The average residential solar panel system in the United States costs $2.58 to $3.10 per watt installed in 2026, putting a typical 8-kilowatt rooftop system between $20,000 and $28,000 before any state incentives. The catch: the 30% federal Residential Clean Energy Credit (Section 25D) expired on December 31, 2025 after passage of the One Big Beautiful Bill Act, which means homeowners purchasing systems with cash or a loan in 2026 receive zero federal tax credit. State programs, lease and power purchase agreement (PPA) structures, and rising utility rates now do most of the work that the federal credit used to do.

This guide walks through every variable that determines what you’ll actually pay, from the silver paste inside each cell to the labor costs in your zip code. It covers Tesla’s pricing specifically, breaks down installation costs in Colorado as a representative high-solar state, lays out realistic 25-year ROI by state, and identifies the installers worth getting quotes from.

Solar panel cost 2026: national averages

National pricing data from the EnergySage Marketplace puts the U.S. average at roughly $2.58 per watt installed in 2026, while NuWatt Energy and SolarReviews report a slightly higher average of $2.79 to $3.10 per watt depending on financing structure. The variance comes down to whether you pay cash (lower per-watt cost), use a low-rate loan (modestly higher), or use a dealer-financed solar loan (which typically adds 19–22% to the principal through hidden dealer fees).

According to EnergySage, the average 12 kW solar panel installation costs $30,505 before incentives, with 25-year lifetime savings ranging from $37,000 to $148,000 depending on state and utility. Those savings now have to do all the heavy lifting because there is no longer a federal tax credit shaving 30% off the top.

Why the sticker price hasn’t dropped much since 2019

Hardware has gotten cheaper. According to Lawrence Berkeley National Laboratory’s Tracking the Sun data, panel wholesale prices fell from $0.50 per watt in 2019 to roughly $0.30–$0.35 per watt today. But labor, permitting, and overhead all rose, so the median installed cost moved only slightly — from $2.90/W in 2019 to about $3.10/W in 2026.

That stable gross price is the trap. Because the 30% federal credit was effectively a 30% discount applied at tax time, removing it raises the homeowner’s net cost by about 43% (1 ÷ 0.70 ≈ 1.43) for an identical quote. A 2024 buyer paying $25,000 gross took home a $17,500 net cost. A 2026 buyer paying $25,000 gross pays the full $25,000. Same panels, same roof, $7,500 more out of pocket.

What you’re actually paying for

The panels themselves are the cheapest part. Of every $3.00 per watt you pay an installer, only about 30 to 70 cents goes to the photovoltaic modules. The rest is balance-of-system equipment, labor, and what the industry calls soft costs.

Tesla’s own cost breakdown confirms the labor and overhead reality: installation labor accounts for around 7% of total expenses, while design, engineering, project management, and overhead account for about 28%. Sales and marketing alone can consume up to 18% of the final price at large national installers, which is one reason local installers frequently underbid the household-name brands by 10–25%.

Silver cost in solar panels and why prices haven’t fallen

If you’ve wondered why panel prices stalled out instead of continuing their decade-long decline, look at the silver market. Every solar cell uses a thin layer of silver paste to conduct electricity off the front of the wafer. According to the Silver Institute, photovoltaics consumed roughly 6,577 tons of silver in 2024, accounting for about 19% of global silver demand. Each gigawatt of panels manufactured uses approximately 10 tons of silver.

That demand collided with a supply problem in late 2025. As pv magazine reported, silver hit a record $83.62 per ounce on December 28, 2025, and silver paste alone now represents up to 30% of total solar cell production costs. The same publication noted that module manufacturers have struggled to pass these costs through to end customers, which has compressed margins across the supply chain rather than dramatically raising sticker prices for homeowners.

How the industry is responding

Manufacturers are racing to thrift silver out of cells. Three trends are reshaping the market:

1. Shift to TOPCon and HJT cells: N-type technology used to require nearly double the silver per watt of older Mono PERC cells, but advances in printing and paste formulation have cut that consumption substantially. Per CPIA data cited by pv magazine, HJT silver consumption fell to 75 mg per cell in 2025 — a 35% year-on-year reduction and the lowest of any mainstream n-type technology.
2. Silver-coated copper and pure copper paste: Heterojunction (HJT) leader Risen Energy announced it could cut silver consumption from 6 mg/W to 0.5 mg/W by switching to copper paste. AIKO is pushing 0BB (no-busbar) BC modules with copper electrodes.
3. Domestic Chinese silver powder: Chinese paste manufacturers are substituting domestic ultra-fine silver powder for imported grades to control input costs.

For homeowners, the practical takeaway is simple: don’t expect 2027 panels to be much cheaper than 2026 panels. The historical 10–15% annual price drops are over for now. If your roof is sound, your bill is high, and you can lock in current pricing, waiting for the next big cost decline is a bet against the silver market and tariff policy.

Federal solar tax credit 2026: what survived the OBBBA

The single biggest change to residential solar economics in a decade happened on July 4, 2025, when President Trump signed the One Big Beautiful Bill Act (Public Law 119-21) into law. Among other provisions, it ended Section 25D — the 30% Residential Clean Energy Credit — for systems placed in service after December 31, 2025. There is no phase-down, no partial credit, and no extension. The IRS confirmed in its official guidance that if installation is completed after December 31, 2025, the expenditure is treated as made after that date and the taxpayer cannot claim the Section 25D credit.

For a typical $30,000 residential installation, the expired credit represented $9,000 in direct tax savings. That money is gone for cash buyers and loan buyers in 2026.

What’s still available federally

Three federal pathways remain open:

• Section 48E Clean Electricity Investment Tax Credit: The 30% credit is preserved for businesses that own residential solar systems, including third-party-owned (TPO) leases and PPAs. The leasing company claims the credit and passes the value through as lower monthly payments. The deadline structure is layered: projects whose construction begins by July 4, 2026 qualify for a four-year safe harbor, meaning they can be placed in service as late as roughly mid-2030. Projects whose construction begins after July 4, 2026 must be placed in service by December 31, 2027, to qualify.
• Carryforward of unused 25D credits: Homeowners who installed systems in 2025 but didn’t have enough tax liability to use the full credit can still carry the unused portion forward into 2026 and beyond. According to the Congressional Research Service, the OBBBA did not change the credit’s carryforward rules.
• Modified Accelerated Cost Recovery System (MACRS): Available to commercial entities and TPO providers, allowing faster depreciation of solar assets. Not directly available to homeowners.

FEOC sourcing rules now apply

The OBBBA also introduced Foreign Entity of Concern (FEOC) restrictions for Section 48E projects, including all TPO residential solar. Starting in 2026, at least 40% of the value of manufactured products in the system must come from non-FEOC manufacturers, rising to 45% in 2027 and continuing upward thereafter. These rules don’t apply to homeowner-owned systems (because they’re not claiming any federal credit), but they do affect what equipment your TPO provider can use.

How financing structure changes everything in 2026

Pre-OBBBA, almost every solar advisor recommended cash purchase or a low-rate solar loan because the homeowner captured the full 30% federal credit. That math no longer holds. In 2026, the financing decision actually drives whether you receive any federal incentive at all.

The prepaid TPO lease is the single biggest change in 2026 buyer behavior. It works like this: you pay roughly 70% of the cash purchase price upfront, the leasing company owns the system for the term (typically 6 years before ownership transfer or 20–25 years for full term), claims the 30% Section 48E credit, and passes that value through to you in the discounted price. The window for new TPO contracts to capture full federal credit value runs through the safe-harbor deadline of July 4, 2026; after that, leasing companies can still pass through value on projects they’ve already started, but the economics tighten quickly.

Tesla solar panels cost 2026

Tesla remains one of the lowest-priced national installers, but its pricing has crept up since 2024. Tesla’s own cost guide cites U.S. Department of Energy figures showing an all-in cost between $2.74 and $3.30 per watt for residential solar systems. In practice, Tesla quotes in 2026 typically land between $2.50 and $3.00 per watt for cash purchases, with regional variation: California buyers see closer to $2.50/W while New Jersey and parts of the Northeast see quotes near $3.00–$3.10/W.

What you get with Tesla

Tesla’s standard 2026 panel is an all-black module in the 400–425 W range (verify the exact wattage on your quote), with a low-profile, rail-less mounting system. Pairing solar with a Powerwall 3 adds approximately $11,500 to $13,500 for the battery and inverter package. Tesla’s price-match policy lets you submit competing quotes within 14 days of receiving Tesla’s quote, and the company historically honors matches for comparable equipment specifications.

Tesla Solar Roof: a separate calculation

The Tesla Solar Roof — glass tiles that replace your existing roof — costs $5.00 to $7.00 per watt, or roughly $40,000 to $90,000 for an 8 kW equivalent system depending on roof complexity. It only makes financial sense if you genuinely need a new roof; comparing it to standard panels on an existing roof is comparing the wrong things.

Where Tesla falls short

Multiple installer rankings — including EcoWatch’s 2026 review, customer feedback aggregated on SolarReviews, and persistent BBB complaint volume — place Tesla outside the top tier on customer service. The company outsources much of its installation to third-party contractors and has faced lawsuits over defective installations. Tesla’s loan APRs have run in the high single digits in recent quarters, often higher than what local installers can offer through credit-union solar loan programs in many markets. The hardware is good; the post-install support is the weak link. Confirm the current loan APR on your specific quote — Tesla updates these in line with broader interest-rate movements.

Colorado solar panel installation cost 2026

Colorado is one of the better solar markets in the country thanks to 300+ sunny days a year, no state sales tax on solar equipment, and Xcel Energy’s net metering at retail rate. Statewide, the average installed cost is $2.72 per watt in 2026 according to EnergySage’s April 2026 marketplace data, slightly above the $2.58 national average but well below high-cost northeastern states.

One thing to expect on a Colorado quote: the typical system is meaningfully larger than the U.S. median. Where the national median home runs about 10,500 kWh/yr and a 8 kW system handles it, the average Colorado installation is closer to 11 kW. Cold winters, electric resistance and heat-pump heating loads, and a rising share of EV charging push consumption up; installers size accordingly.

Colorado-specific incentives that still work in 2026

• State sales tax exemption: Solar equipment is fully exempt from Colorado’s 2.9% state sales tax under CRS §39-26-724, saving roughly $700–$900 on a typical $30,000 system.
• Property tax exemption: Residential solar systems do not increase your property’s assessed value for tax purposes (CRS §39-3-118.5), preserving thousands in long-term savings.
• Xcel Energy Solar*Rewards: Performance-based incentive payments for the first 10 years; the per-kWh rate is set annually by program year and capacity tier, so confirm the current rate on Xcel’s program page before signing.
• Black Hills Energy Renewable Ready: Available in southern Colorado service territory, offers upfront rebates for qualifying systems up to 10 kW.
• Local utility rebates: Holy Cross Energy, La Plata Electric, and several rural co-ops offer rebates ranging from $500 to $2,000.
• Net metering at retail rate: Investor-owned utilities (Xcel, Black Hills) credit excess generation at full retail rate, banked monthly and trued up annually.

According to EnergySage’s Colorado data, the average Colorado homeowner saves about $33,204 over 25 years by installing solar, even without any federal tax credit. With Xcel territory rebates layered on, that figure pushes above $40,000 in the strongest cases.

Solar panel maintenance costs 2026

Solar maintenance is one of the few expenses in homeownership that has stayed boring and predictable. Most homeowners spend $300 to $850 per year on routine upkeep, plus one significant inverter replacement at the 10-to-15-year mark. Over a 25-year system life, total maintenance typically runs 1–2% of the original installation cost annually.

What actually breaks

According to Angi’s 2026 maintenance data, the inverter is by far the most common point of failure in residential solar. Solar contractor Vincent Curcie, quoted in Angi’s report, said issues with the solar inverter are the most common problem encountered with a solar panel system. Panels themselves are remarkably durable — most carry 25-year performance warranties guaranteeing 80–87% of rated output at year 25.

Cleaning: when it actually matters

In rainy regions of the Pacific Northwest, the Northeast, and the Southeast, natural rainfall handles most of the cleaning. In arid regions (Arizona, Nevada, inland California, Colorado’s Front Range during dry stretches), dust and pollen can cut output by 5–25% if panels go uncleaned for a year or more. Tesla’s documentation notes that cleaning with soapy water and a non-abrasive sponge can improve energy production by 3–5%, though many homeowners safely skip professional cleaning entirely if their system is in a wet climate and accessible to natural rinsing.

What homeowner’s insurance does and doesn’t cover

Most standard homeowner’s policies in 2026 cover roof-mounted solar panels as part of the dwelling structure, including damage from storms, hail, falling trees, and fire. Ground-mounted arrays may require a rider. Insurance does not cover normal wear, manufacturer defects (those go to your panel warranty), or inverter failure outside warranty. Confirm coverage in writing before installation; your premium will typically rise $50–$100 per year to reflect the added insured value.

Solar panel ROI by state

State-level economics now determine whether your solar investment is excellent, mediocre, or marginal. With the federal credit gone, three variables matter most: your local electricity rate, your state’s net metering policy, and any state-level rebates or SREC market. The average U.S. solar payback period sits at 8.7 years in 2026, but the spread runs from under 6 years in the best states to over 14 years in the worst.

According to Green Energy Calculators’ 2026 state-by-state analysis citing EIA Q1 2026 data, the four factors that move payback periods most are electricity rate (single biggest driver), peak sun hours, state incentives, and net metering policy. Hawaii residents pay roughly four times what Louisiana residents pay per kWh, and that difference alone explains why solar pays back in 5 years in Honolulu and 14 years in Baton Rouge.

The net metering wildcard

California’s transition from NEM 2.0 to NEM 3.0 (the Net Billing Tariff) cut solar export rates by roughly 75% for new systems and lengthened payback by 2–4 years for solar-only installations. The workaround: pair panels with a battery that stores midday production for evening use, so you avoid both buying expensive peak power and selling cheap midday power. NEM 3.0 economics work, but only when the system is sized for self-consumption rather than oversized for export credits.

Other states to watch: Arizona ended full retail net metering years ago, Indiana’s grandfathered customers largely lost full retail status by 2022, and Florida has flirted repeatedly with cuts that have so far been blocked. If your state’s net metering rules are stable in 2026, that’s a meaningful asset.

Best solar installers in 2026

The right installer matters more than the panel brand. Tier-1 monocrystalline panels from Hanwha QCells, JinkoSolar, LONGi, REC, Maxeon, Panasonic, and Canadian Solar are all functionally similar in real-world output. What differs is design quality, install crew skill, warranty enforcement, and post-install support. Here’s how the major options compare in 2026.

National installers worth quoting

• Sunrun: Largest U.S. residential solar company and consistently ranked at or near the top of national installer reviews (ConsumerAffairs, SolarReviews, and EcoWatch all list it among the top tier for 2026). Strong on lease and PPA financing — which preserves access to the 30% Section 48E credit pass-through. Available in 22 states plus DC and Puerto Rico. Customer service is mid-tier; pricing is competitive but rarely the lowest.
• Tesla: Lowest-priced national option, particularly strong if you want Powerwall integration. Customer service consistently rates below average across major review aggregators; expect to be your own project manager for any post-install issue. Best for cost-focused buyers who can self-advocate.
• Freedom Forever / Freedom Power Solar: Large national footprint with flexible financing options including $0-down loans. Performance varies meaningfully by regional dealer, so check local reviews before signing.
• Project Solar: DIY-assist model — they handle design, permits, and equipment procurement, you (or a local contractor you hire) handle install. Significantly lower per-watt cost ($1.99–$2.30/W in many markets) but requires comfort coordinating subcontractors.
• Palmetto Solar: Software-driven national installer with strong design transparency. Operates through certified local installer partners, which gives you national support with local execution.

Why local installers usually beat national brands on price

Sales and marketing alone can be 18% of a national installer’s price. A local installer with a five-truck operation and zero TV ad budget can offer the same equipment for $0.30–$0.50 less per watt. NABCEP (North American Board of Certified Energy Practitioners) certification is the gold standard regardless of company size — its PV Installation Professional credential requires both documented field experience on a meaningful number of installs and passing a rigorous technical exam, plus adherence to a code of ethics. A NABCEP-certified installer on a small local crew is a stronger signal than a national brand without one.

What to demand in every quote

1. $/W stated explicitly, not just total dollar figure. This is the only fair way to compare bids.
2. Production estimate in kWh per year, with the modeling tool named (Aurora, HelioScope, Genability, or PVWatts).
3. Equipment specifics: panel make/model, inverter make/model, racking system, and monitoring platform.
4. Three separate warranties: panel performance (25 years), panel product (12–25 years), and workmanship/labor (10+ years is the bar).
5. Roof penetration warranty from the installer (separate from the panel warranty), ideally 10 years against leaks.
6. Itemized quote showing the dealer fee if any. A loan with no dealer fee at 7.5% is often cheaper than a loan with a 22% dealer fee at 5.99%.
7. Permit and interconnection fees specified, not buried in soft costs.

Get at least three quotes. The cheapest is rarely the best, but the most expensive is almost never worth it.

Solar scams and red flags to avoid

The solar industry attracts a disproportionate number of high-pressure sales operations, and the loss of the federal tax credit has made some bad actors more aggressive in 2026 as they try to close deals before homeowners do the new math. Here are the warning signs that should end the conversation immediately.

• “This federal program ends tomorrow” claims: The Section 25D residential credit already expired. Anyone telling you to sign today to lock in the federal tax credit on a homeowner-owned system in 2026 is either misinformed or lying.
• Door-to-door sales without leaving documents: Reputable installers send written quotes you can review for days. A salesperson who refuses to leave the contract for you to study elsewhere is hiding something.
• Quotes presented only as monthly payments: A $159/month payment can hide a $48,000 loan with $11,000 in dealer fees on a system worth $25,000. Always demand the total system cost, dealer fee, APR, and term.
• “Free solar” or “the government pays for it”: Solar is not free. PPAs and leases shift cost to a per-kWh bill, and government incentives reduce — not eliminate — your cost. Anyone using these phrases is misrepresenting the deal.
• Estimates without a site assessment: Real production estimates require satellite imagery analysis at minimum, ideally a roof inspection. A quote based purely on your zip code and bill is marketing, not engineering.
• Pressure to sign the same day: Legitimate solar projects take 2–6 months from contract to commissioning. There is no operational reason to sign immediately. Walking away rarely costs you the deal.
• UCC-1 filings on your home: Some leasing companies file Uniform Commercial Code liens against the home, not just the solar equipment. This complicates resale and refinancing. Demand language that limits any lien to the equipment itself.

Verify the company on the Better Business Bureau, your state contractor license board, and SolarReviews. A company that has been in business for fewer than three years, has unresolved BBB complaints, or is not properly licensed in your state should be excluded from your shortlist regardless of the quote.

Is solar still worth it in 2026?

For most U.S. homeowners with a $120-or-higher monthly electric bill, a sound roof, and at least 4 hours of unshaded peak sun, the answer is still yes — but the case is narrower than it was in 2024. Here’s the honest breakdown.

The argument for solar in 2026

• Electricity rates rose 5.4% nationally in the year ending April 2026 per EIA data, and 21% over the past five years. Every kWh you self-generate locks in protection from future hikes.
• Solar adds approximately $4,000 per kilowatt to home value per Lawrence Berkeley National Laboratory and Zillow research, which means an 8 kW system adds about $32,000 to resale price in solar-heavy markets.
• State incentives still work, and several states (NY, MA, NJ, RI, MD) have actually expanded programs in 2026 to partially offset the federal credit loss.
• Levelized cost of solar electricity is 6–8 cents per kWh for systems purchased through competitive marketplaces, well below the 17 cent national grid average.
• Time-of-use rates are spreading, which makes solar plus battery substantially more valuable than solar alone.

The argument against

• Payback periods are 3–4 years longer without the federal credit, pushing some marginal markets (Louisiana, Kentucky, parts of the Mountain West) into questionable ROI territory.
• If you plan to move within 5 years, the math rarely works on a cash purchase. A lease may transfer to the next owner more easily.
• Roof age matters. If your roof has fewer than 10 years of service life left, replace it first. Removing and reinstalling panels later costs $2,000–$5,000.
• If your home is heavily shaded or oriented poorly (north-facing primary roof in the Northern Hemisphere), the production hit may not justify the cost.

The realistic 2026 decision framework

Run three numbers before you sign anything: your current monthly electric bill, the total quoted system cost minus all available state and utility incentives, and your honest expected years in the home. If your bill is over $150, your net cost is under $25,000, and you’re staying at least 8 years, the financial case is strong in nearly every state. If two of those three don’t pencil, either look at a prepaid TPO lease (which captures the residual federal incentive value) or wait until your situation aligns better.

Frequently asked questions

What is the average cost of solar panels in 2026?

National average is $2.58 to $3.10 per watt installed, putting a typical 8 kW system between $20,000 and $28,000 before incentives. Pricing varies by state from about $2.20/W in Texas to $3.18/W in New Hampshire.

Did the federal solar tax credit go away in 2026?

Yes. The 30% Residential Clean Energy Credit (Section 25D) expired on December 31, 2025, after the One Big Beautiful Bill Act eliminated it nearly a decade ahead of its scheduled 2034 expiration. Homeowners who buy solar with cash or a loan in 2026 receive zero federal credit.

Can I still get any federal incentive for residential solar?

Yes, but only through a third-party-owned system. Solar leases and PPAs still qualify for the 30% Section 48E commercial Investment Tax Credit. Projects whose construction begins by July 4, 2026, get a four-year safe harbor on the placed-in-service date; projects starting after July 4, 2026, must be placed in service by December 31, 2027. The leasing company claims the credit and passes the value through as lower monthly payments.

How much do Tesla solar panels cost in 2026?

Tesla quotes typically range from $2.50 to $3.10 per watt installed in 2026. A standard 8.4 kW system runs $21,000 to $25,500 before any state incentives. The Tesla Solar Roof costs significantly more at $5.00 to $7.00 per watt, only making sense for homeowners who need a full roof replacement anyway.

How much does solar cost in Colorado in 2026?

The Colorado statewide average is $2.72 per watt installed. A typical 11 kW system costs about $29,833 before incentives. Denver runs slightly cheaper at $2.68/W, while smaller markets and the Western Slope can be closer to $2.90/W.

Why hasn’t the price of solar panels dropped more in 2026?

Module hardware did get cheaper, but silver paste prices spiked to a record $83.62 per ounce in late 2025, accounting for up to 30% of cell production cost. Combined with rising labor, permitting, and overhead, the all-in installed price has only declined modestly since 2019, even before factoring in the loss of the federal credit.

How much will I spend on solar maintenance per year?

Most homeowners spend $300 to $850 per year, including occasional cleaning ($150–$330) and an annual professional inspection ($150–$300). Plan for one inverter replacement around year 10–15 at $1,000–$2,500 for a string inverter or $150–$350 per microinverter unit.

How long does it take for solar panels to pay for themselves?

The U.S. average payback in 2026 is 8.7 years, with significant state variation. Hawaii pays back in 4–6 years, the Northeast (NJ, MA, NY, RI) in 6–8 years, the Mountain West and Sun Belt in 9–12 years, and low-rate states like Louisiana in 13–14 years.

Do solar panels increase home value?

Yes, by approximately $4,000 per kilowatt installed for owned systems, per Lawrence Berkeley National Laboratory and Zillow research. Leased systems generally do not increase home value and can complicate resale because the lease must be transferred or bought out.

Should I add a battery to my solar system in 2026?

Add a battery if your state has weak net metering (CA NEM 3.0, AZ, NV), if you have time-of-use rates with high evening prices, or if grid reliability is a concern. Skip the battery if you have full retail net metering and a stable grid; the $11,500–$15,000 added cost usually doesn’t pay back through arbitrage alone in those markets.

What’s the best solar panel brand for 2026?

For maximum efficiency in tight roof space, Maxeon (the panels formerly sold under the SunPower brand) and REC Alpha Pure-R lead. For best value, Hanwha QCells, JinkoSolar Tiger Neo, and LONGi Hi-MO 6 deliver excellent performance at lower cost. Tier-1 monocrystalline panels from any of these brands will perform comparably for 25+ years.

How many solar panels do I need for my home?

The average U.S. home uses about 10,500 kWh/yr and needs 18 to 25 panels (depending on wattage) to offset 100% of usage in a sunny climate. In cloudier regions or with heavy shading, you’ll need 25 to 32 panels. Use your last 12 months of utility bills as the starting point.

Is it true SunPower went out of business?

SunPower Corporation, the residential solar installer, filed for Chapter 11 bankruptcy on August 5, 2024, and ceased new installations. Some assets were sold to Complete Solaria. The high-efficiency panels are still manufactured by Maxeon Solar Technologies, a separate publicly traded company that spun off from SunPower in August 2020. If you owned a SunPower-installed system, your panel warranty is held by Maxeon; your workmanship warranty depends on which company assumed the service contracts in your region.

Glossary of solar terms

Cost per watt ($/W)

The total installed system cost divided by total wattage, used as the standard apples-to-apples comparison metric across solar quotes regardless of system size.

FEOC (Foreign Entity of Concern)

A category of foreign manufacturers (primarily Chinese, Russian, North Korean, and Iranian) restricted under the OBBBA. As of 2026, Section 48E projects must source at least 40% of equipment value from non-FEOC manufacturers, rising annually thereafter. Treasury and IRS guidance on FEOC and “material assistance” definitions continues to evolve, so the exact thresholds may shift between now and 2027.

HJT (Heterojunction)

A high-efficiency solar cell technology that uses thin layers of amorphous and crystalline silicon. HJT cells require less silver per watt than competing TOPCon cells when silver prices exceed roughly $40 per ounce.

ITC (Investment Tax Credit)

The federal tax credit applied to renewable energy investments. Section 25D applied to homeowner-owned residential systems (expired end of 2025); Section 48E applies to business-owned systems including residential leases and PPAs (still active under the safe-harbor and placed-in-service rules described in the federal tax credit section above).

kWh (kilowatt-hour)

The unit of electrical energy your utility bills you in. A 1 kW appliance running for 1 hour uses 1 kWh. The U.S. residential average is roughly 10,500 kWh consumed per year.

Microinverter

A small inverter installed at each individual panel, in contrast to a single string inverter for the whole array. More expensive but handles partial shading better and allows panel-level monitoring.

NABCEP

The North American Board of Certified Energy Practitioners, the leading independent certification body for solar professionals. Its PV Installation Professional credential is the industry’s most respected certification and requires significant documented field experience in addition to passing a technical exam.

Net metering

A utility billing arrangement that credits solar customers for excess electricity exported to the grid, typically at retail rate. Some states have shifted to lower export rates (e.g., California’s NEM 3.0).

OBBBA (One Big Beautiful Bill Act)

Public Law 119-21, signed July 4, 2025. The legislation that ended the Section 25D residential solar tax credit and Section 25C energy efficiency credit at the end of 2025, while preserving Section 48E commercial credits with safe-harbor and placed-in-service deadlines through 2027.

PPA (Power Purchase Agreement)

A financing structure where a third party owns and maintains the solar system on your roof and you buy the electricity it produces at a fixed per-kWh rate. The third party claims the federal tax credit.

Soft costs

Non-hardware expenses including sales, marketing, permits, design, engineering, financing, labor, and installer overhead. Soft costs typically represent 50–65% of the total installed price of a U.S. residential solar system.

SREC (Solar Renewable Energy Certificate)

A tradable certificate representing the environmental attributes of one megawatt-hour of solar generation. Some states (NJ, MA, MD, DC) maintain markets where homeowners can sell SRECs for $50–$300 each.

TOPCon (Tunnel Oxide Passivated Contact)

The dominant high-efficiency solar cell architecture in 2026, offering ~22–23% efficiency at moderate cost. Most major Tier-1 manufacturers ship TOPCon as their mainstream product.

TPO (Third-Party Ownership)

Any financing structure where a company other than the homeowner owns the solar equipment, including leases and PPAs. TPO is the only path to federal tax credit value for residential solar in 2026.