NerdyWatts

Solar payback · KY

Is solar worth it in Kentucky?

A 7 kW rooftop system near Louisville produces about 9,486 kWh a year. Priced against 10 current residential tariffs in Kentucky, payback runs from 10 years on the best of them to 49 on the worst.

No federal tax credit applies to a purchased system. Section 25D ended on December 31, 2025. Leases and power-purchase agreements can still reach the business credit (48E) through 2027, but it is claimed by the system's owner, not by you. Every figure on this page assumes no federal credit and no state or utility incentive.
10 yearsshortest payback, on the best tariff
1,355kWh per kW per year
#31of 52 states measured
54%used on site, not exported
$21,000system cost at $3.00/W

Why the tariff matters more than the panels

Two households in Kentucky with identical roofs and identical systems can see paybacks 10 and 49 years apart, purely because they are on different tariffs. Solar produces at midday; households consume in the evening. Only 54% of what these panels make is used as it is made — the rest is exported, and what an exported kWh earns is set by the tariff and by state net metering rules, not by the hardware.

That is why the figures here are computed hour by hour against each real tariff rather than by taking a bill and assuming solar removes a share of it. How this is modeled →

Payback by tariff in Kentucky

7 kW system at $3.00/W, household using 1000 kWh a month, no incentives. A range means the export credit is not filed with the tariff and the outcome depends on net metering rules — 10 of 10 tariffs here belong to a utility that reports residential net metering.

UtilityTariffStructure Annual savingPayback
Kentucky Utilities Co Residential Service Flat $1,124–$2,065 10–19y
Kentucky Utilities Co Residential Time-of-Day Energy Service Time-of-use $1,047–$2,018 10–20y
Kentucky Power Co Residential Service Load Management - Time of Day - RSLMTOD Time-of-use $704–$1,255 17–30y
Kentucky Power Co Residential Time-of-Day Service - RSTOD Time-of-use $704–$1,255 17–30y
Kentucky Power Co Experimental Residential Time-of-Day 2 Service - RSTOD2 Time-of-use $706–$1,249 17–30y
Kenergy Corp Residential Service (Schedule 1) Flat $663–$1,218 17–32y
Kentucky Power Co Residential Service - RS Flat $659–$1,211 17–32y
Louisville Gas & Electric Co RS - Residential Service Flat $536–$985 21–39y
Louisville Gas & Electric Co Residential Time-of-Day Energy Service Time-of-use $498–$961 22–42y
Owen Electric Coop Inc Schedule I - Residential Flat $432–$793 26–49y

Your roof, your numbers

Change the usage, system size and installed cost, and every Kentucky tariff is priced again.

Price it for your own system

What would change this

Your roof. Production is modeled for Louisville on a south-facing array at 20° tilt. Shading, orientation and pitch all move it, and solar resource varies within Kentucky itself.

Your usage pattern. A household at home during the day self-consumes more and exports less, which shortens payback wherever export credit is poor.

Rising rates. These figures hold today's prices flat. Electricity prices have been rising, and every rise shortens payback — so treat these as a conservative bound.

State and local incentives. Not included here, and in some states they are worth more than the federal credit was. Check your state energy office before deciding.

Guides to solar payback

All guides

  1. Guide · 4 min

    Why a smaller solar system pays back faster

    Doubling your panel count does not double your savings. On a real Georgia Power tariff, a 3 kW system pays back in 13 years and a 12 kW system takes 21 to 41 — and past a certain size, extra panels cannot save you anything at all.

  2. Guide · 3 min

    Where homes net-meter rooftop solar, and where almost none do

    Utilities report 5.5 million net-metered home solar systems, 41 per 1,000 households. Hawaii has 233; Tennessee and Alabama almost none.

  3. Guide · 3 min

    Solar in 2026, without the federal tax credit

    Section 25D ended on December 31, 2025. A home solar system bought in 2026 gets no federal credit at all — not a reduced one — and most payback advice still online predates that.

  4. Guide · 4 min

    Some utilities charge households for their peak demand

    59 household tariffs at 27 utilities charge for peak demand, typically $8.58 per kW a month. From 2027, southern Nevada's homes will pay one by the day.

  5. Guide · 3 min

    When is electricity most expensive? It depends on your utility

    Across 95 utilities with time-of-use rates we found 49 different weekday peak windows. Nearly all include 5 to 6 pm; little else is shared.