Understanding Net Metering for Home Solar (Credits, Exports, and Bills)
How grid-tied billing treats exported kWh, import charges, and why NEM policy changes your payback.
Net metering is the contract between your roof and the utility. It defines how exported solar energy is valued against what you draw at night. Policy names differ by state, but the mechanics rhyme.
Self-consumption is the best kWh
When panels power loads in real time, you avoid buying retail power—full value in most regions. Export happens when production exceeds use. Credits may match retail rate (true net metering) or a lower export tariff (net billing).
Reading a post-solar bill
You will still see fixed customer charges. Energy charges split into kWh imported minus credited exports depending on tariff. Time-of-use plans reward west-facing bias if evening rates spike.
Policy shifts matter for new projects
Utilities increasingly move toward lower export credits while keeping retail import rates. A system sized for one hundred twenty percent of last year's use under old NEM may look different under export-heavy tariffs. Model both.
Oversizing and undersizing
Oversizing production without load can export cheap electrons. Undersizing leaves billable imports. Target net-zero on an annual kWh basis as a first pass, then refine for rate structure.
Grid-tie solar is a partnership with the meter. Understand how your utility values exports before you sign interconnection—and simulate monthly import/export, not just annual totals.