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
Data approachEIA rates · NREL sun hours · 2026 federal policy · methodology
Last updated October 3, 2026.
A home using 60 kWh per day needs roughly a 15 kW solar system, about 38 panels rated at 400 W, at U.S.-average sunshine. That ranges from about 29 panels in Phoenix to 48 in Seattle. The system costs roughly $39,500–$53,200 before incentives in 2026, and because the 30% homeowner tax credit (Section 25D) ended on December 31, 2025, buyers should not count on a federal credit.
For scale, 60 kWh per day equals 1,800 kWh per month, or 21,900 kWh per year. According to the U.S. Energy Information Administration, the average U.S. residential customer used 10,791 kWh in 2022, about 29.6 kWh per day. A 60 kWh/day home therefore uses roughly twice the national average, which is common with electric heating, a pool, EV charging, or a large house. Three variables drive the final numbers: the peak sun hours at your address, your usable roof area, and your utility’s rules for crediting solar exports.
⚡ System Size
How Many Solar Panels Do You Need for 60 kWh Per Day?
Use this formula: daily kWh ÷ peak sun hours ÷ 0.80 = system size in kW. The 0.80 factor is a conservative planning allowance for inverter losses, wiring, heat, and soiling. Divide the result by the panel wattage (0.4 kW for a 400 W panel) to get the panel count.
Peak sun hours below come from NREL PVWatts v8 averages. Your exact address will differ, so confirm it in NREL’s PVWatts calculator.
Solar system sizing for a 60 kWh/day home
Location
Peak sun hours/day
Raw kW (60 ÷ sun hours)
System kW (÷ 0.80)
Panels (400 W)
Phoenix, AZ
6.54
9.2
11.5
29
U.S. average
4.98
12.1
15.1
38
Boston, MA
4.70
12.8
16.0
40
Seattle, WA
3.95
15.2
19.0
48
A Seattle home needs about 65% more solar capacity than a Phoenix home to produce the same 60 kWh per day (19.0 kW vs. 11.5 kW), because Seattle gets 3.95 peak sun hours against Phoenix’s 6.54. Most U.S. locations fall between 15 and 16 kW.
At 400 W per panel, a 15.2 kW system uses 38 panels. Residential panels typically measure roughly 18–21 square feet each, so plan on about 700–800 square feet of unshaded roof. A ground mount, or an east/west split array, can substitute when a roof is too small. Many installers suggest sizing 5–10% above your calculated need if you plan to add an EV or heat pump later. Run your own numbers with our solar system size calculator.
Going fully off-grid is a different project. It requires several days of battery storage on top of the array, and costs depend heavily on the installer and equipment, so get itemized quotes. Most grid-connected homes skip that and use the utility as the battery.
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💰 System Cost
How Much Does a 15–19 kW Solar System Cost in 2026?
Published 2026 residential price figures vary by data source. EnergySage marketplace quotes average about $2.58–$2.75 per watt, while Lawrence Berkeley National Laboratory’s installed-price data puts the cash-purchase median near $3.50 per watt. We use $2.60, $3.00, and $3.50 per watt as a low, midpoint, and high case. Larger systems often price slightly lower per watt.
Estimated gross cost before incentives, 60 kWh/day home
Location
System size
Panels
Cost at $2.60/W
Cost at $3.00/W
Cost at $3.50/W
Phoenix, AZ
11.5 kW
29
≈$29,800
≈$34,400
≈$40,100
U.S. average
15.1 kW
38
≈$39,200
≈$45,200
≈$52,700
Boston, MA
16.0 kW
40
≈$41,500
≈$47,900
≈$55,900
Seattle, WA
19.0 kW
48
≈$49,400
≈$57,000
≈$66,500
Data visualization
Gross cost of a 15.2 kW system by price per watt. The same system costs $39,520 at $2.60/W and $53,200 at $3.50/W before incentives, with no federal credit applied. Source: EnergySage and LBNL figures via NRG Clean Power 2026.
Chart summary: The same 15.2 kW system costs $39,520 at marketplace-quote pricing and $53,200 at the installed-price median, a gap of $13,680. Collecting at least three itemized quotes is the most reliable way to land at the low end.
State and utility incentives still exist and vary widely. DSIRE lists current state rebates, tax exemptions, and net metering rules by address.
Solar vs utility company · 25-year comparison
25-year totals: 3%/yr rate increases, 0.5%/yr degradation, no federal credit. Methodology
Is the Federal Solar Tax Credit Still Available in 2026?
For systems you buy, no. The One Big Beautiful Bill Act, signed July 4, 2025, ended the 30% Residential Clean Energy Credit (Section 25D) for expenditures after December 31, 2025. EnergySage reports that the credit expired for customer-owned systems installed after 2025. Two groups still benefit:
Homeowners with systems finished by December 31, 2025, who can claim the credit and carry forward any unused amount.
Companies that own leased or PPA systems, which can claim the commercial Section 48E credit and may reflect it in your monthly rate. Reporting indicates projects must have begun construction by July 4, 2026, or be placed in service by December 31, 2027.
This guide’s earlier cost figures assumed a 30% credit. Without it, the effective cost of a purchased system is the full gross price. Confirm eligibility with a tax professional, and see our solar tax credit calculator.
⚡ Payback
How Long Is the Solar Payback Period for a 60 kWh/Day Home?
Payback depends mostly on your electricity rate. EIA’s Short-Term Energy Outlook projects an average residential price of 18.2¢/kWh in 2026. At that rate, 21,900 kWh a year costs about $3,990 (roughly $330 a month).
Our reference system is 15.2 kW at the U.S.-average 4.98 peak sun hours. It produces about 22,100 kWh in year one, covering essentially all of 60 kWh/day. At $3.00 per watt it costs $45,600. Simple payback is cost ÷ annual savings, assuming every kWh is credited at your retail rate.
Simple payback by electricity rate (15.2 kW system, $45,600, no federal credit)
Rate basis
Residential rate (¢/kWh)
Annual savings
Simple payback
North Dakota (EIA, Mar 2026)
11.95
≈$2,617
≈17.4 years
Texas (EIA, Mar 2026)
16.39
≈$3,589
≈12.7 years
U.S. average (EIA 2026 forecast)
18.20
≈$3,986
≈11.4 years
Massachusetts (EIA, Mar 2026)
30.21
≈$6,616
≈6.9 years
State rates are from EIA data compiled by Joule. Use the same system for each row so only the electricity rate changes.
Data visualization
Simple payback by state electricity rate. A $45,600 system pays back in about 6.9 years at 30.21 cents per kWh and 17.4 years at 11.95 cents, assuming full retail credit for every kWh. Source: EIA March 2026 state rates and EIA 2026 outlook.
Chart summary: Payback runs from about 7 years at Massachusetts-level rates to more than 17 years at North Dakota-level rates. Rate is the dominant factor, so a high-usage home in a high-rate state gets the strongest return.
The line chart below projects cumulative cash flow over 25 years. It assumes 0.5% annual panel degradation, the median reported in NREL’s degradation research. One scenario holds the rate flat at 18.2¢. The other grows it 2% per year, in line with EIA’s near-term outlook.
Data visualization
25-year cumulative cash flow for a 15.2 kW system. Net savings reach about $49,107 with a flat 18.2 cent rate and $75,131 with 2% annual increases, with no federal credit and 0.5% yearly degradation. Source: EIA 2026 outlook and NREL degradation research.
Chart summary: With a flat rate, the system breaks even in about 11.7 years and nets roughly $49,100 by year 25. If rates rise 2% a year, break-even moves to about 10.6 years and 25-year net savings reach roughly $75,100. The chart leaves out maintenance and inverter replacement, which would reduce both figures. Model your own case with our solar payback calculator.
📋 Key Insights
Does Net Metering Change the Math for a Large System?
Yes. A 15–19 kW array produces more than your home uses at midday, so what your utility pays for exported power shifts the result. The payback figures above assume a credit at or near retail.
California is the clearest example. Its net billing tariff (often called NEM 3.0) cut export credit values by roughly 75–80% versus the previous policy, and a state appeals court upheld it in March 2026. Under low export rates, homes save more by using solar power directly or storing it in a battery for the evening. Rules differ by state and often by utility, so check yours in DSIRE before choosing a system size. See also our net metering calculator and battery storage calculator.
📋 Key Insights
Buy, Finance, or Lease: What Makes Sense After 25D?
The end of the homeowner credit changes the comparison. Weigh total 25-year cost, not just the monthly payment.
Option
Who claims the federal credit
What to compare
Cash purchase
No one (25D ended)
Lowest total cost if you keep the system 25+ years; you keep all savings
Solar loan
No one (25D ended)
Interest rate and fees add to total cost; compare monthly payment with your current bill
Lease or PPA
System owner (48E), may be passed to you in the rate
Escalator clauses, buyout terms, transfer rules if you sell the home
Ask every installer for the 25-year total cost under each option, including any annual rate escalator on a lease or PPA. Because lease and PPA pricing depends on the owner’s credit eligibility and deadlines, confirm in writing that the quote reflects them.
This guide provides general estimates, not a quote, tax advice, or financial advice. Confirm tax treatment with a qualified professional and get written installer quotes.
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About 38 panels rated at 400 W (a 15.2 kW system) at the U.S. average of roughly 5 peak sun hours. Sunnier locations need fewer, around 29 panels in Phoenix. Cloudier ones need more, around 48 panels in Seattle. The formula is daily kWh ÷ peak sun hours ÷ 0.80 system efficiency, then ÷ panel wattage.
A 15.2 kW system costs about $39,500–$53,200 before incentives at $2.60–$3.50 per watt, and a 19 kW system for a cloudy location runs roughly $49,000–$66,000. Marketplace quotes sit near the low end and installed-price medians near the high end. Because the federal 25D credit has ended for purchased systems, those figures are close to what you pay.
Not for systems you buy with cash or a loan. The Residential Clean Energy Credit (Section 25D) ended for expenditures after December 31, 2025 under the One Big Beautiful Bill Act. Companies that own leased or PPA systems can still claim the commercial 48E credit, subject to construction-start and placed-in-service deadlines, and may pass part of the benefit to you.
At the 2026 national average rate of about 18.2¢/kWh, simple payback on a roughly $45,600 system is about 11.4 years. It is near 7 years at Massachusetts-level rates (about 30¢/kWh) and above 17 years at North Dakota-level rates (about 12¢/kWh). Payback is shorter if rates keep rising and longer if your utility pays little for exported power.
Yes. The payback estimates assume your utility credits solar at or near the retail rate. Where export credits are low, as under California's net billing tariff (which cut export values by roughly 75% versus NEM 2.0), savings depend on using solar power yourself or storing it in a battery. Check your utility's current export rate before choosing a system size.
Same usage, bill-based guide
Your 60 kWh/Day target maps to roughly a $300/month electric bill nationally.
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).
Estimates only — not tax, legal or financial advice. Get at least three installer quotes and confirm incentives with your utility and a tax professional.