Refrigeration

Q: Guests in my inn often ask if I have a vending machine for beverages on the premises, so I'm considering getting one and I'm doing some research. I've been hearing about a gadget that lowers the amount of energy a vending machine uses. What can you tell me about that? - MN, Newport, VT

Dan:

The device you've heard about is a simple, plug-in controller that completely powers down a vending machine when the area around it has been vacant for 15 minutes. It does this by using a passive, infrared sensor, which then turns the vending machine's power on when it detects movement nearby. It also periodically turns on, to keep products cold. I highly recommend it.

Paul:

I agree. On average, a cold-beverage machine costs about $350 per year to operate in Vermont. With a vending controller, you can reduce that cost by about $133 per year in high-traffic areas and by about $200 annually in low-traffic locations. Vending machine controllers also reduce maintenance costs and extend the life of the vending machine by significantly reducing the number of times the compressor cycles on and off, to keep the unit cold.

Dan:

To ensure that products stay cold, the controller automatically re-powers the machine at one- to three-hour intervals, depending on the room's temperature. Independent testing by both the Coca-Cola^® and the Pepsi-Cola^® companies determined that one such control - the VendingMi$er - does not adversely affect product quality or the vending machine itself.

Paul:

The VendingMi$er retails for $179. Efficiency Vermont offers an incentive of $45toward the cost of each unit purchased and installed, bringing the net cost to $134. This makes it possible to recoup the purchase price through energy savings in about a year. You can download an incentive form from the Business Rebate Center at www.efficiencyvermont.com. You may also be able to get incentives for similar products.

Dan:

Another way to reduce vending energy use is with ENERGY STAR^® qualified beverage vending machines, which are 50% more energy-efficient than standard models. These units incorporate more efficient compressors, fan motors, and lighting systems and come with an option that operates the machine in low-energy lighting and/or low-energy refrigeration states during times of inactivity. An advantage of these machines over vending controllers is that they come in both indoor and outdoor models, while controllers are designed only for indoor use. Note: If you have refrigerating vending machines (whether ENERGY STAR or not) outdoors, place them on the north or east side of a building, to avoid direct summer sun. That sunlight makes it hard for the condenser to release heat from the unit. This problem also can occur in unconditioned foyers and indoor pool areas.

Paul:

An ENERGY STAR qualified vending machine can reduce yearly electricity costs by about $150, compared to a non-ENERGY STAR model. If you establish a contract with a vendor operator, ask about getting a new or rebuilt ENERGY STAR unit. Efficiency Vermont may be able to work with your vendor to help offset the additional cost of these machines.

Dan:

Whether you go with a vending controller or an ENERGY STAR machine, you?ll be doing your bottom line a favor while you provide your guests with the vending convenience they want.

Q: The cooler in my convenience store seems to run all the time. What's more cost-effective-repairing it or replacing it? And can you tell me about any new energy-saving technology for freezers and coolers?

- AR, South Hero

Paul:

Big question, especially since every case is different. Basically, a cooler has two parts: the insulated container that holds everything and the refrigeration system that keeps it all cool.

Dan:

Let's start with the container. The most important part of the container is the insulation. A container with fiberglass insulation, or with little or poorly installed insulation of any kind, might be a good candidate for replacement with a factory made foam insulated container. Air leaks cause your refrigeration system to run more often, so make sure the container is as air tight as possible. If it's homemade, try sealing it with spray foam or caulk. But if mold problems or sweat condensation are present, it?s time to look into a replacement.

Paul:

When it comes to your refrigeration system, there are many low-cost ways to improve performance. For example, cleaning the evaporator and condenser coils on a regular basis improves air flow. You could also move the compressor outside. You'll lose some "free" heat in the winter, but it will improve performance and reduce the need for air conditioning in the summer.

Remember to turn off door heaters when humidity is low. Better yet, install a humidistat to control door heaters automatically. Another step you could take is to invest in the new Lexan film that, when applied to the glass door, prevents condensation and eliminates the need for a door heater altogether.

Dan:

The benefit of a climate like ours is that you can use an economizer to bring outside air in during winter months, forgoing the refrigeration system. You can also install a Smart Defrost Controller kit that actually "learns" over time how many defrosts your system really needs, so you save energy in the long run.

If you have a hermetic compressor near the end of its life, look into replacing it with a more efficient scroll or Discus unit. You should also replace evaporator fan motors that run 24 hours a day with more efficient brushless DC motors (sometimes referred to as ECM motors).

Paul:

Efficiency Vermont offers a number of rebates as incentives for installing new energy-efficient refrigeration equipment-from tens to hundreds of dollars. To view a complete list of financial incentives available for your business, visit our Online Rebate Center.

RH Travers Company and National Resource Manager (NRM) are two sources for the economizers noted above, as well as other refrigeration equipment and controls. To locate a retailer or contractor near you, click on the Marketplace tab at www.efficiencyvermont.com.