Solar Panel Payback Calculator

Residential solar paybacks 6–14 years depending on system size, electric rate, and incentives.

$/W installed

System size (kW)

Annual production (kWh)

Electric rate $/kWh

Federal ITC %

State + utility incentives

Payback (years)

9.1

Annual savings

$1,980

Net system cost

$18,100

How the math works

Gross = $/W × kW × 1000. Net = gross − ITC − state. Savings = production × rate.

$3.50 × 8 × 1000 = $28,000 − $8,400 ITC − $1,500 = $18,100 net. 11,000 × $0.18 = $1,980/yr. 9.1 yr.

How to Use

Enter $/w installed.
Enter system size (kw).
Enter annual production (kwh).
Enter electric rate $/kwh.
Enter federal itc %.
Enter state + utility incentives.
Read payback (years).

Frequently Asked Questions

Solar panel economics?

Cost: $3.00–4.50/watt installed (8 kW system $24k–36k). Federal ITC: 30% (extended to 2032). State + utility incentives: $0–2/W in solar-friendly states (CA, NY, MA, NJ). Net metering: full retail credit common, declining (NEM 3.0 in CA reduces). Annual savings: $800–4,000 depending on usage + rate. Battery storage add-on: $10k–20k for 10–13 kWh. Lifespan: 25–30 years on panels, inverter replacement at year 12–15 ($2–4k). Best ROI: high electric rates (CA, MA, NY, HI), south-facing roof, low shade.

How accurate is this estimate?

Material and labor estimates are accurate to ±15% with reasonable inputs but local market conditions vary. Major markets cost 30–60% more than rural. Labor rates regional (union vs non-union, prevailing wage). Material prices fluctuate with commodity cycles. Get 3 contractor bids for any work over $5k. This calculator is a sanity check, not a substitute for actual quotes.

DIY vs contractor?

DIY savings: 40–70% of contractor cost on labor. Realistic skill threshold: painting, basic plumbing, simple electrical, drywall, flooring. Pro required: structural, gas, complex electrical, HVAC, roofing (warranty + insurance), permits. Permitted work without license risks insurance and resale. Time: hobby DIYers 3–5x slower than pro. Tools and learning curve real.

Permit and code compliance?

Permits required for: structural changes, additions, electrical service changes, plumbing rough-in, HVAC replacement, roof replacement (varies), fence (varies). Cost: $50–2,000+ depending on scope. Skipping permit risks: stop work order, fines, forced removal, insurance denial, resale title issues. Always pull permit; cost is small relative to compliance friction.