UV Curing calculator

UV LED Payback Calculator

UV LED retrofits look great on paper but capital review wants a payback number that holds up to scrutiny. This calculator combines the all-in retrofit installed cost (LED head, driver, controller, install labor, validation), the annual savings from mercury (energy + lamp purchases + scrap from intensity decay), and the ongoing LED maintenance cost into a clean years-to-payback and a five-year net — exactly the format most CFOs accept on a UV cure line.

What this calculator does

  • Compare a UV LED retrofit's installed cost against the annual mercury energy + lamp + scrap savings to see years to payback.
  • Use it to build a capital-request payback case for a mercury-to-LED retrofit, or to test whether vendor-quoted savings hold up against your real lamp and energy numbers.
  • Returns years to payback and a five-year net for a UV LED retrofit replacing a mercury arc UV cure system.

Formula used

  • Net annual savings = annual mercury savings − annual LED maintenance
  • Payback (yr) = retrofit installed cost ÷ net annual savings
  • Five-year net = net annual savings × 5 − retrofit installed cost

Inputs explained

  • Retrofit installed cost: LED head + driver + controls + install labor + qualification — not just the LED hardware quote.
  • Annual mercury savings: Sum of energy savings, lamp purchase savings, and scrap savings vs the current mercury baseline.
  • Annual LED maintenance: Driver replacement reserve, optical cleaning, periodic radiometer / re-validation cost.

How to use the result

  • Use it during capex sizing, vendor evaluation, and any time a retrofit case needs to clear a corporate hurdle rate.
  • Treats annual savings as flat — real LED systems give the biggest savings in years 1–3, then taper as LEDs age. Doesn't capture quality wins (better dose stability, no warm-up, dim-on-demand), throughput wins (faster line speed where dose was the bottleneck), or non-economic factors like mercury elimination compliance.

Common questions

  • What is a healthy payback for a UV LED retrofit? 1–3 years on multi-shift production lines is the typical sweet spot — energy and lamp savings dominate. 3–5 years is normal on single-shift or low-utilization lines. Past 5 years it's usually a quality or compliance case (mercury elimination), not an energy case.
  • What should annual mercury savings include? Three pieces: (1) energy delta from Mercury UV Lamp Energy Cost minus UV LED Energy Cost, (2) eliminated mercury lamp purchases per year, (3) scrap/rework reduction from steadier dose. Vendors often only show #1 — push for #2 and #3 to make the case real.
  • How do I cost annual LED maintenance? Drivers and controllers are the wear items, not the LEDs themselves. Budget ~5–10% of LED hardware cost per year as a maintenance reserve, plus the cost of a yearly radiometer pass and the occasional optical window cleaning. Keep it conservative — you'd rather show payback hit early.
  • Should I include throughput gains? Only if you're confident the line speed was actually dose-limited and you can run faster after the retrofit. Throughput gains usually exceed energy savings on bottleneck lines, but they belong in a separate gain-share line so the payback math stays defensible.

Last reviewed 2026-05-12.