Residential Solar Frequently Asked Questions

Solar return on investment (ROI) is calculated by dividing your total system cost by your estimated annual energy savings. Annual savings are determined by multiplying system output — calculated as System kW × Daily Sun Hours × 365 × 0.75 efficiency factor — by your local electricity rate. Our free ROI Calculator handles this automatically once you enter your system size, cost, and electricity rate.

Most homeowners can expect a payback period of 6–12 years, though this varies widely by location, electricity rate, system size, and installation cost. States with higher electricity rates tend to see faster payback. New Jersey and Massachusetts regularly see payback periods of 5–7 years. After payback, most systems continue producing free energy for 15–25 additional years. Use our Solar ROI Calculator to estimate your specific payback period.

A typical residential solar installation costs between $15,000 and $25,000 before incentives, or roughly $2.50 to $3.50 per watt installed. A 6 kilowatt (kW) system — enough for an average US home — runs about $15,000 to $21,000. Prices have fallen roughly 90% since 2010 and continue to decrease. State tax credits, utility rebates, and sales tax exemptions can reduce your out-of-pocket cost significantly depending on where you live. See our Solar Tax Credits 2026 guide for current incentives by state.

System size should be driven by your annual electricity usage, not your roof size or number of panels. The basic formula: divide your annual kilowatt-hour (kWh) usage by your location's peak sun hours per day multiplied by 365. Most US homes use around 10,500 kWh per year and need a 6–10 kW system. Add about 20% to account for real-world efficiency losses. See our full guide: How Much Solar Do I Need? Sizing Your System the Right Way.

The federal 30% residential solar tax credit expired December 31, 2025 under the One Big Beautiful Bill Act. State-level programs are now the primary incentives. New York offers a 25% state credit up to $5,000; Massachusetts 15% up to $1,000; South Carolina 25% up to $3,500 per year; and Hawaii 35% up to $5,000. Most states also offer property tax exemptions and sales tax exemptions for solar equipment. For a full breakdown by incentive type, see our Solar Tax Credits Explained: What Homeowners Can Claim in 2026. For a state-by-state breakdown of what's available where you live, see our Solar by State guides.

Yes, through net metering programs available in about 38 states plus Washington D.C. When your panels produce more than you use, the excess flows to the grid and your utility credits your electricity bill — reducing what you owe rather than sending you a check. Credit rates vary significantly: New Jersey and Massachusetts offer full retail credit (around 26–30 cents per kWh), while California's Net Energy Metering 3.0 (NEM 3.0) reduced rates to just 5–8 cents per kWh. Texas has no statewide net metering at all. For a full state-by-state guide, see Net Metering 101: How to Get Paid for Your Excess Solar Energy. For your specific state's rules, see our Solar by State guides.

When you buy (with cash or a loan), you own the system. You keep all electricity savings, claim any available state tax credits, and benefit from the full increase in home resale value. Buying delivers the best long-term return but requires upfront capital or financing.

When you lease or sign a Power Purchase Agreement (PPA), a solar company owns the system. You pay a fixed monthly fee or a per-kWh rate that's typically lower than your current utility rate. There's little or no upfront cost, but you don't own the panels, can't claim state tax credits directly, and the resale value benefit is smaller or more complicated to transfer.

One important 2026 note: the commercial solar tax credit (which applies to company-owned systems) still runs through 2027. Leasing companies can claim this credit and often pass some savings to customers through lower monthly rates — so leasing pricing may be more competitive than it first appears. See our tax credits guide for more detail on this.

Yes. Roof orientation, pitch, and material all affect output. South-facing roofs with a 15–40° pitch typically achieve maximum production. Shading from trees or chimneys can significantly reduce output, and roofs in poor condition may need replacement before installation. Most professional installers provide a free site assessment. Our pre-installation checklist covers the six key areas to evaluate before talking to any installer.

Peak sun hours represent the number of hours per day when sunlight intensity averages 1,000 watts per square meter — not simply daylight hours. In the US, this ranges from about 3.5 hours per day in New England to over 6.5 hours per day in parts of the Southwest. Our ROI Calculator and Quick Savings Estimate both pre-fill state-level averages automatically. For a state-by-state comparison, see our Best States for Solar in 2026 guide.

Standard grid-tied solar systems automatically shut down during power outages as a safety requirement to protect utility workers on the lines. Your panels may be producing power in bright sunshine, but none of it reaches your home while the grid is down. If backup power during outages is a priority, you need a battery storage system. Battery-backed systems (like the Tesla Powerwall or similar) can keep essential circuits running even when the grid is down, and the cost of adding a battery has dropped significantly in recent years.

Modern solar panels are warranted to produce at least 80% of their rated output after 25 years, and most continue producing power well beyond that. Some installations from the 1990s are still operating. The panels themselves rarely fail — degradation is gradual, typically 0.5% or less per year. The component most likely to need replacement is the inverter, which usually lasts 10–15 years. A quality inverter replacement typically costs $1,000–$2,500 and is worth factoring into your long-term cost calculations.

In most states, no — and this is one of the most underappreciated solar incentives. Solar does increase your home's value (studies show by about 4–7%), but over 30 states have property tax exemptions that exclude the added value of a solar installation from your assessed value. This means you get the resale premium without the higher tax bill. States with strong property tax exemptions include Arizona, California, Colorado, Florida, Massachusetts, New Jersey, New York, and Texas. Check with your local assessor to confirm what applies in your area. For more on the resale value side, see our article on how solar affects your home's resale value.

Solar panels are low-maintenance by design. In most climates, rain is enough to keep them clean. In dry or dusty areas, a periodic rinse with a garden hose helps. Inspect annually for debris, bird nests, or physical damage. Most modern inverters include monitoring apps that show real-time production data — a sudden drop in output is usually the first sign of a problem. Quality panels come with 25-year performance warranties, and a reputable installer will also carry a workmanship warranty of at least 10 years. See our guide on what to ask your installer for the right questions to cover before signing.