US residential solar · 2026 data

How Many Solar Panels Does a 1,100 sq ft House Need?

Q: How much does solar cost for a 1,100 sq ft house in 2026?

Installed residential solar typically costs $2.50–$3.50 per watt before incentives. EnergySage marketplace quotes average about $2.60 per watt nationally, while Lawrence Berkeley National Laboratory data puts the 2024 cash-purchase median near $3.50 per watt. For a 5.6 kW system that is about $14,000–$19,600, or $16,800 at our $3.00-per-watt base case. Prices vary by state, roof complexity and equipment, so compare at least three itemized quotes on price per watt.

Q: Is the 30% federal solar tax credit still available in 2026?

Not for homeowners who buy a system with cash or a loan. The One Big Beautiful Bill Act ended the Section 25D Residential Clean Energy Credit for expenditures made after December 31, 2025, and the IRS treats an expenditure as made when installation is completed. Systems finished by that date can be claimed on the 2025 return, and unused credit can carry forward. Leased or PPA systems can still benefit indirectly, because the provider may claim the Section 48E business credit, but that credit generally requires the system to be in service by December 31, 2027 unless construction began by July 4, 2026. Confirm your situation with a tax professional.

Q: How long does it take for solar to pay for itself?

In our base case (5.6 kW, $3.00 per watt, 4.5 sun hours, 18.3¢ per kWh, no federal credit, 0.5% yearly output decline), cumulative savings reach the system cost in about 13 years. That is about 9 years at 6.5 sun hours and about 17 years at 3.5 sun hours. If electricity rates rise 3% a year, the base case pays back in about 11 years. Higher rates and state incentives shorten payback, while lower export credits under newer net-metering rules lengthen it.

Q: Is solar worth it for a small 1,100 sq ft house?

It can be, if your electricity bill is high enough and you will stay in the home past the payback period. In our base case a 5.6 kW system saves about $112 per month in year 1 and about $14,900 net over 25 years at flat rates. Savings depend on how many kWh you use, your utility rate and how exports are credited, not on house size. Homes with low usage save less in absolute dollars, so improve efficiency first, then size the system to your real usage and compare a smaller system, a loan, or a lease/PPA.

Est. net savings

$14,900

Over 25 Years (Model, Flat Rates) · no federal credit

$16,800 Base-case cost (no federal credit)

13 yrs Payback (base case)

5.6 kW System size

Typical result:

~14 panels (400 W)
5.6 kW system
$14,000–$19,600 before incentives
~13 year payback

✓ EIA rates & NREL sun data ✓ 2026 federal policy applied ✓ Open methodology

Updated September 29, 2026 · 9 min read ·By Green Energy Calculators Editorial Team

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25 years without solar vs with solar

Assumes 3%/yr rate increases, 0.5%/yr panel degradation and no federal tax credit (the 30% §25D credit ended for systems installed after Dec 31, 2025). How we calculate

Without solar

25-year utility bills

$31,720

Rates rise ~3% per year

With solar

System cost + remaining bills

$16,800

Installed cost, no federal credit

Difference

Estimated 25-year net

+$14,920

Before any state or utility incentives

Author Green Energy Calculators Editorial Team

Editorial policy No paid placements

Last updated Sep 29, 2026

Data approach EIA rates · NREL sun hours · 2026 federal policy · methodology

A 1,100 sq ft house (about 102 m²) that uses 600 kWh per month needs roughly 14 solar panels (400 W each, about 5.6 kW) to cover all of its electricity at 4.5 peak sun hours per day. That falls to about 10 panels in very sunny places and rises to about 18 in cloudy ones. The most important 2026 change: the 30% federal tax credit for homeowner-owned solar ended on December 31, 2025, so the installed price is now the net price unless your state or utility offers incentives.

Last updated September 29, 2026. Figures use U.S. units; 1 sq ft = 0.093 m².

How to Calculate Solar Panel Count for a 1,100 sq ft Home

House size is a weak predictor of solar needs. Electricity use is what matters. The U.S. Energy Information Administration (EIA) 2020 Residential Energy Consumption Survey reports that homes of 1,000 to 1,499 sq ft used an average of 32.1 million Btu of electricity per year, which is roughly 780 kWh per month (our conversion). Individual homes vary widely with climate, heating fuel and appliances, so use the annual kWh on your own utility bill.

The formula:

Panels = (Monthly kWh × 12) ÷ (Peak sun hours × 365 × 0.80) ÷ Panel kW

The 0.80 factor is a conservative allowance for inverter, wiring, temperature and soiling losses. NREL’s PVWatts calculator models these losses for your exact address.

Worked example: 600 kWh/month at 4.5 sun hours:

Annual use: 600 × 12 = 7,200 kWh
System size: 7,200 ÷ (4.5 × 365 × 0.80) = 5.48 kW
Panels at 400 W: 5.48 ÷ 0.4 = 13.7, so 14 panels (5.6 kW)

The table below shows how the count changes with usage and sunshine (400 W panels, rounded up).

Monthly use	3.5 sun hrs	4.5 sun hrs	5.5 sun hrs	6.5 sun hrs
400 kWh	12	10	8	7
600 kWh	18	14	12	10
800 kWh	24	19	15	13

Peak sun hours are annual averages. Published figures vary by source and roof tilt, but Seattle is generally cited near 3.5 and Phoenix near 6.5 to 6.7. Look up your address in PVWatts for a precise figure.

Panels needed by sunshine and usage. A 600 kWh/month home needs 14 panels (5.6 kW) at 4.5 peak sun hours and 18 at 3.5. Calculated with the formula above (0.80 system factor, 400 W panels, rounded up). Model, not a measurement for any address.

Chart summary: For a home using 600 kWh per month, the panel count falls from 18 at 3.5 sun hours to 10 at 6.5 sun hours. Usage matters as much as sunshine: an 800 kWh home at 4.5 sun hours needs 19 panels, almost twice the 10 panels of a 400 kWh home in the same spot. Compare quotes by system size in kilowatts, not panel count, because panel wattage varies from about 370 W to 440 W.

Use our solar system size calculator to run these numbers for your address and usage.

Run the numbers for your state

The savings calculator loads your state's average electricity rate, sun hours and net-metering rule. Then enter your own bill and installer quote.

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What Does a Solar System for a 1,100 sq ft House Cost in 2026?

Installed residential solar generally costs $2.50–$3.50 per watt before incentives in 2026. EnergySage marketplace data averages about $2.60 per watt nationally, with state averages that differ (for example, about $2.25 per watt in Texas and $2.76 in New York as of September 2026). Lawrence Berkeley National Laboratory’s Tracking the Sun data puts the median for cash-purchased systems installed in 2024 near $3.50 per watt. The gap reflects who is measured: marketplace quotes are competitive bids, while Berkeley Lab data covers what buyers actually paid across many installers. Small systems also tend to cost more per watt than large ones.

Our base case uses the midpoint, $3.00 per watt, for a 5.6 kW system: $16,800.

System size	Panels (400 W)	Cost at $2.50/W	Cost at $3.50/W
3.6 kW	9	$9,000	$12,600
4.8 kW	12	$12,000	$16,800
5.6 kW	14	$14,000	$19,600

The chart below plots the same range, so you can see how much the $ per watt you negotiate matters more than the panel count.

Installed cost by system size, before incentives. A 5.6 kW system runs $14,000 at $2.50/W and $19,600 at $3.50/W. Source: EnergySage marketplace and Berkeley Lab (LBNL) price ranges, 2026; no federal credit applies to homeowner-owned systems.

Chart summary: The gap between the low and high price is $3,600 on a 3.6 kW system and $5,600 on a 5.6 kW system, so quote quality moves the total more than a two-panel size change does. Each added 400 W panel costs roughly $1,000–$1,400 installed at $2.50–$3.50 per watt. Ask every installer for an itemized price per watt.

These are gross prices. There is no federal credit to subtract for homeowner-owned systems installed in 2026. The IRS states that the Residential Clean Energy Credit is not available for property placed in service after December 31, 2025. A few exceptions and alternatives are worth knowing:

Installations completed by December 31, 2025 can claim the 30% credit on the 2025 return (Form 5695), and unused credit carries forward. The IRS treats an expenditure as made when installation is completed, not when you pay.
Lease and PPA systems may still benefit from the Section 48E business credit, which the provider claims. Under the 2025 law, solar projects that did not begin construction by July 4, 2026 generally must be placed in service by December 31, 2027. Check whether any savings are passed on to you and how long the offer is valid. See EnergySage’s overview.
Many states, utilities and localities offer rebates, tax credits, or property and sales tax exemptions. Check the DSIRE database for your address.

Equipment choices move the price. String inverters cost less; microinverters or optimizers cost more but help on partly shaded roofs. Battery storage adds substantial cost, and the homeowner-owned battery credit ended with the same law, so price it as a separate option. For related sizing, see our guides for an 800 sq ft house and a 1,200 sq ft house.

Estimate your incentive position with our solar tax credit calculator.

Solar vs utility company · 25-year comparison

25-year totals: 3%/yr rate increases, 0.5%/yr degradation, no federal credit. Methodology

Total utility payments

$31,720

Total solar cost (installed + remaining bills)

$16,800

Net savings

+$14,920

Avg. monthly difference

+$112/mo

See my savings →

How Many Solar Panels Fit on a 1,100 sq ft Roof?

A typical 400 W panel measures about 65 × 39 inches (1.65 × 1.0 m), or 17.6 sq ft (1.6 m²). Fourteen panels need roughly 250 sq ft (23 m²) of unshaded roof. Whether your roof can host that depends on layout, not on the 1,100 sq ft living-area figure: a two-story home has a smaller roof footprint, and chimneys, vents, dormers and fire-code setbacks reduce usable space. A roof assessment or satellite layout from an installer settles it.

South-facing planes at a moderate pitch usually produce the most energy in the US. East- and west-facing planes produce less per panel, so you may need one or two extra panels for the same annual output. Shade on even one panel can cut string output unless you use microinverters or optimizers. If the roof cannot hold a full-offset system, a smaller system still lowers your bill; it just covers a smaller share of your usage.

How Long Does Solar Payback Take for a 1,100 sq ft House?

Payback depends on system price, sunshine and what each kWh is worth. The EIA reports a U.S. average residential price of 18.3¢ per kWh for June 2026 (Electric Power Monthly, Table 5.6.A), with state averages ranging from about 13¢ in Nevada to about 53¢ in Hawaii.

Our base case:

5.6 kW system at $3.00 per watt = $16,800 (no federal credit)
4.5 sun hours and a 0.80 system factor = about 7,360 kWh in year 1
Value at 18.3¢ per kWh = about $1,347 in year 1 (about $112 per month)
Output falls 0.5% per year, the median rate in NREL’s Jordan and Kurtz degradation review
Every kWh is credited at the full retail rate, and the rate stays flat

That gives cumulative savings equal to the system cost in about 13 years (12.9). Payback scales with sunshine at the same price and rate:

Peak sun hours	Year-1 output	Year-1 savings	Payback	Net savings after 25 years
3.5	5,723 kWh	$1,047	16.7 years	$7,871
4.5	7,358 kWh	$1,347	12.9 years	$14,920
5.5	8,994 kWh	$1,646	10.5 years	$21,969
6.5	10,629 kWh	$1,945	8.8 years	$29,018

25-year cash flow, 5.6 kW system at $16,800. Flat 18.3¢/kWh (EIA, June 2026) breaks even in year 13 and nets $14,920 by year 25; with 3% yearly rate increases it breaks even in year 11 and nets $29,107. Scenario model, no federal credit, excludes financing and maintenance.

Chart summary: With flat electricity rates, the system breaks even in year 13 and shows about $14,900 in cumulative net savings by year 25. If rates rise 3% per year (an illustrative assumption, not a forecast), it breaks even in year 11 and nets about $29,100. The real result depends on your rate, how your utility credits exports, and whether you finance. Under reduced-export-credit rules such as California’s net billing tariff (in effect since April 2023), savings can be lower than the full-retail-rate assumption used here.

Check your utility’s export rules and your state’s programs in DSIRE, then use our solar payback calculator.

Is Solar Worth It for a 1,100 sq ft House in 2026?

Solar is most likely to pay off when your bill is high relative to your roof, your rates are above average, your utility credits exports at or near retail, and you plan to stay in the home for at least the payback period. Without the federal credit, the margin is thinner than older guides suggest, so local rates, incentives and quote quality matter more.

It is less compelling for heavily shaded roofs, roofs needing replacement within a few years, very low usage, and utilities with weak export credits. In those cases a smaller system, efficiency upgrades first (LED lighting, air sealing, efficient appliances), or a lease/PPA may fit better. Each kWh you avoid using reduces the system size you need to buy.

Get at least three itemized quotes, compare price per watt and warranty terms, and confirm current incentives before signing. Use our solar savings calculator to test your own numbers.

Method and sources: panel counts and payback are our own calculations from the formulas and assumptions shown in this article (0.80 system factor, 0.5% annual output decline, $3.00 per watt, 18.3¢ per kWh, flat rates unless stated). They are estimates, not quotes. Data referenced: U.S. Energy Information Administration (Electric Power Monthly, June 2026; 2020 Residential Energy Consumption Survey, Table CE2.1); IRS Residential Clean Energy Credit page and One Big Beautiful Bill FAQs; EnergySage marketplace pricing; Lawrence Berkeley National Laboratory, Tracking the Sun; NREL PVWatts and Jordan and Kurtz, Photovoltaic Degradation Rates; DSIRE. This guide is general information, not financial, tax or legal advice. Last reviewed September 29, 2026.

Frequently asked questions

Direct answers for US homeowners — sized for a $110/month electric bill.

How many solar panels does a 1,100 sq ft house need?

It depends on electricity use and sunshine, not square footage. A home using 600 kWh per month needs about 14 panels (400 W each, 5.6 kW) at 4.5 peak sun hours per day. The same home needs about 10 panels in Phoenix-like sun (6.5 hours) and about 18 in Seattle-like conditions (3.5 hours). A home using 400 kWh per month needs 7 to 12 panels across that same range, and one using 800 kWh needs 13 to 24. Use the annual kWh on your own utility bill and your address in NREL's PVWatts for a precise count.

How much does solar cost for a 1,100 sq ft house in 2026?

Is the 30% federal solar tax credit still available in 2026?

How long does it take for solar to pay for itself?

Is solar worth it for a small 1,100 sq ft house?

Popular state solar guides

Electricity rates and incentives vary — see data for your state.

CA California 33.25¢/kWh · 5.8h sun TX Texas 16.06¢/kWh · 5.6h sun FL Florida 15.3¢/kWh · 5.7h sun AZ Arizona 15.44¢/kWh · 6.5h sun NC North Carolina 14.94¢/kWh · 5.2h sun NY New York 29.38¢/kWh · 4.3h sun MA Massachusetts 30.14¢/kWh · 4.2h sun CO Colorado 16.72¢/kWh · 5.5h sun

View all 50 states →

How these numbers were calculated

Electricity rate: 18.19¢/kWh — US average residential price. Source: EIA Electric Power Monthly, Table 5.6.B (year-to-date through July 2026), residential average retail price (July 2026) (EIA)
Solar production: 4.5 peak sun hours/day × 0.82 system derate. Approximate state-average daily solar resource (peak sun hours) based on NREL solar resource data (NSRDB); not location-specific — use NREL PVWatts for an address-level estimate. (NREL PVWatts)
Installed price: $3.00 per watt before incentives. Blended 2026 US residential installed price used by this site; EnergySage marketplace reported about $2.60/W (mid-2026); full-market medians are higher.
Federal tax credit: $0 for homeowner-owned systems installed in 2026 — the 30% §25D credit ended Dec 31, 2025 (IRS)
Net metering: National blend — solar assumed to offset 75% of the bill (87% in full-retail net-metering states, 55–70% elsewhere).
Model: Version 2026.10 · 3%/yr electricity price escalation · 0.5%/yr panel degradation · simple payback = installed cost ÷ year-1 savings
Policy checked: September 29, 2026 · Full methodology · Report an error

Estimates only — not tax, legal or financial advice. Get at least three installer quotes and confirm incentives with your utility and a tax professional.

25 years without solar vs with solar

How to Calculate Solar Panel Count for a 1,100 sq ft Home

Run the numbers for your state

What Does a Solar System for a 1,100 sq ft House Cost in 2026?

Solar vs utility company · 25-year comparison

How Many Solar Panels Fit on a 1,100 sq ft Roof?

How Long Does Solar Payback Take for a 1,100 sq ft House?

Is Solar Worth It for a 1,100 sq ft House in 2026?

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Popular state solar guides

How these numbers were calculated