The retail price is the whole argument
Every kilowatt hour your system produces and your household consumes displaces one you would have bought at the retail price. At around 27.4 cents per kWh that displacement is worth roughly double what it would be in a low-cost state.
This matters for how you read a quote. Incentives are finite and mostly one-off; avoided electricity cost recurs every month for the life of the system, and it is the term that dominates a 20-year or 25-year projection.
It also means a quote leading with incentives and treating avoided cost as an afterthought has the emphasis backwards. Ask what proportion of the projected savings comes from avoided electricity purchases rather than from programmes.
A high retail price is not permanent either. PURA approved an interim decision lowering residential rates from May 1, 2026, including by about 4.3 cents per kWh for an average Eversource residential customer, which is a useful reminder that rates move in both directions.
Supply, delivery, and which one solar offsets
A Connecticut electricity bill separates supply from delivery. The Eversource Standard Service supply rate was 11.58 cents per kWh for July 1 to December 31, 2026, which is well under half the all-in residential average.
The rest is delivery and the various charges that ride on it. Whether a solar system offsets those components, and to what extent, depends on the tariff and on how the charge is structured, which is why the blended number is the one that matters rather than the supply rate alone.
This is a common place for a projection to go wrong in either direction. A model using only the supply rate will badly understate savings; a model applying the full blended rate to every kilowatt hour without checking the tariff mechanics may overstate them.
Ask which rate the projection applied, and whether it used supply, delivery or an all-in blended figure. Then ask where that figure came from and what date it is current as of.
The escalation assumption to interrogate
Most long-run solar projections assume electricity prices rise over the term. That is a reasonable assumption in general and a very powerful one in a projection, because a compounding escalator applied over twenty-five years can generate most of the headline savings on its own.
Ask what annual escalation rate the model used. A modest figure is defensible. A large one deserves scrutiny, particularly given that Connecticut rates fell in 2026 rather than rose.
Ask to see the projection at a lower escalation rate as well, or at zero. If the case still works with no escalation at all, that is a robust case. If it only works at an aggressive rate, you have learned something important about the quote.
The same discipline applies to the Solar Energy Adjustment, which is reset annually and which a projection may be holding flat at the 2026 figure of $0.0402 per kWh for the whole term. Ask which way that assumption cuts.
Costing it out with the adjustment applied
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 Norwalk receives no federal tax credit. Section 48E survives at 30 percent for third-party owners under leases and power purchase agreements.
What exists is the 20-year RRES contract on the Netting or Buy-All tariff, the Solar Energy Adjustment at $0.0402 per kWh of total generation for 2026 Netting enrollees, and the income-eligible adder where the household qualifies.
Add the sales and use tax exemption under CGS Section 12-412 and the property tax exemption under CGS Section 12-81, checking whether your town requires a filing with the assessor.
Then add the electricity you stop buying, priced at a stated and sourced retail figure with a stated escalation assumption. Ask for the version with no escalation as well, because a case that survives it is a case you can rely on.