What the siting adjustor does
Vermont net metering compensation is a blended residential rate modified by two adjustors. One is the REC adjustor; the other is the siting adjustor.
The siting adjustor reflects the Commission preference for systems placed on sites it considers preferred, which is a policy lever aimed at where solar gets built rather than at how much of it gets built.
For a rooftop residential system the practical question is narrow: which category does your installation fall into, and what adjustor value attaches to it.
That is a specific number, and like the blended residential rate and the REC adjustor it can be checked rather than accepted.
Making it visible in the quote
Ask which siting category your installation falls into and what adjustor value applies, stated separately in the projection rather than absorbed into a compensation rate.
Ask how that category was determined and whether anything about the design affects it. If a design choice changes the category, that is worth knowing before the design is fixed.
Ask whether the adjustor value in the projection reflects the tariffs effective August 1, 2026 or an earlier filing, since the Commission has been revising these values through the biennial process.
Then add the three components yourself and check the total against the compensation rate used. If they do not reconcile, ask why before going further.
The roof questions that come first anyway
Before any of the tariff mechanics, the physical questions decide whether a system is worth building. Ask for the annual production estimate in kilowatt hours per year with the data source named and location-specific irradiance for your address.
Ask what shading analysis was done and what it assumed about tree growth over the system life. Vermont lots are frequently wooded and canopy modelled at today height will overstate output in ten years.
Ask what snow allowance the model applied. Vermont winters bring real snow cover, and its effect depends on panel tilt, orientation and how readily the array sheds.
Ask about tilt specifically. A steeper tilt sheds snow better and shifts production toward the shoulder seasons, which in a northern climate is often a better trade than maximising a summer peak.
What belongs in a Vermont projection
The 30 percent federal Residential Clean Energy Credit under Section 25D expired for property placed in service after December 31, 2025, so a cash or loan purchase in Essex receives no federal tax credit.
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 compensation built from a blended residential rate, a REC adjustor and a siting adjustor, each of which should appear separately in the projection.
Ask for all three stated with the tariff date, alongside a production estimate that accounts for shading, tree growth and snow.