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brian austin
brian austin

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Solar Panel ROI in 2026: The Math That Makes It a No-Brainer (or Not)

#beginners #finance #webdev #green

Everyone says solar "pays for itself." But when? And for who? Let's do the actual math instead of trusting a salesperson's spreadsheet.

The Core Variables

  1. Your monthly electric bill — This determines your system size
  2. Sun hours per day — Varies by location (Phoenix: 6.5, Seattle: 3.5, Chicago: 4.5)
  3. System cost per kW — Average $2,800/kW installed in 2026
  4. Federal tax credit — 30% through 2032 (Inflation Reduction Act)
  5. Your actual offset — Solar typically covers 80-90% of usage, not 100%

The Quick Formula 

System size (kW) = (monthly bill / $0.12 per kWh) / (sun hours × 30 days)
System cost = size × $2,800
Net cost = system cost × 0.70  (after 30% federal credit)
Annual savings = monthly bill × 12 × 0.85  (85% offset)
Payback = net cost / annual savings
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Real Examples

$150/month bill in Central Illinois (5 sun hours):

  • System: 8.3 kW → $23,333 → $16,333 after credit
  • Saves: $1,530/year
  • Payback: 10.7 years
  • 25-year savings: $21,917

$250/month bill in Phoenix (6.5 sun hours):

  • System: 10.7 kW → $29,915 → $20,940 after credit
  • Saves: $2,550/year
  • Payback: 8.2 years
  • 25-year savings: $42,810

$100/month bill in Seattle (3.5 sun hours):

  • System: 7.9 kW → $22,222 → $15,556 after credit
  • Saves: $1,020/year
  • Payback: 15.3 years
  • 25-year savings: $9,944

When It Doesn't Make Sense

  • If your bill is under $80/month, the payback period exceeds 15 years
  • If you're moving within 7 years, you probably won't recoup the cost
  • If your roof needs replacement soon, do that first
  • If you're in a very low-sun area, the math gets brutal

When It Absolutely Makes Sense

  • Bill over $150/month in a sunny state = almost always wins
  • Planning to stay 10+ years = clear winner
  • Electric rates rising 3-5% annually = payback accelerates over time

I built a free calculator at simplylouie.com/solar-calculator that runs these numbers instantly. No signup, no email gate, no solar company lead gen.

Free tools at SimplyLouie — built to be useful, not to sell you anything.

SimplyLouie is a $2/month AI assistant powered by Claude. 50% of every subscription goes to animal rescue.

Try it free: simplylouie.com | Free Tools | Free VIN Decoder | Telegram: @LouieLifeBot

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