Energy-Saving Tips for Grocery & Convenience Stores
Low-Cost Refrigeration
Harnessing Outdoor Air for Energy Savings
As Vermont businesses brace for higher energy bills each winter, many grocers are welcome the cold weather. That's because of an electricity-saving technology that uses cold, outdoor air to reduce refrigeration system run times in walk-in coolers.
"It's called an outside-air or refrigeration economizer," explains Susan Thompson of Efficiency Vermont. "The energy savings can be significant, and not just in the winter. Up here in the north, we can take advantage of this technology during much of the fall, winter, and spring. This can result in a positive return on investment in less than two years."
An economizer reduces energy use by automatically introducing outside air into a walk-in cooler when outside temperatures fall below the refrigerated-box temperature. A fan-and-damper system, which brings in the cold outside air, uses less energy than the cooler's compressor and condenser fans would use to achieve the same results. A filter prevents dirt and pests from entering, and the dampers close automatically in warm weather.
"With an economizer, compressors need to run far less often, and condensing units operate up to 20% less," says Thompson. "This technology is a suitable match for Vermont's cold winters. It harkens back to basic, frugal Yankee common sense, like cooling butter in a springhouse over a stream."