A popular Fortune 500 food retailer needed to reduce HVAC system energy costs and facilities maintenance. Improving energy efficiency and reducing energy costs are goals of the company’s sustainability program and directly tied to the company’s profitability. The company follows internal green building standards and practices to guide investments on energy-related solutions that maintain or enhance customers’ shopping experience.
HVAC, refrigeration, and pump systems account for 45% of a commercial building’s electric bill. The company’s Global Director of Energy Management worked with the facility manager in Cupertino, California to explore viable and proven options for making its HVAC system more efficient and reliable. The system made up a large percentage of the store’s operating cost. Maintenance costs also needed to be addressed specific to its Variable Frequency Drive (VFD) motors that failed repeatedly when bearings overheated. Lacking sub-metering and the ability to closely monitor HVAC fan motors, the solution needed to provide intelligent controls and optimal system monitoring. It also needed to be more reliable and fault tolerant.
The store’s facilities contractor, Key Mechanical, recommended using the SMC Smart Motor System to address these needs. Specifically, it replaced two, single-speed, three-year-old Baldor supply fan motors in two rooftop air handling units with SMC motors, a Smart Motor Drive, and a controller. The controller featured a wireless LAN connection to each RTU to establish a two-month energy baseline for all heating and cooling modes. Run hours for each mode was determined using data from the Building Automation System. A power meter was also installed.
The company is an American supermarket chain that specializes in selling food products without artificial preservatives, colors, flavors, sweeteners, and hydrogenated fats. It has hundreds of stores in North America and the United Kingdom. This national grocery retail is recognized as one of the industry leaders.
As a Better Buildings Challenge Partner, the company is using sub-metering and monitoring tools to measure, analyze, and publicly share the performance of newly designed and replicated energy efficiency and climate protection initiatives in new and retrofitted stores. The company is working with manufacturers, trade allies, industry peers, the Department of Energy, the Environmental Protection Agency and other organizations to further its energy efficiency goals. For example, it is also participating in the Department of Energy’s Better Building Alliance’s Advanced Rooftop Unit Challenge and hopes to help transform supermarket building energy systems nationally.
Comparing baseline data to data collected after the motors were installed and applying a weighted average for heating and cooling modes, the company realized annualized HVAC motor savings between 46-48%.
The upgraded system achieved over 80% savings during ventilation mode and over 30% savings during the heat/cool mode while maintaining comfort for employees and shoppers (chart right).
The increased efficiency supports the company’s commitment to reduce energy intensity by 20% from a 2010 baseline by 2023.
By replacing two of its RTU fan motors, the company achieved total annualized fan energy savings between 46-48% percent. Savings were so significant that it committed to upgrading additional stores with the SMC Smart Motor System.
According to a paper put out by the Retail Industry Leaders Association, Energy Saving Opportunities and Tactics for Retail, by installing high-efficiency units, supermarkets can save up to $52,000 per year–or up to $8,700 per RTU–in energy costs. Retrocommissioning an existing HVAC unit can save up to 20 percent of HVAC energy costs and replacement with high-efficiency units can yield site energy savings between 2.1% – 5.8%.
TOTAL ANNUALIZED FAN ENERGY SAVINGS