Unilever saves 246 tonnes of CO2 using LED SONs replacements at its food processing factories


Two Unilever food processing sites have allegedly netted £46,500 of savings a year in energy costs, thanks to a turn-key project to convert its external and internal SON lighting to LED.

At Unilever’s condiments processing site in Norwich and its margarine factory in Purfleet, Essex, energy waste was increasingly becoming a problem. A key culprit was identified as the outdated SON lighting. Both internally and externally, the inefficiency of the old-style lamps was not only driving up energy use and CO2 emissions, but also inflating maintenance costs, with regular lamp replacement needed.

LED technology, with its low energy consumption and long lifespans, seemed like an obvious solution to the problem for Unilever. However, complete replacement of the lighting, both outdoors and indoors, would have caused extensive disruption to production cycles. Instead, a retrofit solution was called for: LED lamp replacement in the existing SON fittings.

Unilever selected Energys Group to carry out the upgrade.

At Unilever’s Purfleet site, Energys installed 73 of the LED replacement lamps throughout the factory’s production preparation area. At the Norwich site, the original SON lamps were replaced both internally and externally, with 202 LED replacement lamps installed in the warehouse, loading bay, and around the site’s perimeter.

Supplied in a range of power outputs, the LEDs can be used to replace SONs of between 70W and 400W. In this way, Unilever was able to ensure that it received good light quality at the desired brightness throughout its sites – but at a much higher efficiency. In fact, with an efficacy of up to 140 lumens per Watt and a typical lamp lifespan of 50,000 hours (MTBF), the LED replacements have been able to deliver significant savings for Unilever.

As a result of the project, Unilever’s Norwich site has achieved £27,500 savings in annual energy bills, with a corresponding carbon reduction of 142 tonnes of CO2. The estimated payback period is just 18 months. At the Purfleet sitethe retrofit LED lighting will pay for itself in less than 9 months. Unilever Purfleet is saving £19,000 a year on energy, with CO2 savings of 104 tonnes.

Kevin Cox, managing director of Energys Group, commented: “Metal halide and sodium SON lamps, used widely in industrial contexts like the Unilever factories in Norwich and Purfleet, are falling in popularity, due to their burden on both energy consumption and maintenance needs. At the same time, LED retrofit products are coming of age."

He added: “Combined, LED replacement of its SON lamps has netted a combined saving of more than £45,000 a year on energy for Unilever, with extremely rapid payback periods achieved. This is because LED replacement can now provide good light quality, high efficiency, long lifespans – and, most importantly, a level of affordability that has previously been unseen.”