Q. A couple years ago, we had good results upgrading to energy-efficient lights at our family’s restaurant. We lowered our electric costs and we actually like the lighting better. Now we’re ready to look into another energy-saver project that will lower the electric bill some more. What would you say is the best next step? If it helps: Our biggest piece of equipment is our walk-in cooler. - PN, Orange County
Paul:
You’re wise to be making efficient upgrades; energy demands in food service facilities are roughly 2.5 times more per square foot than in most commercial buildings. Your best next step depends on a number of factors, including your budget and the age of your equipment. Generally, the top opportunities for energy savings in food-service operations are lighting, refrigeration, food preparation equipment, and ventilation.
Dan:
It’s great that you addressed your lighting first. I suggest turning to refrigeration next. Let’s start with the simplest actions and then move to energy-saving investments. For example, keep the cooler well stocked. This will help the cooler stay cold longer, reducing the amount of time the refrigeration system is active. You also can reduce system run times if you keep evaporator and condenser coils clean, to improve air flow.
Paul:
It’s essential to consider the air-tightness of your refrigeration equipment. If a unit has gaps or cracks where warm air can enter and cool air can escape, the cooling system will have to work harder to keep up. A refrigeration contractor can check your cooler's door seals for air tightness. Also, set refrigerator temperatures no lower than required by health code.
Dan:
A great energy saver for a walk-in cooler is an outdoor-air economizer. This equipment reduces energy use by automatically bringing outside air into the cooler when outdoor temperatures fall below the refrigerated-box temperature. With an economizer, compressors and condensing units run up to 20% less. If you install an evaporator fan motor control with the economizer, you can save even more in some walk-ins because it will shut down some of the evaporator fans when the compressor isn’t running. Note: I don’t recommend an economizer if you keep unpackaged items in your cooler, as they can become dry.
Paul:
To reduce operating costs for evaporator fans (the fans visible inside your cooler or freezer), replace standard, shaded-pole fan motors with brushless DC evaporator fan motors (also known as ECM). These motors can save between $100 and $130 per fan per year in a walk-in cooler. Overall savings are greatest when combining walk-in coolers' efficient motors with evaporator fan motor controls, which Dan mentioned above.
Dan:
These motors, controls, and compressors are also important to look for when buying new coolers. Efficiency Vermont can work with you and your contractor to investigate the most cost-effective approaches for your particular business and budget. If you have questions, call 888-921-5990, toll-free.
Paul:
Efficiency Vermont provides rebates for the purchase of efficient equipment for refrigeration, lighting, ventilation, heating, cooling, and other recommended efficiency investments. Go to the Ways to Save & Rebates section of our website to download easy-to-use mail-in rebate forms. Best of luck in your efforts to cut energy costs at your family’s restaurant.