Lighting, LEDs & Electrical Fixtures worked example

LED Retrofit Payback with total retrofit investment of 45,000 $: a worked example

This scenario runs the led retrofit payback calculation on the strong side: total retrofit investment of 45,000 $, with every other input held at its documented default. Use this when preparing a lighting retrofit proposal, justifying the capital cost of an LED upgrade to facility management or finance, comparing different LED product options by payback, or responding to a customer asking how long before the investment pays for itself.

The inputs for this scenario

  • Total retrofit investment: 45,000 $ (raised for this scenario; the documented default is 18,000)
  • Annual energy savings: 4,200 $ / yr (unchanged)
  • Annual maintenance cost savings: 1,100 $ / yr (unchanged)

Working through the calculation

  • Applying the documented formula (Net annual savings = annual energy savings + annual maintenance savings) to the inputs above produces each figure below.
  • At this operating point the engine returns 14.52 yr for payback period, the number this scenario is built around.
  • At this operating point the engine returns 3,100 $ / yr for net annual savings (energy + maintenance).
  • At this operating point the engine returns 45,000 $ for total retrofit investment.
  • At this operating point the engine returns -29,500 $ for five year net.

How this compares with the baseline

  • Against the tool's baseline example, where total retrofit investment sits at 18,000 $ and the headline result is 5.81 yr, this scenario comes in 150% above the baseline at 14.52 yr.
  • Use it to screen a retrofit proposal, compare projects competing for capital, or build the savings case for a rebate application. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Payback period: 14.52 yr (headline result)
  • Net annual savings (energy + maintenance): 3,100 $ / yr
  • Total retrofit investment: 45,000 $
  • Five year net: -29,500 $

Run it with your numbers

  • Every input above is editable in the live LED Retrofit Payback calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.