What is modeled — and what is not
Production
1,217 kWh/kW-year state planning benchmark from the existing PVWatts-based CalcuRiver dataset.
Installed cost
$2.75/W planning benchmark for Vermont.
Electricity value ceiling
23.75¢/kWh · EIA residential benchmark for Vermont (2026-07).
Green Mountain Power rate context
16.33¢/kWh · Rate 74 off-peak. This is utility rate-plan context, not a verified solar export-compensation rate.
Utility source: Green Mountain Power Rate 74 — TOU EV Residential · verified 2026-09-29.
Production: NREL PVWatts methodology · Cost: 2026 state / local marketplace benchmark.
Why exact Green Mountain Power solar savings stay guarded
CalcuRiver has a calculator-ready utility rate profile for Green Mountain Power, but that does not automatically make the same plan a valid solar import/export tariff. Until a solar-specific compensation rule is verified, the calculator shows production, cost and a retail-value ceiling without flattening export compensation to an invented rate.
Continue this Vermont cost analysis
Why this solar estimate changes
Solar value is driven by local production, installed cost, the retail value of electricity you avoid buying, and the compensation you receive for exported energy. CalcuRiver does not assume export credits equal the retail rate unless that utility program is explicitly verified.
Core logic: self-used solar offsets retail purchases; exported solar is valued only under a verified export-compensation rule.
Methodology & source policyConnect solar to the rest of the utility bill
Solar economics are easier to interpret when the tariff, storage and vehicle loads are connected to the same local context.