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Energy Retrofit Payback Calculator
Energy retrofits — LED, HVAC controls, insulation, window upgrades, deep building retrofits — pay back over 1-25 years depending on scope. Net cost after IRA tax credits, utility rebates, and C-PACE financing can cut headline cost by 30-50%, dramatically improving payback. This calculator computes simple payback, total horizon savings (with energy inflation), and ROI.
Simple payback (yrs)
6.3
Net retrofit cost (after incentives)
$72,500
Total horizon savings
$213,888
Total ROI %
295.02%
How the math works
Energy retrofit payback = net cost ÷ annual savings. Common retrofits and typical paybacks: LED lighting 1-3 yrs; HVAC controls 2-5 yrs; insulation 5-10 yrs; window replacement 10-25 yrs; deep retrofit 8-15 yrs.
IRA tax credits (179D, 25C, 25D) plus utility rebates can cut net cost by 30-50%, dramatically improving payback. C-PACE financing lets owners spread cost over 20+ years.
How to Use
- Enter retrofit cost and projected annual energy savings.
- Enter rebates and tax credits available.
- Enter energy inflation % and analysis horizon.
- Read simple payback, net cost, total savings, and ROI.
Frequently Asked Questions
Typical payback ranges?
LED lighting 1-3 yrs; smart HVAC controls 2-5 yrs; envelope insulation 5-10 yrs; window replacement 10-25 yrs; deep retrofit 8-15 yrs.
What incentives are available?
179D commercial buildings deduction up to $5/SF; 25C residential energy credit up to $1,200/yr; utility prescriptive rebates $50-500/measure; C-PACE financing 20-30 year terms tied to property tax bill.
Should I include energy inflation?
Yes — 3-5% annual is reasonable. Without inflation, paybacks look longer. With realistic inflation, deep retrofits become attractive.
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