Case study · Industrial & manufacturing
Case study · Industrial & manufacturing
Executive summary
Saint-Gobain Gyproc manufactures plasterboard and gypsum products on a floor that runs on shift, where lighting is a production input rather than an amenity. Converting the manufacturing floor and storage areas to LED removed an estimated 374,748 kWh a year, a reduction of about 63%, and released an estimated 43 kVA of maximum demand. The work paid for itself in an estimated 13 months, the shortest payback in our published set. All figures on this page are estimates.
374748kWh
Energy saved per year
(estimated)
63.2%
Reduction in lighting
energy (estimated)
13mo
Payback on the
retrofit (estimated)
386tCO₂e
Carbon avoided per
year (estimated)
43.0kVA
Maximum demand
released (estimated)
Figures are estimates derived from project close-out data and standard operating assumptions. They will vary with tariff, run hours and site conditions, and are indicative of this project rather than a guarantee of results on another site.
The project
Shift manufacturing is where lighting economics are at their most brutal and their most rewarding. A floor running two or three shifts burns its lighting for two to three times the hours an office does, on fittings that were specified when the plant was built and have depreciated ever since.
High-bay lighting depreciates in a way that is easy to miss. Output falls gradually across the life of the lamp, so the floor gets darker at a rate nobody notices day to day, and the people working under it compensate rather than complain. By the time a fitting is obviously failing it has been under-performing for years.
Access is the other cost. Changing a lamp at high-bay mounting height over a live production line means equipment, a permit and usually a production stop. The maintenance line in the budget understates the true cost by a wide margin.
Scope was deliberately not the whole site. The manufacturing floor and storage areas were converted because that is where the hours are concentrated; converting the offices as well would have added cost to a project whose return comes almost entirely from the production areas.
That decision is why the payback is an estimated 13 months rather than two years. Scoping a retrofit to the long-hours areas first is the single highest-leverage decision in an industrial lighting project, and it is the one most often got wrong in the interest of tidiness.
The remaining areas were left as a defined second phase rather than as an oversight, so the site has a costed plan rather than a half-finished estate.
Why it worked
Carried forward
Resist converting the whole site at once. Scope the long-hours areas first, publish the payback they return, and let that result fund the rest. A 13-month payback on half a site is a far easier approval than a two-year payback on all of it.
Supporting references
Tell us the areas, the hours they run, the lux you need to hit and your capex envelope. We'll come back inside the week with a design, a fitting schedule and a payback model.
Related: Industrial & manufacturing LED