Establish the utility before anything else
New Mexico is served by more than one investor-owned utility, plus municipal utilities and cooperatives, and their solar terms are not identical.
Because solar savings are the price of the electricity you no longer buy plus what you receive for what you export, both halves of that depend on which utility you are on.
So look at the utility name on a recent bill first, and treat any figure in a quote that was not built from your utility terms as provisional.
The state-level incentives are not affected. The Solar Market Development Tax Credit, the gross receipts tax deduction and the property tax exemption all apply statewide regardless of utility.
What to establish with your utility
Ask how exported generation is compensated, at what rate, and whether that rate is fixed or reset periodically. If it is reset, ask whether existing customers move to the new rate.
Ask whether netting is instantaneous, monthly or annual, and whether excess credits carry forward or expire on a set date. Those two answers determine how the system should be sized more than anything else.
Ask what system size limits apply and whether any threshold changes the export treatment, as the 10 kW AC line does under PNM.
Ask what the interconnection application involves, what it costs, how long approval takes, and whether any solar-specific charge or minimum bill applies.
Strong resource, hot summers
South-eastern New Mexico has excellent sunshine hours, which is the part of the calculation that does not depend on your utility and the reason the state ranks well for solar overall.
Summer heat cuts the other way. Panels lose efficiency as module temperature rises, so a hot climate reduces output relative to the same irradiance in a cooler one.
Ask how the production model handles temperature derating and what module temperature assumptions it used. A model that applies irradiance without temperature correction will overstate a Hobbs roof.
Ask about soiling as well. In a dry, dusty and windy region, accumulated dust is a genuine production loss between rainfall, and a model assuming none is optimistic.
What a projection here needs to contain
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 receives no federal tax credit. Section 48E survives at 30 percent for third-party owners under leases and power purchase agreements.
The state Solar Market Development Tax Credit remains at 10 percent up to $6,000, subject to the $30 million annual cap and the one-year application window, and Senate Bill 55, which would have raised it to 30 percent, did not pass.
Add the gross receipts tax deduction and the property tax exemption, both statewide and both appearing as absences rather than payments.
Then add your own utility export terms and your actual retail rate, and a production estimate that includes temperature derating and soiling. Ask for it in writing with each assumption named.