This blog summarizes an article from ACHR NEWS, entitled “Refrigeration Retrofits Offer ‘Cool’ Savings for Supermarkets.” Click here to read the article in its entirety.
The commercial refrigeration system is the biggest energy user in supermarkets, accounting for about 40 to 60 percent of electricity consumption, according to the Environmental Protection Agency (EPA). For food retailers, getting energy consumption under control is a top priority, and the refrigeration industry has stepped in with new, higher-efficiency equipment and technologies, such as advanced monitoring and control via the internet of things (IoT). However, for many retailers, virtually all their equipment is aging, and buying new equipment and systems across the board would be prohibitively expensive. But there is another path to saving a considerable amount of energy: targeted retrofits or upgrades to their existing systems.
Some energy-saving modifications can be simple and obvious, such as adding doors to cases. But at a recent Emerson E360 Forum, I explained how a systematic approach to retrofits and upgrades can identify savings throughout a store’s entire refrigeration infrastructure, particularly older, energy-demanding direct expansion (DX) centralized systems. It is a six-step process that reveals the primary causes of energy loss and, step by step, proposes energy-saving retrofits and upgrades to your system that can systematically reduce energy costs without breaking the bank.
- Conduct a baseline energy audit. Throughout the store by installing energy-monitoring equipment. These sensors help you analyze the existing energy signature of the entire store before you make any adjustments or retrofits, and will also be invaluable for future temperature monitoring and control to ensure food safety and quality.
- Recommission your existing equipment to factory specifications. This may include adjusting setpoints, superheat, suction pressure and other settings. In the process, any broken components can be repaired. This one step alone can result in energy savings of 18 percent or more.
- Upgrade your refrigeration technologies. One effective upgrade is changing discus compressors to digital compressors. This single retrofit can reduce compressor cycling, increase system reliability, and improve energy efficiency by 16 percent or more. Installing variable-frequency drives on condenser fan motors can save even more.
- Upgrade your HVAC system. Ambient store temperatures are major stressors on refrigeration systems. Consider upgrading rooftop units and adding demand-controlled ventilation and humidity controls. Integrating the rooftop units with the refrigeration system in the store is another option, creating a self-contained ecosystem that balances ambient and refrigeration temperatures for significant energy savings.
- Upgrade lighting and other renewables. Adding modern lighting technology lowers temperatures. Installing doors onto units lowers energy losses. Electronic case controls and expansion valves (EEVs) fine-tune equipment temperatures, while upgrading to electronically commutated (EC) motors lowers electricity consumption while improving equipment efficiency.
- Perform condition-based maintenance. Once you’ve migrated to these capital upgrades, it’s important to step up your regular maintenance intervals to continue your gains in efficiency and cost savings.
With these targeted retrofits and upgrades, you can systematically make your centralized DX system more effective in maintaining food quality and safety while simultaneously uncovering efficiencies that can result in significant savings.