The rate you sign up on is not the rate you keep
The Schedule 137 export credit rate is recalculated annually and takes effect each March 1. That in itself is common enough; what is unusual is that the new rate applies to existing customers, not only to new applicants.
In most states a solar customer is grandfathered onto the terms in force when they interconnected, often for ten, fifteen or twenty years. Utah net billing customers are not.
So a 25-year savings projection built on the current export credit is assuming twenty-five annual recalculations will leave the figure roughly where it is. That is an assumption rather than a term of the tariff.
The direction so far has been downward. Summer export credits have moved from about 5.817 cents per kWh in 2020 to 5.160 in 2022 and roughly 4.855 by 2026, with winter rates falling further in proportional terms.
How to price that uncertainty
The right response is not to avoid solar over it, since the retail-rate portion of your savings is unaffected by the export credit. It is to make sure the projection separates the two.
Ask what proportion of the projected savings comes from exports at the export credit rate rather than from electricity you consume yourself. That proportion is the part of the case exposed to annual recalculation.
Ask for the projection with the export credit reduced, by a quarter and by half, so you can see how much of the case depends on a rate nobody has promised you.
A design whose value sits mostly in self-consumption is largely insulated from this. A design whose value depends on exporting a lot is not, which is another argument for sizing to your household rather than to your roof.
The two ways to reduce your exposure
The first is sizing. A system matched to what your household actually uses during daylight exports less, so less of its value rides on a rate that resets each March.
The second is shifting consumption into the generating window. Dishwasher, laundry and electric vehicle charging moved into daylight all convert export-rate kilowatt hours into retail-rate ones, and they cost nothing.
A battery does this at a larger scale, and in a net billing state that is a genuine economic argument rather than only a resilience one. Ask for the system modelled with and without storage so the incremental value is visible.
Note that the retail rate is itself moving, and generally upward. That works in your favour on the self-consumption side of the ledger, which is another reason to weight the design toward it.
Rebuilding the estimate from current figures
The 30 percent federal Residential Clean Energy Credit under Section 25D expired for property placed in service after December 31, 2025, and the Utah residential solar tax credit reached zero for systems installed from 2024 onward, so a cash or loan purchase receives no tax credit at either level.
Section 48E survives at 30 percent for third-party owners under leases and power purchase agreements, so ask what a provider claims and what reaches you in the rate.
What exists is retail value for self-consumed generation and a seasonal export credit that is reset every March for existing customers as well as new ones.
Ask for the projection with those separated, and with the export credit stress-tested downward. The part of your return that depends on it is the part nobody has guaranteed.