Net Metering: How Export Credits Change Payback
Two homes with identical panels and identical sun can land years apart on payback, and the difference is usually not the hardware — it is what the utility pays for the solar these homes push back onto the grid. This page explains the three tariff types and puts a dollar figure on the gap.
Planning estimate only - not tax, legal or financial advice. Confirm installed cost and current incentives with a licensed installer and the official IRS and Energy.gov sources.
Full retail — the strong case
- Every exported kilowatt-hour cancels a purchased one at the meter price.
- Your panels offset the most expensive electricity you buy, so each one carries full value.
- Typical of several states on the state table; payback runs shortest here.
- No battery needed to make the math work — the grid acts as free storage.
Weakened — the honest hard case
- Exports are paid near wholesale, a fraction of the retail price.
- California’s NEM 3.0, in effect since April 2023, is the model: new systems earn little for exports.
- Self-consumption becomes the whole game — use your own power, or store it in a battery.
- Payback stretches unless daytime usage is high; batteries help but add cost.
Solar cost versus grid electricity
A solar system is a one-time price for a machine that makes electricity for decades; the grid is a never-ending bill per kilowatt-hour that historically trends upward. Comparing them is about levelized cost: spread the net system cost over its lifetime production and you get a price per kilowatt-hour you can set against your utility’s rate. When that number sits below your rate, every year of operation saves real money — and the export tariff decides how much of your production actually counts. A weak export credit does not change what your panels produce; it changes how much of that production the bill acknowledges.
This is also why export policy is where solar decisions are won or lost today. Hardware prices are broadly similar everywhere, and the federal credit no longer differentiates — but tariffs vary enormously by state and utility. Before signing anything, read your utility’s solar tariff sheet and find the export line. If it says full retail, the strong case applies. If it says something close to wholesale, size the system to your daytime usage and price the battery honestly.
Net metering questions
What is the difference between full retail and wholesale export credit?
Full retail means every exported kWh cancels a purchased kWh one-for-one at the meter price. A wholesale or capacity-style tariff pays only a slice of that. Same panels, same sun, but the value of what you export can drop by half or more between the two treatments.
Why did California cut its export credit?
California’s NEM 3.0, in effect since April 2023, pays new systems close to wholesale rates instead of the retail price. The state’s goal was to push solar paired with batteries and daytime self-consumption. The practical result: payback there now depends far more on using your own power than on exporting it.
Does net metering change payback that much?
It is the biggest policy lever after the system price. The comparison calculator above puts a number on it: for a typical home system the yearly gap between a full retail tariff and a wholesale-style tariff is often larger than the entire state incentive most states offer.