What a 20-year tariff commitment means
RRES is a 20-year contract between you and Eversource or United Illuminating, and the choice between the Netting and Buy-All tariff is fixed at the start for the whole of it.
Twenty years is longer than most people stay in a house, longer than the finance term on most systems, and long enough that the electricity market will look materially different by the end of it. That is an argument for understanding the mechanics rather than for avoiding the commitment.
Ask what happens to the contract if you sell the property, and get the answer in writing. A tariff attached to a property becomes part of what a buyer is taking on, and it is better understood before you sign than during a sale.
Ask also what the contract says about system changes. Adding capacity, replacing an inverter or adding a battery years later can interact with the tariff terms, and knowing the rules early shapes whether you build in headroom now.
Sizing under a tariff, not under net metering
Old-style retail net metering rewarded building large and letting an annual surplus settle up. RRES does not work that way, and the Solar Energy Adjustment on 2026 Netting enrollees makes oversizing actively costly, because the charge applies to every kilowatt hour generated.
A system producing more than your household can use is generating kilowatt hours that attract the adjustment while earning only export compensation. That is the wrong end of the trade.
So the design should be built from your last twelve months of bills. Ask what percentage of your annual usage the proposed system covers, and ask what specifically justifies any capacity beyond it.
A concrete planned increase in load, such as an electric vehicle or a heat pump, is a sound reason to size ahead. A general sense that more is better is not, and under a 20-year tariff with a generation-based charge it is expensive.
The storage commitment is its own decision
Energy Storage Solutions performance pay runs on a 10-year term, so a battery enrolled in the programme carries a decade-long relationship of its own alongside the 20-year solar tariff.
Since April 1, 2026 the enrollment incentive has been $30 per kWh for most customers, with a $130 per kW Grid Edge adder on constrained circuits, and performance pay at $300, $450 or $550 per average kW discharged during peak events depending on your category.
Because most of the value now sits in the performance stream rather than upfront, the assumptions behind the projected dispatch matter. Ask what average kW the model assumes and where that number came from.
And weigh the two terms together. A household expecting to move within a few years is making a different calculation from one settling in for twenty, and that should shape both the tariff choice and whether storage is enrolled at all.
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 Danbury 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 is at or below 60 percent of State Median Income.
Energy Storage Solutions adds $30 per kWh at enrollment plus a 10-year performance stream, and the sales and property tax exemptions under CGS Sections 12-412 and 12-81 both apply.
Add the electricity you stop buying at roughly 27.4 cents per kWh, and insist the system is sized from your last twelve months of bills rather than from your roof. Under a generation-based charge, an oversized system costs you twice.