One of the key ways for Sainsbury’s to achieve this was to use lighting in stores more ef ciently. Research showed that a digital lighting control system can provide an energy saving of approximately 30 per cent if it is implemented correctly. However, it was important that in addition to being cost ef cient, any changes to the lighting system should not impinge on customers’ in-store experience.
Prior to the installation, lighting used approximately 20 per cent of a new store’s energy usage. The only way of controlling light was manually through relay panels which tended to be bespoke depending on the size of the stores and who was the installing contractor. Sainsbury’s was looking for a standardised solution to minimise consumption by utilising daylight as much as possible and also cut the energy by effectively managing less frequently used areas during operational hours. One other key requirement was to ensure that during non- trading hours, lux levels be set to a minimum level to allow for maximum energy ef ciency while still allowing staff enough light to restock the shelves.
Sainsbury’s, in conjunction with Schneider Electric and Symphony Automation, an expert C-Bus system integrator, developed a design that could be used in all supermarkets regardless of layout. Special consideration was given to utilising natural sunlight through the use of daylight harvesting technology in order to become less reliant on arti cial lighting.
Sainsbury’s tested a number of different systems before choosing to install Schneider Electric’s Clipsal C-Bus system in 400 of its stores across the UK. Schneider Electric was chosen due to both cost effectiveness and reliability of the system.