Deliver greater energy savings to an efficient LED lighting system already installed throughout a building? This was the challenge set out by TESCO to help them optimise power consumption within their flagship Cheshunt store. The solution involved Llumarlite developing a project specific lighting control system that integrated with the incumbent Trend system allowing us to optimise power consumption in the store throughout the week to delivering a saving of 36%.
Over the past few years Tesco have been installing energy efficient LED’s across their stores, helping to reduce power consumption and CO2, but they wanted to achieve more. Llumarlite and Tesco have a longstanding partnership, successfully working together across multiple stores within their estate and we were excited to find a way of delivering greater energy savings from the efficient LED’s currently installed within their flagship Cheshunt store at Brookfield farm.
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End of aisle
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Self-service area near the front of the store entrance
With the challenge laid down Llumarlite undertook an in-depth analysis of the Cheshunt store’s energy performance and existing equipment. Through on and off-site research, a comprehensive picture of how this busy store, open 24 hours for 6 days with reduced Sunday trading hours, operated and performed throughout the week. Further development undertaken involved bench testing sample luminaires to check the compatibility and response of the existing Dali Dimmable LED Drivers within the luminaires. A fully loaded mock-up assembled off-site was used to prove the proposed Dali control system solution would operate the existing circuits which challenged the maximum number of Dali sub-address nodes. This was also used to prove our methods of control, handshake and feedback would be possible using the incumbent Trend IQ system already in place.
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Daylight photocell commissioning
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Controls testing of the dimming
A presentation of the potential energy savings and a practical demonstration of the technical aspects to the project was undertaken with the key stakeholders. TESCO, happy with the results, commissioned Llumarlite to begin implementing the proposed changes. Working closely with the Cheshunt Store’s management team, the new system was installed and commissioned through a phased work plan. This avoided any disruption to the daily trading of the store. The first phase saw the implementation of our initial research, including repair of existing equipment and careful application of the correct control philosophy to optimise the store’s timings and light levels to operational hours. The second phase introduced dimming controls to the main store lighting. These were commissioned to maximise available savings based on site surveyed lighting levels and aesthetic feedback in collaboration with TESCO staff.
Power consumption data was continually monitored before and after each energy saving phase. Data gathered during each phase gave clear indications of the benefits during installation. Phase 1, using the latest control philosophy, optimising the store’s timings and light levels produced a measured saving of 20%. Phase 2, introduced dimming controls to the main store lighting produced a measured saving of 16%. Overall, phase 1 & 2 combined saved a total of 36%, furthermore, savings between the previous maximum load to the optimised minimum demonstrated savings potential of up to 48%. The project proved that huge savings and improvements can be achieved to even the latest generations of efficient LED luminaires when the right controls are selected. In addition to optimising light levels throughout the day for customers and staff, the project also reduced the stores CO₂ emissions and provided savings to operational costs through reduced maintenance and longer product lifecycle.
