This case study sheds light on how Danfoss enabled a leading French retailer to achieve significant savings on its energy bill by implementing integrated control of refrigeration, HVAC, and lighting systems. The integrated control system, now implemented in more than 700 stores across France, has affected a 46% savings during nighttime and weekends, and 20% savings during the daytime.
Introduction
It is a widely known fact that commercial buildings contribute to a sizeable percentage of energy consumption and emissions, and a building’s cooling requirements contribute to nearly 50% of its energy consumption. In this regard, commercial buildings need to maintain a precise balance between dynamic growth and sustainable management. Whether it’s hotels, offices, supermarkets or other public spaces, building technology must adapt to market needs and the regulatory requirements.
HVAC-R solutions from Danfoss are stated to be tailored to affect energy and cost savings for the building, without compromising on the functional and comfort requirement of the building.
Substantial Energy Savings with Integrated Store Control
In close cooperation with Danfoss, the retailer installed frequency converters on the pack and introduced integrated electronic control of evaporators, cold rooms, air conditioning, heating, and lighting inside the supermarket and outside in the parking lot.
Implementing the Smart Store installation, at a demo store in France – was the first and a major step towards proving that – by adding a simple technology, and significant energy savings can be achieved. Since then, the interest in the smart solution has been wide and now the retailer has fitted over 700 stores with similar solutions.
Simple Solution with a Pay-back Time of Less than One Year
Before Smart Store Installation: the following were the working conditions of the stores with respect to lighting and cooling:
-Store lighting was manual, to be operated by switch
-All lighting was turned on from the time of the staff’s arrival throughout the day, even during the midday close
-Light Zoning amenities were not prevalent
-The parking lot would remain lit through the night
-Cooling not optimized: despite the presence of curtains on the cabinets, the set points were not lowered at night
-The floating HP was not activated, and the pack was oversized in winter and mid-season.
After Smart Store Installation: the following changes were implemented:
-Variable speed installed on existing compressor and condenser, enabling floating HP setting and night set-point modification
-The existing controller was replaced by SC 255 for integrated control of refrigeration, light and HVAC
-Light zoning was introduced inside store and in the parking lot to ensure optimised power usage
-A reversible heat pump was installed, which runs based on a pre-fixed scheduled and temperature thresholds (high in winter and low in summer) basis the outdoor temperature.
The Savings
The test installation in France is testament to the fact that the new pack control and variable speed on compressors and condensers, combined with integrated control of all electrical installations in the supermarket, return substantial energy savings while keeping in mind food safety and the convenience of shoppers. The solution has been replicated in several stores today, enabling them to save energy and tackle global climate challenges resultant of excessive energy consumption. The tests returned the store’s average energy savings up to 46% during nighttime and weekends, and up to 20% during daytime.
Conclusion
Danfoss’ solutions catering to commercial buildings have proven to affect significant savings on cost and energy and are applicable in various markets. Whether it is for supermarkets, or hotels, or hospitals, Danfoss’ range of offerings such as air handling units, chillers, building monitoring systems have gone a long way in not only enhancing comfort, but also ensuring that these buildings run efficiently and reducing their overall carbon emissions.
