “net metering is available”?