Calculator
Solar savings & payback calculator.
Estimate what solar would cost and save where you live. Pick your state and city to load defaults from public data: your utility's average price and usage from EIA, solar output from PVWatts, the state's median installed price from Berkeley Lab, and your utility's export rules. Then replace them with the numbers on your bill and your quotes. Nothing you type is sent anywhere.
Calculator
Pays for itself in
14.9
years to break even
A 7.4 kW system in Arizona costs about $22,940 ($21,940 after incentives), saves about $1,337 in its first year and pays for itself in about 14.9 years.
Month by month
Solar output vs. your use
Cash position
When you break even
Year one
Where the savings come from
- Used at home
- +$997
- Export credits
- +$361
- Solar charges & upkeep
- −$21
- Year-one savings
- $1,337
25 years
Bills with and without solar
Over 25 years you keep $17,914 compared with not going solar.
Where the defaults come from [ 5 sources ]
- PriceArizona average residential price, Jan–Aug 2026 average (preliminary) · source
- UseLocal residential average · source
- OutputPVWatts estimate for Phoenix · source
- CostState median, an estimate · source
- ExportsAPS credits exports at 5.55¢ per kWh (Rate Rider RCP (Resource Comparison Proxy export rate)). Solar customers also pay $0.24 per kW of panels a month, included in the estimates. · source
How the calculator works
The calculator sizes a system to cover the share of your yearly electricity use you choose, multiplies its size by your price per watt, subtracts the incentives you select, and then adds up savings year by year. Each year, output falls slightly as panels age and the electricity price rises by the rate you set. Energy you use as it is produced saves the full retail price; exported energy earns your utility's export credit, or offsets purchases at retail where your utility still offers net metering. Payback is the point where cumulative savings first reach your net cost. The methodology page lists every formula and default.
How to get an accurate answer
- Use your real usage. Add up the kWh on your last twelve bills and divide by twelve.
- Use your quote's price per watt and size. Tick "I have a quote with a system size".
- Set the share used at home. Under net billing this matters most. Homes that are empty during the day use less of their solar directly; a battery or daytime EV charging raises the share.
- Check your utility's export rate on our net metering pages and enter your retail plan's buyback rate if you live in Houston or Dallas.
- Compare financing honestly. Choose "Loan" and enter the APR with fees; the calculator shows total interest next to your savings.
FAQ
Frequently asked questions
How accurate is a solar calculator?
It is as accurate as its inputs. With your own usage, your quote's size and price, and your utility's export rate, the estimate is a sound planning number; roof direction, shading and rate-plan changes can still move the result.
Why does the calculator not include the federal tax credit?
Because homeowners who buy a system installed after December 31, 2025 cannot claim it. See the Federal Residential Clean Energy Credit (25D)[1].
Do you collect my information?
No. The calculator runs entirely in your browser, needs no sign-up and sends nothing to us or to installers.
sources
[ 56 ]Every number on this page links to one of these sources. Dates show when we last checked each one.
- IRS FS-2025-05: FAQs for modification of sections 25C, 25D, 25E, 30C, 30D, 45L, 45W, and 179D under Public Law 119-21 (OBBB)irs.gov · checked Nov 5, 2026
- EIA Electric Power Monthly, Table 5.6.B: Average price of electricity by state, year-to-date (August 2026, preliminary)eia.gov · checked Nov 5, 2026
- EIA Electric Sales, Revenue, and Average Price 2024, Table 5A: Residential average monthly bill by stateeia.gov · checked Nov 5, 2026
- NREL/NLR PVWatts v8 (1 kW-DC, fixed roof mount, 20° tilt, south-facing, 14% losses, TMY weather)pvwatts.nlr.gov · checked Nov 5, 2026
- U.S. Distributed Solar and Storage 2026 Data Update (Barbose, Darghouth, O'Shaughnessy, Forrester), Berkeley Labeta-publications.lbl.gov · checked Nov 5, 2026
- Alabama Power - Rate PAE, Purchase of Alternate Energy (Forty-Seventh Revision, April 2026 Billings)alabamapower.com · checked Nov 5, 2026
- Chugach Electric - North District rates (Purchased Power Rates for Qualified Facilities)chugachelectric.com · checked Nov 5, 2026
- APS: Rate Rider RCP (Resource Comparison Proxy export rate)aps.com · checked Nov 5, 2026
- Entergy Arkansas Rate Schedule No. 71, Non-Legacy Net-Metering Service (NLN-M), Attachment A Avoided Cost Rate (effective 3/2/26)entergyarkansas.com · checked Nov 5, 2026
- PG&E: Solar Billing Plan (Net Billing Tariff, 'NEM 3.0')pge.com · checked Nov 5, 2026
- Xcel Energy Colorado Solar Bank Election Form (17-9178, 02-24)xcelenergy.com · checked Nov 5, 2026
- Residential Renewable Energy Solutions - Program Manual, Version 2026.1 (Eversource/UI)eversource.com · checked Nov 5, 2026
- 26 DE Admin. Code 3001 - Final Order No. 10430 (27 DE Reg 983, June 2024)archive.regulations.delaware.gov · checked Nov 5, 2026
- Pepco compliance filing for Standard Offer Service retail rates, Formal Case No. 1017 (May 27, 2026), Rider SOS - Schedule Redocket.dcpsc.org · checked Nov 5, 2026
- FPL: FPL net metering under Rule 25-6.065 (Tier 1/2/3 Interconnection Agreements, tariff sheets 9.050-9.065)fpl.com · checked Nov 5, 2026
- Georgia Power - Rooftop Solar FAQs (with RNR-11 tariff, effective January 2023 billing month)georgiapower.com · checked Nov 5, 2026
- Hawaiian Electric Rule No. 32 Smart Renewable Energy Program, Export Rider, Sheet No. 49.40-Hhawaiianelectric.com · checked Nov 5, 2026
- Idaho PUC news release, Case No. IPC-E-25-15 Order No. 36785 (Oct 2, 2025)puc.idaho.gov · checked Nov 5, 2026
- Plug In Illinois (ICC) - Price to Compare - ComEdplugin.illinois.gov · checked Nov 5, 2026
- AES Indiana Standard Contract Rider No. 16 Excess Distributed Generation (EDG), Effective July 27, 2026aesindiana.com · checked Nov 5, 2026
- Customer Interconnection and Rates Information - MidAmerican Energy (read via web.archive.org snapshot of June 14, 2026; live site refused connection)midamericanenergy.com · checked Nov 5, 2026
- K.S.A. 66-1266 Interconnection agreements; billing of customer-generators; credit for exports of excess electricity (as amended L. 2024, ch. 60)ksrevisor.gov · checked Nov 5, 2026
- Kentucky PSC Order (nunc pro tunc), Case No. 2025-00113, Kentucky Utilities Company rate case (Mar 4, 2026)psc.ky.gov · checked Nov 5, 2026
- Entergy Louisiana, LLC Schedule DG - Optional Residential/Commercial Distributed Generation Rider, incl. Attachment A (eff. 4/1/2026)entergylouisiana.com · checked Nov 5, 2026
- Central Maine Power - Frequently Asked Net Energy Billing Questions (read via Wayback Machine copy of 15 Jul 2026)cmpco.com · checked Nov 5, 2026
- Maryland Code, Public Utilities 7-306mgaleg.maryland.gov · checked Nov 5, 2026
- Net metering guide | Mass.govmass.gov · checked Nov 5, 2026
- DTE Energy letter to Rooftop Solar Customers - Distributed Generation Rider 18 (PA 235)dteenergy.com · checked Nov 5, 2026
- Minn. Stat. 216B.164 - Cogeneration and Small Power Productionrevisor.mn.gov · checked Nov 5, 2026
- Entergy Mississippi, LLC Net Energy Metering Rate Schedule NEM-2 (P.S.C. Schedule No. I-27.20) with Attachment Aentergymississippi.com · checked Nov 5, 2026
- Ameren Missouri - Residential Solar (read via Wayback Machine copy of 7 Aug 2025; live site returns HTTP 403 to automated requests)ameren.com · checked Nov 5, 2026
- Montana Code Annotated 2025, 69-8-603 Net energy measurement calculationmca.legmt.gov · checked Nov 5, 2026
- Nebraska Public Power District Net Metering Service Rider Rate Schedule (NM-RIDER), effective January 1, 2026 (linked from nppd.com/rates/net-metering)cdn.prod.website-files.com · checked Nov 5, 2026
- Nevada Power Company d/b/a NV Energy Electric Rate Schedules for Residential and General Service Customer Generation (effective July 1, 2026)nvenergy.com · checked Nov 5, 2026
- New Hampshire Net Metering - Eversourceeversource.com · checked Nov 5, 2026
- Net Metering and Interconnection - New Jersey's Clean Energy Program (NJ BPU)cleanenergy.nj.gov · checked Nov 5, 2026
- 17.9.570 NMAC - Governing Cogeneration and Small Power Production (NM State Records Center and Archives)srca.nm.gov · checked Nov 5, 2026
- Con Edison: Phase One NEM (Rider R) with Customer Benefit Contributionconed.com · checked Nov 5, 2026
- Net Metering | NC Public Staff - Utilities Commissionpublicstaff.nc.gov · checked Nov 5, 2026
- Montana-Dakota Utilities - Renewable / Solar Energy (read via Wayback Machine copy of 10 Oct 2026; live site returns HTTP 403 to automated requests)montana-dakota.com · checked Nov 5, 2026
- AEP Ohio Tariff Book (September 2026), Generation Energy Rider Sheet 450-1 and Net Energy Metering Serviceaepohio.com · checked Nov 5, 2026
- Net Metering in Oklahoma - Oklahoma Corporation Commissionoklahoma.gov · checked Nov 5, 2026
- ORS Chapter 757 (757.300 Net metering facilities) - Oregon Legislatureoregonlegislature.gov · checked Nov 5, 2026
- Alternative Energy Portfolio Standards Act, Act of Nov. 30, 2004, P.L. 1672, No. 213, Section 5 (as amended by Act 35 of 2007) - Pennsylvania General Assemblypalegis.us · checked Nov 5, 2026
- R.I. Gen. Laws § 39-26.4-2(8) (as amended by P.L. 2025, ch. 256 and ch. 269, effective June 27, 2025), read via web.archive.org snapshot of 2026-10-14 (rilegislature.gov refuses direct fetches)webserver.rilegislature.gov · checked Nov 5, 2026
- South Carolina Code of Laws, Title 58 Chapter 40 (Section 58-40-20)scstatehouse.gov · checked Nov 5, 2026
- Northern States Power Co. South Dakota Electric Rate Book SDPUC No. 2, Section 9, Sheet 2 - Occasional Delivery Energy Service, Rate Code E50 (effective 01-01-26)puc.sd.gov · checked Nov 5, 2026
- TVA EnergyRight - July 2026 Dispersed Power Production (DPP) Guidelines, Attachment A price scheduleenergyright.com · checked Nov 5, 2026
- CPS Energy: Monthly net billing with Net Excess Generation (NEG) creditcpsenergy.com · checked Nov 5, 2026
- Utah PSC letter approving Rocky Mountain Power Schedule 137 revisions, Docket 26-035-T03 (Feb. 23, 2026)pscdocs.utah.gov · checked Nov 5, 2026
- Green Mountain Power Tariff v. V.P.U.C. 10 - Self Generation and Net Metering (effective with bills rendered on or after October 1, 2026)static.greenmountainpower.com · checked Nov 5, 2026
- Code of Virginia § 56-594 - Net energy metering provisionslaw.lis.virginia.gov · checked Nov 5, 2026
- RCW 80.60.030 - Net energy measurement, charges for kilowatt-hour consumption, and credits for excess kilowatt-hour generationapp.leg.wa.gov · checked Nov 5, 2026
- FirstEnergy - Mon Power and Potomac Edison Reach Settlement to Adjust Energy Metering Creditsfirstenergycorp.com · checked Nov 5, 2026
- We Energies - 2026 Customer Generation Rates brochure (PSCW-authorized CGS rates)we-energies.com · checked Nov 5, 2026
- Wyoming Legislature - 2025 Bill Digest HB0183 Net metering amendmentswyoleg.gov · checked Nov 5, 2026