Commercial
Commercial LED retrofit: how to model the payback honestly
10 June 2026 · 5 min read
A straightforward method for calculating lighting energy savings, maintenance savings and realistic payback on a warehouse or office retrofit.
Lighting is often the largest single controllable electrical load in a warehouse or older office. Replacing fluorescent or metal halide fittings with modern LED typically cuts lighting consumption by 50 to 70%, but the savings quoted in sales literature rarely reflect how a building is actually occupied.
Model it in three parts. First, measured load: fitting count multiplied by circuit watts, multiplied by real annual running hours, not nominal opening hours. Second, maintenance: lamp and ballast replacements avoided, plus access equipment for high bay areas. Third, controls: presence detection and daylight dimming often deliver as much saving again in circulation and perimeter zones.
Where the number lands matters less than whether it survives scrutiny. A retrofit that pays back in three years with conservative assumptions is a better business case than one that pays back in eighteen months on optimistic ones.
We survey, model and install, and we will tell you when a retrofit does not stack up yet.
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