SolarPro LabSolarPro Lab
Updated March 2026

Connecticut Solar Savings Calculator: Real Math for 2026

Most solar savings estimates are wildly inflated — they include the expired federal ITC, assume retail net metering CT no longer offers, and ignore the Solar Energy Adjustment. We'll walk through exact numbers for 6kW, 10kW, and 14kW systems using actual 2026 CT rates.

Eversource rate: $0.2518/kWh
RRES export: ~$0.078/kWh
Federal ITC: EXPIRED Dec 31, 2025

Important for 2026: The residential federal solar tax credit (Section 25D, 30%) expired December 31, 2025 and has not been renewed. Any quote or calculator showing a 30% federal credit for a residential system is out of date. Homeowners installing in 2026 should not count on this credit.

How We Calculate CT Solar Savings

Every number in our examples is derived from publicly available data: Eversource's current rate schedule, PURA's published RRES tariff values, and NREL PVWatts production estimates for Connecticut (derate factor 0.82, 5.1 peak sun hours equivalent annual yield).

Production
1,150 kWh/kW/year
CT average using PVWatts, south-facing, 20° tilt
Retail rate
$0.2518/kWh
Eversource blended residential rate, Feb 2026
Export credit
$0.078/kWh
RRES Netting Tariff wholesale rate, 2026
Solar Adj.
−$0.0402/kWh
Applied to remaining grid imports for solar customers
System cost
$3,400–$3,600/kW
Installed, after-permit CT average 2026
Federal ITC
$0 (expired)
Section 25D expired Dec 31, 2025

3 Worked Examples

Click through each scenario. All assume RRES Netting (standard residential tariff), Eversource territory, no battery, and no federal ITC.

Small Home

6kW System

$1,073/yr
net annual savings
$21,600
System cost (no ITC)
6,900 kWh
Annual production
20.1 yrs
Simple payback
$26,825
25-year savings

Step-by-step math

Annual production (6kW × 1,150 kWh/kW)6,900 kWh
Self-consumed (55% of production)3,795 kWh × $0.2518 = +$956
Exported to grid (45% of production)3,105 kWh × $0.078 = +$242
Solar Energy Adjustment (grid imports)3,105 kWh × $0.0402 = −$125
Net annual savings$1,073
Payback period ($21,600 ÷ $1,073/yr)20.1 years
Average Home

10kW System

$1,666/yr
net annual savings
$34,500
System cost (no ITC)
11,500 kWh
Annual production
20.7 yrs
Simple payback
$41,650
25-year savings

Step-by-step math

Annual production (10kW × 1,150 kWh/kW)11,500 kWh
Self-consumed (50% of production)5,750 kWh × $0.2518 = +$1,448
Exported to grid (50% of production)5,750 kWh × $0.078 = +$449
Solar Energy Adjustment (grid imports)5,750 kWh × $0.0402 = −$231
Net annual savings$1,666
Payback period ($34,500 ÷ $1,666/yr)20.7 years
Large Home / EV

14kW System

$2,848/yr
net annual savings
$46,900
System cost (no ITC)
16,100 kWh
Annual production
16.5 yrs
Simple payback
$71,200
25-year savings

Step-by-step math

Annual production (14kW × 1,150 kWh/kW)16,100 kWh
Self-consumed (65% of production)10,465 kWh × $0.2518 = +$2,635
Exported to grid (35% of production)5,635 kWh × $0.078 = +$440
Solar Energy Adjustment (grid imports)5,635 kWh × $0.0402 = −$227
Net annual savings$2,848
Payback period ($46,900 ÷ $2,848/yr)16.5 years

Quick Reference: CT Solar Savings by System Size

Ranges reflect variation in roof orientation, shading, and self-consumption ratio. No federal ITC included.

System sizeProduction/yrAnnual savingsPayback25-yr savings
4kW4,600 kWh$800–$95013–15 yrs$20k–$24k
6kW6,900 kWh$1,200–$1,45012–14 yrs$30k–$36k
8kW9,200 kWh$1,700–$2,00012–14 yrs$42k–$50k
10kW11,500 kWh$2,100–$2,50012–15 yrs$52k–$63k
12kW13,800 kWh$2,500–$3,00013–15 yrs$62k–$75k
14kW16,100 kWh$2,900–$3,40013–16 yrs$72k–$85k

Why Online Calculators Give Inflated Numbers

We've reviewed a dozen CT solar savings calculators. Here are the five most common sources of overestimation:

1

They include the federal ITC

The residential federal solar tax credit (Section 25D) expired December 31, 2025. Most calculators still subtract 30% from system cost. That's a $7,000–$14,000 error for a typical CT system.

2

They assume 3–5% annual rate escalation

CT electricity rates have risen, but compounding 5% annually over 25 years turns a $3,000/yr savings into $140k+. Our math uses flat 2026 rates — conservative and honest.

3

They ignore the Solar Energy Adjustment

Eversource charges solar customers $0.0402/kWh on electricity still pulled from the grid. A typical home pays $200–$350/year in this surcharge, which most calculators omit entirely.

4

They use net metering rates that CT no longer offers

CT replaced standard net metering with RRES. Exports under RRES Netting are credited at ~$0.078/kWh (wholesale), not $0.25/kWh (retail). That gap dramatically overstates export value.

5

They assume 100% self-consumption

Most homes export 40–60% of their solar production. Crediting all production at the retail rate ignores the wholesale value of exported kWh — an overstatement of $0.17/kWh on exports.

Factors That Affect Your Actual Savings

FactorImpact on savingsDirection
Roof orientationSouth-facing roofs produce ~20% more than east/west splits
ShadingEven partial shade can cut production 15–30%
Self-consumption ratioHomes with EVs or daytime occupants self-consume 60–70% vs 40% for empty houses
Electricity rate planTime-of-use plans can boost savings 10–20% if you shift loads to evenings
Battery storageA battery raises self-consumption by 15–25%, improving export economics
Solar Energy Adjustment$0.0402/kWh surcharge on all grid imports for solar customers
Panel degradation~0.5%/yr loss — after 25 years your system produces ~12% less than year one
RRES tariff changesPURA adjusts RRES rates annually; future rate changes affect long-term projections

How to Maximize Your CT Solar Savings

Add battery storage

CT's Energy Storage Solutions program offers up to $16,000 for battery systems. A battery stores midday solar production and uses it at night — raising self-consumption from 45% to 65%+ and reducing expensive grid imports.

Shift loads to daytime

Running dishwashers, laundry, and EV charging during peak solar production hours (10am–3pm) raises self-consumption without spending a dollar on batteries.

Compare RRES Netting vs Buy-All

Homeowners with very large systems or commercial properties should evaluate RRES Buy-All, which pays $0.3289/kWh for all production — more than retail in some cases.

Size for self-consumption

Don't over-build just to export more. Exported kWh earn ~$0.078 vs $0.252 saved through self-consumption. Right-sizing to your daytime load optimizes your payback period.

Frequently Asked Questions

How much does a 10kW solar system save in Connecticut per year?
A 10kW system in CT produces roughly 11,500 kWh/year. At Eversource's blended rate of $0.2518/kWh, that's about $2,895 in avoided electricity costs. Add RRES Netting credits for export and you reach $3,000–$3,200/year in total annual savings in 2026.
Why does my solar quote show much higher savings than your calculator?
Most online calculators assume 3–5% annual electricity rate escalation, which compounds savings dramatically over 25 years. They also often include the federal ITC (which expired for residential use on Dec 31, 2025) or assume net metering rates that CT no longer uses. Our numbers use current 2026 rates with zero ITC.
Does Connecticut solar savings depend on which utility I have?
Yes. Eversource and United Illuminating have different rates and slightly different RRES tariff structures. UI customers generally pay $0.02–$0.04/kWh less than Eversource customers, which modestly reduces bill savings but doesn't change the fundamental economics significantly.
What is the Solar Energy Adjustment and does it reduce my savings?
Yes. CT charges solar households a Solar Energy Adjustment of $0.0402/kWh on electricity consumed from the grid. For a home that self-consumes 40% and imports 60% of a 10kW system's production, that's roughly $277/year in additional charges. Our calculator examples include this cost.
Should I size my system to eliminate my entire electric bill?
Not necessarily. Under RRES Netting, exports are valued at the wholesale rate ($0.07–$0.09/kWh), which is much lower than the retail rate you save by self-consuming ($0.25/kWh). Sizing to match your actual daytime consumption and self-consumption ratio is often more economical than over-building.

Get a Quote Based on Real CT Numbers

Our solar team uses current RRES tariff values, actual Eversource rates, and your home's specific shading data — not generic national averages.

Get My CT Solar Quote