Retrofit Energy Capex Calculator

Retrofits cut energy cost. This calculator packages.

Building SF

LED cost/SF

Insulation cost/SF

HVAC cost/SF

Energy savings %

Current annual energy

Payback years

12.84

Total retrofit cost

$712,500

Annual savings

$55,500

How the math works

Total = SF × sum(per-SF costs). Savings = current energy × savings %. Payback = total / savings.

75,000 SF × $9.50/SF = $712k retrofit. 30% savings on $185k = $55.5k/yr. Payback 12.8 years. After rebates/credits: likely 9-11 years. Marginal. LED-only package typically wins — reduce scope for faster payback.

How to Use

Enter building SF.
Enter LED upgrade cost/SF.
Enter insulation upgrade cost/SF.
Enter HVAC upgrade cost/SF.
Enter energy savings % of current.
Enter current energy cost.
Read payback.

Frequently Asked Questions

Typical packages?

LED lighting retrofit: 30-50% lighting energy cut. Insulation improvement: 15-25% heating/cooling cut. HVAC variable speed drives: 10-20% HVAC energy cut. Combined package: 25-35% total energy reduction achievable on 1980s-90s building.

Payback?

Simple LED: 2-4 years. Insulation upgrade: 5-8 years. HVAC VFDs: 3-6 years. Full package: 4-8 years blended. Utility rebates reduce 10-25%. Tax credits (45L, 179D) add 5-15%. With rebates/incentives: 3-6 year package payback.

Maintenance?

LEDs reduce maintenance (50,000+ hour lives vs 10,000 for fluorescent). Insulation: zero ongoing cost post-install. HVAC controls: minimal added maintenance. Energy savings compound with reduced O&M — full benefit exceeds utility savings alone.