Lighting, LEDs & Electrical Fixtures worked example

LED Retrofit Payback with total retrofit investment of 9,000 $: a worked example

Suppose total retrofit investment falls to 9,000 $. This page works the full calculation at that level so you can see exactly which result moves and by how much. Calculate the simple payback period for an LED retrofit project by comparing total upfront investment against net annual savings from energy reduction and maintenance cost avoidance. Also shows 5-year net value.

The inputs for this scenario

  • Total retrofit investment: 9,000 $ (the input this scenario stresses; the baseline uses 18,000)
  • Annual energy savings: 4,200 $ / yr (held at the documented default)
  • Annual maintenance cost savings: 1,100 $ / yr (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Net annual savings = annual energy savings + annual maintenance savings.
  • Payback period works out to 2.9 yr at these inputs, and this is the headline figure for the scenario.
  • Net annual savings (energy + maintenance) works out to 3,100 $ / yr at these inputs.
  • Total retrofit investment works out to 9,000 $ at these inputs.
  • Five year net works out to 6,500 $ at these inputs.

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 50% below the baseline at 2.9 yr.
  • It computes the simple payback period and five-year net value of a lighting retrofit from its cost and combined annual savings. When the numbers land here, the stressed input is the lever to work; the walkthrough above shows exactly how much each output recovers as it climbs back toward the baseline.

Results at a glance

  • Payback period: 2.9 yr (headline result)
  • Net annual savings (energy + maintenance): 3,100 $ / yr
  • Total retrofit investment: 9,000 $
  • Five year net: 6,500 $

Run it with your numbers

  • To rerun this with your own numbers, open the live LED Retrofit Payback calculator, set total retrofit investment to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.