BEST PRACTICES

This section of the EVC lists some best management practices that you can employ (with regard to appliances) in the cafeterias on your campus in order to reduce energy consumption.

Energy-efficient refrigerators differ from less efficient models in the following ways: more efficient compressors, improved insulation, better door seals, improved condensers and evaporators, and more precise temperature controls and defrost mechanisms.

1. Energy-saving tips:
• Clean refrigerator condensers every three months.
• Don't keep your refrigerator and freezer too cold. Recommended temperatures are 37°F and 40°F for the fresh food compartments of the refrigerator and 5°F for the freezer section. If you have a separate freezer for long-term storage, it should be kept at 0°F.
• Regularly defrost manual-defrost refrigerators and freezers; frost buildup increases the amount of energy needed to keep the motor running. Don't allow frost to build up more than seven millimeters (one-quarter of an inch).
• Make sure refrigerator doors' seals are airtight. Test them by closing the door over a piece of paper or a dollar bill so it is half in and half out of the refrigerator. If you can pull the paper or bill out easily, the latch may need adjustment or the seal may need replacing.
• Cover liquids and wrap foods stored in the refrigerator. Uncovered foods release moisture and make the compressor work harder.
• Move refrigerators out from the wall and vacuum their condenser coils once a year (unless you have a no-clean condenser model). Refrigerators run for shorter periods with clean coils.
• Don't force your refrigerator to work harder than necessary by locating it near a heat source, such as a radiator, heating vent, kitchen range or dishwasher.
• Don't suffocate refrigerators by enclosing them tightly against the wall. Since most refrigerators reject heat from the bottom and/or back, they need adequate clearance to allow sufficient airflow. Two general rules-of-thumb are to double the space recommended by manufacturers for refrigerator installation, and to allow 2 inches of airflow around the refrigerator. Allow at least one inch of space on each side of a freezer to allow good air circulation.
• If the refrigerator has an "energy-saver" switch, adjust it to the setting that provides maximum energy savings without causing condensation on the outside of the unit.
• Thaw frozen food inside the refrigerator because it will help cool the interior and eliminate the use of energy for thawing in an oven or microwave.
• Let food cool before putting it in the refrigerator so it won't have to work so hard to keep the food cool.
• Organize the contents in the refrigerator to ensure good air circulation around the items.
• Keep freezers full; full freezers perform better than nearly empty ones.
2. Purchasing tips:
• An ENERGY STAR® refrigerator uses at least 20% less energy than a similar-sized refrigerator that just meets the minimum federal standards. ENERGY STAR® refrigerators also save, on average, $14 per year and $168 over the course of its useful life.
• Look for a refrigerator with automatic moisture control. Models with this feature prevent moisture accumulation on the cabinet exterior without the addition of a heater. This is the same thing as an "anti-sweat" heater. Refrigerator models with an "anti-sweat" heater will consume 5% to 10% more energy than models without this feature.
• Consider upgrading refrigerators; older models use chlorofluorocarbons (CFCs) as a refrigerant, and newer models use halogenated CFCs (HCFCs), which are more environmentally benign.
• When selecting a new refrigerator, choose a manual defrost model because it uses half of the energy that automatic defrost models do (just remember to defrost it periodically).
• Ask the following questions:
• Are rebates available from local utilities or government agencies for the purchase of the specific model?
• What is the energy rating? (Check the EnergyGuide label.)
• What do I need to know about the refrigerator in order to use it most effectively? (Example: How many inches should be allowed around the refrigerator for airflow?)
3. Innovative technologies:
• Evaporator fan controllers for medium-temperature walk-in refrigerators
• Applications: low- and medium-temperature walk-in refrigeration and freezer systems like those used in restaurants, cafeterias, mess halls, correctional facilities, grocery stores, bars and other custom industrial applications.
• Capabilities: reduce evaporator and compressor energy consumption and lengthens component life; and can be retrofitted into existing refrigeration systems or incorporated into the design of new equipment.
• Adsorption refrigerators that use low-temperature waste heat
• Capabilities: reduce peak demands for electricity; eliminate the use of ozone-depleting CFC refrigerants and improve electricity load factors.

1. Energy-saving tips:
• Clean ovens while they are still warm (after removing food).
• Cook as many things at once as possible.
• Use microwaves when possible, because they use less electricity than conventional electric cooking methods (microwaves cook faster and at a lower wattage).
• Preheat ovens only when necessary, and keep the preheating time to a minimum. Unless you are baking breads or pastries, you may not need to preheat the oven at all.
• Food cooks more quickly and efficiently in ovens when air can circulate freely. Don't lay foils on racks. If possible, stagger pans on upper and lower racks to improve airflow.
• Use glass or ceramic pans in ovens. You can turn down the temperature by about 25°F and cook foods just as quickly.
• Check to be sure the oven door gasket is tight. Adjust or replace gaskets as required.
• Keep range-top burners and reflectors clean; they will reflect the heat better and save energy.
• Match the size of the pan to the heating element; more heat will get to the pan and less will be lost to the surrounding air (a 6-inch pan on a 8-inch burner will waste over 40% of the energy).
• On electric stove-tops, use only flat-bottomed pans that make full contact with the element (a warped or rounded pan will waste most of the heat).
• Whenever possible, use a pressure cooker. By cooking food at a higher temperature and pressure, cooking time is reduced dramatically and energy use is cut by 50-75%.
2. If you are purchasing new products for or upgrading your cafeteria, here are some purchasing tips:
• Try to buy self-cleaning ovens because they use less energy for actual cooking because of higher insulation levels.
• Gas ovens use much less energy compared to their electric counterparts because the fuel is used directly for cooking. A gas appliance also costs less than half as much money to operate as an electric one does, provided it is equipped with electric ignition instead of a pilot light.
• With electric cook tops, there are a number of new types of burners on the market: solid disk elements, radiant elements under glass, halogen elements and induction elements. Solid disk elements and radiant elements under glass are easier to clean, they take longer to heat up, and they use more electricity. Halogen elements and induction elements are more efficient than conventional electric coil elements. Induction elements require that you use only iron cookware (not aluminum).
• The range hood should ventilate to the outside and not simply re-circulate and filter the cooking fumes. This is especially important with gas ranges. Be careful with the size of the fans - too large a fan can waste energy and cause back-drafting of combustion gases into the house. This is a major concern with large downdraft ventilation fans used with some cook-tops and ranges. Ask about make-up air ducts available for these models.

1. The efficiency of a dishwasher is measured by a term called the energy factor, which is similar to the miles per gallon for a car, but in this case is measured in cycles per kilowatt-hour of electricity. About 80% of the total energy used by dishwashers goes towards heating the water, so the best way to improve the efficiency of a dishwasher is to reduce the amount of water needed to clean the dishes.
2. Energy-saving tips:
• Don't pre-rinse dishes before putting them in the dishwasher. Scrape off food and empty liquids. Soaking or prewashing is generally recommended in cases of burned-on or dried-on food. If you must rinse dishes, use cold water.
• Clean the filter at the bottom of your dishwasher (make sure it is not clogged with food) regularly to keep the machine running efficiently.
• If the dishwasher has a "sani" setting or booster heater, reduce the temperature on the hot water tank to about 120°F. This will significantly reduce overall water heating costs.
• Load dishwashers to capacity before running them.
3. Purchasing tips:
• Using EnergyGuide labels can save you money; also look for the ENERGY STAR® label, which indicates that the dishwasher is energy efficient.
• Purchase dishwashers that allow you to choose between heat-drying and air-drying. Heat-drying elements draw considerable electricity; circulation fans for air-drying use very little.