Total Energy Value Returned
RI · REG · 15 YRS
$29,725–$37,975
That's 25–32% of the $117,000 Core40 purchase price returned through energy economics alone.
Cumulative income over time
Upfront
+ Solar income
+ CS low
+ CS high
Upfront incentives
$1,600
One-time at install
RI Energy heat pump rebate + HPWH rebate
= $1,600
Solar income
$1,083/yr
$16,250 over 15 yrs
Annual kWh × Program rate $/kWh
= 3,979 × $0.2723 = $1,083/yr
× min(Years, Term cap) = $16,245 over 15 yrs
ConnectedSolutions
$825–$1,375/yr
$12,375–$20,625 over 15 yrs
Batteries × $/battery/yr (low–high)
= 2 × $413–$688 = $825–$1,375/yr
× Years = $12,375–$20,625
Monthly equivalent
$159–$205/mo
Annualized · REG monthly · CS seasonal
(Annual solar + Annual CS) ÷ 12
= ($1,083 + $825–$1,375) ÷ 12
= $159–$205/mo
Portfolio mode
Annual solar
$108,300
Annual battery
$82,500–
$137,500
$137,500
15-yr total
$2.86M–
$3.69M
$3.69M
Salary equivalent
3.8–4.9
FT salaries / yr
FT salaries / yr
Your 100-unit portfolio generates the equivalent of 3.8–4.9 full-time salaries in passive energy income per year (benchmarked at $50,000/salary).
Assumptions & Seed Values +
Hardware (Core40 standard configuration)
Solar array polycrystalline rooftop, fixed
3.28 kW
Inverter limits ConnectedSolutions ceiling
6,000 W
Battery (Alpha 5 Pro LiFePO₄) 2 units = 10.24 kWh standard
5.12 kWh / unit
Heat pump & HPWH included; trigger upfront rebates
Standard
Core40 retail price denominator for the % returned figure
$117,000
Annual solar production (estimated, seed values)
Rhode Island 3.28 kW × ~1,213 kWh/kW/yr
3,979 kWh/yr
Connecticut 3.28 kW × ~1,175 kWh/kW/yr
3,854 kWh/yr
Massachusetts 3.28 kW × ~1,175 kWh/kW/yr
3,854 kWh/yr
Estimate. Production figures are seeded from regional irradiance averages for an unshaded south-facing rooftop. Actual production varies with site orientation, tilt, shading, weather, and array degradation (~0.5%/yr typical). Site-specific production should be modeled with PVWatts or a comparable tool before contracting.
Solar program rates (locked at enrollment)
RI · REG 15-year term · monthly payment
$0.2723 / kWh
RI · REF + net metering solar income shown as $0 in this calculator
N/A
CT · RRES net rate $0.3289 gross − $0.0402 SEA = $0.2887 · 20 yrs
$0.2887 / kWh
MA · SMART 3.0 20-year term
$0.0300 / kWh
Upfront incentives (seed values)
RI REG $1,600 RI Energy heat pump + HPWH rebates
$1,600
RI REF $2,132 REF solar grant + $2,000 REF battery + $1,600 RI Energy
$5,732
CT CT ESS battery rebate · $250/kWh × 10.24 kWh
$2,560
MA MA state income tax credit (Schedule SC) capped at $1,000
$1,000
Federal Section 25D expired Dec 31, 2025
$0
Unverified. The $2,000 REF battery adder may stack with the REG path — not yet confirmed by RI Commerce or RI Energy. Until confirmed, the calculator does not include this stacking benefit. CT ESS rebate structure changed April 1, 2026; verify current terms at energystoragect.com before relying on the $2,560 figure.
ConnectedSolutions (seed values · scales linearly with battery count)
RI rate $225/kW summer + $50/kW winter
$225 / kW
CT rate
$225 / kW
MA · Eversource
$275 / kW
MA · National Grid
$225 / kW
MA · Unitil does not participate
$0
RI/CT income per Alpha 5 Pro battery scales linearly per slider
$413 – $688 / yr
MA Eversource per battery
$504 – $840 / yr
Performance term · RI & MA contractually locked
5 years
Performance term · CT
10 years
Assumption. When the timeline slider exceeds the contractual performance term, the calculator extrapolates ConnectedSolutions income at the current rate for the remaining years. This is a forecast assumption, not a guarantee — utilities may revise rates or program terms when contracts expire. Timeline ≤ performance term is the most defensible income figure.
Methodology & benchmarks
Battery income range low / high seasonal performance bracket
±25% midpoint
Cumulative chart year-by-year stacking, no time-value discounting
Nominal $
Inflation / rate escalation
Not modeled
Array degradation
Not modeled
O&M, insurance, replacement
Not modeled
Salary benchmark portfolio mode narrative only
$50,000 / yr
Scope. This calculator models gross incentive and program income only. It does not model bill savings, time-of-use arbitrage, equipment replacement at end of useful life, financing costs, taxes on income, or property/sales tax treatment of the renewable equipment. Treat outputs as a directional estimate of program-side income, not a full financial pro forma.
Notes & disclaimers
- Income figures are estimates based on 2026 program rates. Verify program availability and enrollment status at time of purchase.
- REG pays monthly. ConnectedSolutions pays seasonally (post-summer/winter). The monthly figure shown is an annualized average across both programs.
- Rhode Island REF and REG programs are mutually exclusive — you must choose one path.
- CT ESS battery rebate: program structure changed April 1, 2026. Verify current terms at energystoragect.com.
- Federal residential solar tax credit (Section 25D) expired December 31, 2025 — $0 for homeowner cash or loan purchases.
Assumptions & seed values ›
All output values are computed live from the inputs and constants below. No figure is hard-coded; every number is derived. Sources are cited where applicable. Verified April 2026.
1 · User inputs (live)
state Selected stateRI
User selection
path RI program pathREG
User · RI only
utility MA utility territory—
User · MA only
Y Timeline (years)15 yrs
Slider · 1–20
B Battery count2 × 5.12 kWh
Slider · 1–8
N Portfolio units1
Portfolio mode only
2 · Core40 system constants (fixed)
Solar array size
3.28 kW
Core40 spec
Inverter capacity
6,000 W
Core40 spec
Battery unit capacity
5.12 kWh
Alpha 5 Pro datasheet
Renewable equipment value
$10,530
Internal cost model
Core40 purchase price
$117,000
Published list price
Salary benchmark (portfolio)
$50,000 / yr
Calculator convention
3 · State program seed values (verified April 2026)
RI · REG solar rate
$0.2723 / kWh · 15-yr lock
RI Energy
RI · Annual production (3.28 kW)
3,979 kWh / yr
PVWatts · RI insolation
RI · REG annual solar income
$1,083 / yr
3,979 × $0.2723
RI · REG upfront incentives
$1,600
RI Energy heat pump + HPWH rebates
RI · REF upfront incentives
$5,732
REF $2,132 + battery $2,000 + RI Energy $1,600
RI · REF solar income
$0 (net metering)
Bill savings — not quantified here
CT · RRES net rate
$0.2887 / kWh · 20-yr lock
$0.3289 gross − $0.0402 SEA · PURA
CT · Annual production
3,854 kWh / yr
PVWatts · CT insolation
CT · Annual solar income
$1,112 / yr
3,854 × $0.2887
CT · Upfront incentives
$2,560
ESS $250 × 10.24 kWh — verify post-Apr-2026
MA · SMART 3.0 rate
$0.03 / kWh · 20-yr lock
DOER · MA SMART 3.0
MA · Annual production
3,854 kWh / yr
PVWatts · MA insolation
MA · Annual solar income
$116 / yr
3,854 × $0.03
MA · Upfront incentives
$1,000
MA state income tax credit (Schedule SC)
4 · ConnectedSolutions seed values (per battery, annualized)
RI · per battery / yr
$413 low — $688 high
$225/kW summer + $50/kW winter · 5-yr term
CT · per battery / yr
$413 low — $688 high
~$225/kW · 10-yr term
MA Eversource · per battery / yr
$504 low — $840 high
$275/kW · 5-yr term
MA National Grid · per battery / yr
$413 low — $688 high
$225/kW · 5-yr term
MA Unitil · per battery / yr
$0
Unitil does not participate
Annual income scales linearly with battery count: B × per-battery rate. Default Core40 (B = 2) in RI: $825–$1,375 / yr.
5 · Active formulas (using current inputs)
Annual solar: annualKWh × solarRate = $1,083 / yr
Total solar: annual × min(Y, solarTermCap) = $16,245
Annual CS low: B × cs.low = $825 / yr
Annual CS high: B × cs.high = $1,375 / yr
Total CS low: annual CS low × Y = $12,375
Total CS high: annual CS high × Y = $20,625
Grand total low: upfront + total solar + total CS low = $30,220
Grand total high: upfront + total solar + total CS high = $38,470
Monthly equiv: (annual solar + annual CS) ÷ 12 = $159–$205 / mo
% of $117K: grand total ÷ $117,000 = 26–33%
6 · Method notes & caveats
Term caps. Solar income stops accruing after the program's contractual lock period ends: REG = 15 yrs, REF = 0 yrs (net metering only), RRES = 20 yrs, SMART 3.0 = 20 yrs. After the cap the system reverts to net metering — real value, not quantified here.
ConnectedSolutions term. Performance terms are RI 5 yrs · CT 10 yrs · MA 5 yrs. The calculator extrapolates CS income across the full user-selected timeline at locked rates; actual continuation past contract term is not guaranteed and would require re-enrollment.
Solar income precision. The verified RI REG annual solar income is $1,083.27 / yr ($0.2723 × 3,979). The calculator uses this exact figure; the campaign-published 15-yr total of "$15,750" rounds to $1,050 / yr. If you need the calculator's totals to match the campaign figure exactly, lock the annual rate at $1,050.
Unresolved items not used in calculator: RI $2,000 REF battery adder stacking with REG (pending verification with RI Commerce / RI Energy); CT ESS post-April 2026 exact terms; ConnectedSolutions exact post-season payment schedule; property and sales tax treatment of factory-built homes with integrated solar.
See it for yourself.
Book a tour of the Core40 model home in Rumford, RI.