Installed prices, system size and the cash-loan gap
- Lawrence Berkeley National Laboratory, U.S. Distributed Solar and Storage 2025 Data Update (Tracking the Sun), October 2025, covering installs through year-end 2024
Residential solar · United States
Home solar, with the arithmetic shown
What home solar costs per watt, what happened to the federal credit, and why exported power is worth different amounts by state. Every figure sourced and dated.
Cost, worked through Tax credit explained Quotes compared like for like
What does this site do?
Solar Panel Answers connects you with licensed local solar companies.
- Not a contractorWe do not sell, finance or fit panels, so nothing here depends on you signing.
- A source and a date on every numberFederal agencies, the EIA and the national laboratories, each checked 2026-08-18.
- Disagreements published, not resolvedWhere two national sources give different prices, both appear, with the reason.
- Two things you can do hereWork through the answer pages, or ask to be matched with a licensed local company.
How we are paid
We earn a referral fee from the company you are matched with. You pay us nothing for the match, and we do not set the price you are quoted.
Why do two national sources give different prices for the same system?
Because one measures what people paid and the other models what a system should cost to build. Lawrence Berkeley National Laboratory puts the 2024 median residential price at $4.0 per watt before any incentive; NREL's bottom-up benchmark for the first quarter of 2024 is $3.25 per watt. Neither is wrong.
- $4.0/WMedian price paid, 2024 installs
- $3.0–5.2/WMiddle 60% of those installs
- $3.25/WModelled benchmark, Q1 2024
- $1.2/WLoan median above cash median
NREL gives the reason itself: reported pricing is “more likely to include cost categories not within the cost benchmarks' scope, such as financing costs, roof upgrades, or service contracts”, and is based on national averages rather than representative configurations (NREL/TP-7A40-92536, January 2025). The LBNL figures are gross prices for host-owned systems, before any incentive or tax credit, in 2024 dollars per watt-DC.
The spread inside the LBNL data matters more than the gap between the two sources. The middle 60% of 2024 installs ran $3.0 to $5.2 per watt, and the split by payment method is wider still: a median of $3.5/W for cash purchases against $4.7/W for loan-financed systems. LBNL attributes that gap to dealer fees rolled into the up-front price the customer sees, and it has widened from $0.6/W in 2017 to $1.2/W in 2024.
Two more figures worth carrying into a sales conversation. Prices were essentially flat between 2023 and 2024, within ±$0.1/W in inflation-adjusted terms, and NREL describes its benchmark costs since 2021 as relatively flat, with ups and downs caused by market dynamics such as policy changes, tariffs and supply chain constraints. And roughly 80% of what you pay at the 2024 median is soft costs and balance-of-system rather than the panels themselves — which is why two quotes listing identical hardware need not be anywhere near each other.
Which parts of a solar quote are fixed nationally, and which change with your address?
Three layers, and only the first is the same everywhere: hardware and its warranties are national products, the value of exported power is set by state policy and utility tariff, and the production estimate belongs to your roof alone. A quote that blurs the three cannot be compared against another quote - the same rooftop system can be worth materially different amounts in two neighbouring states, or under two utilities in the same state, because the export credit is set by policy and tariff rather than by the panels.
National
The same wherever the roof is
2- Federal tax law§25D ended for expenditures made after 31 December 2025
- Warranties & degradationperformance warranty usually 20–25 years; product warranty most commonly 10–12 years (some as short as 5); output degrades 0.5%/yr (DOE) to 0.7%/yr (NREL modelling)
Federal statute and national-laboratory documents, not local practice.
State & utility
Set where you live, not by the equipment
2- Export creditnet metering, net billing, buy-all/sell-all or avoided cost, measured against the retail rate
- State incentives and interconnection rulesnot published here yet
Policymakers, regulators and utilities decide these collectively (NREL, updated 2026-02-20).
Your roof
Specific to the house
2- System & output7.2 kW median install in 2024 (middle 60% about 4–11 kW), modelled hour by hour from NSRDB weather data
- Consumption865 kWh a month for the average US residential customer in 2024
Only the last of these comes off a document you already own: your utility bill.
Why does the date an installation was finished decide the tax outcome?
Because completion is the statutory test, not payment. IRC §25D(e)(8)(A) treats an expenditure as made “when the original installation of the item is completed”. P.L. 119-21, enacted 4 July 2025, ended the Residential Clean Energy Credit for expenditures made after 31 December 2025 — so a 2025 deposit with a 2026 finish gets nothing.
The credit was 30% of the cost of purchasing, assembling and installing qualifying equipment, and it applied from 2022 through 31 December 2025. The IRS states it plainly: “The credit is not available for any property placed in service after December 31, 2025.” The 2025 Instructions for Form 5695 put the same rule in the taxpayer's own words.
What the repeal did not touch is the carryforward. A qualifying expenditure made before the end of 2025 can still carry unused credit forward, and carryforwards may be used indefinitely until the entire amount is taken. The credit is nonrefundable, so it never pays out beyond your tax liability. CRS works its own example: a $30,000 system earns a $9,000 credit, and a taxpayer owing $7,000 goes to zero and carries $2,000 forward.
That carryforward mattered to most claimants rather than a few. Of roughly 1.4 million taxpayers who qualified in tax year 2023, 46.5% used the entire credit that year, 43.3% carried part of it forward and 10.2% carried all of it forward.
How big is a typical home system, and what does a house actually use?
The median US residential system installed in 2024 was 7.2 kW, with the middle 60% of installs between about 4 and 11 kW. The mean, 9.3 kW, is pulled up by large systems. The average US residential customer bought 865 kWh a month in 2024 at 16.5 cents per kilowatt-hour.
Keep the distinction straight, because sales material rarely does. 7.2 kW is an observation of what households installed; 7.9 kW-DC is a configuration NREL models for its cost benchmark; neither is a recommendation for your roof. California's median was 5.7 kW while most other states sat above 7 kW, which is a reminder that the typical system is a local quantity too.
EIA raises its own caveat on the consumption figure, and it is the one a solar reader needs: these are electricity purchases, not consumption. Net-metered PV reduces purchases, so in states with a lot of rooftop solar, what households actually use is higher than the number shows.
Sources
Every figure on this page traces to one of these. Ranges are reported as ranges.
Cost benchmark and why the two price sources differ
- NREL/TP-7A40-92536, Documenting 15 Years of Reductions in U.S. Solar Photovoltaic System Costs, January 2025, Q1 2024 benchmark
Federal credit, the completion test and carryforward
- Congressional Research Service Insight IN12611, 2025-09-25
- IRS, Residential Clean Energy Credit
- IRS FS-2025-05, 2025-08-21
- 2025 Instructions for Form 5695
Export compensation mechanisms
- NREL State, Local & Tribal Governments, Energy Compensation Mechanisms for Distributed Generation, last updated 2026-02-20
Warranty terms and degradation rates
- NREL/Sandia/SunSpec, NREL/TP-7A40-73822, December 2018
- DOE FEMP, DOE/GO-102021-5627, December 2021
Household electricity purchases, bills and rates
- EIA Today in Energy, 2025-05-12
- EIA FAQ, How much electricity does an American home use?
How it works
From “is it worth it?” to a number you can check
1
Start with your power bill
The kilowatt-hours you used over the last year is the number every honest quote is built from. Without it, any price is a guess.
2
See what the roof can actually make
Pitch, orientation and shade decide how much of that usage a system can realistically cover. This is the step door-to-door pitches skip.
3
Put the quotes on one basis
Cash, loan and lease are three different products. Compare system size and total price first, then compare the financing separately.
4
Matched with a licensed local company
The work is done by licensed local solar companies. We do not sell panels and we do not fit them.
Who this is for
Homes and small commercial
Homeowners
Owner-occupied roofs
The main case: you own the roof, you pay the utility bill, and the decision turns on how long you plan to stay in the house.
Small commercial
Premises & landlords
A commercial roof changes the arithmetic rather than the hardware - different tariff, different tax position, different depreciation.
What you are buying
The parts behind one price
A residential quote arrives as a single number covering all of this. Knowing which part is which is how two quotes that look nothing alike become comparable.
How we work
What to expect from this site
Every figure here carries its source and the date it was checked.
Answer first, then the working
Each page opens by answering its own question in a couple of sentences, then shows the arithmetic underneath for anyone who wants to check it.
Ranges, not one confident number
Solar pricing moves with the roof, the state, the utility and the financing. A single national figure fits almost nobody, so we publish the spread our sources support.
We say when the maths does not work
A shaded roof on a low tariff can be a poor buy. That is a legitimate answer to the question and you will find it here rather than a reason to keep reading.
We are not the contractor
We do not sell panels and we do not fit them, so nothing here depends on you signing. Licensed local companies do the work.
Questions
Frequently asked
The questions homeowners actually ask before they sign anything.
Is the 30% federal solar credit still available?
No. P.L. 119-21, enacted 4 July 2025, ended the Residential Clean Energy Credit for expenditures made after 31 December 2025, and the IRS states that the credit is not available for property placed in service after that date. The 30% rate applied to installations from 2022 through 2025.
I paid a deposit in 2025 and the installer finished in 2026. Do I still get the credit?
No. Under §25D(e)(8)(A) an expenditure is treated as made when the original installation is completed, so the IRS treats a 2026 completion as an expenditure made after 31 December 2025. The payment date is not the test, which is the part consumers most often get wrong.
Why is the loan price higher than the cash price?
In 2024 the median cash purchase came to $3.5 per watt and the median loan-financed system to $4.7 per watt. LBNL attributes the difference to dealer fees rolled into the up-front price the customer sees. The gap has widened from $0.6 per watt in 2017 to $1.2 per watt in 2024.
Why will you not give me a total price for my house?
Because no source we hold publishes one. The national figures are per watt, and the dollar total depends on system size, which spanned roughly 4–11 kW for the middle 60% of 2024 installs. A per-watt figure multiplied by a stated system size is a number you can check; a headline total is not.
What is the most useful thing to ask an installer?
The system size in kilowatts-DC and the total price before financing, so you can divide one by the other and compare the result against the $4.0 per watt median for 2024 installs. A monthly payment answers neither question and hides both.
Does Solar Panel Answers install panels?
No. Solar Panel Answers connects you with licensed local solar companies. We are not a solar contractor, we do not sell or fit equipment, and we do not set the price you are quoted.