- Significant savings can be found in ENERGY STAR-qualified appliances.
- The Fisher-Nickel Food Service Technology Center (FSTC) offers life cycle cost calculators for various cooking equipment.
- The use of hot-food-holding cabinets is another cooking technique that can reduce overall energy use.
Electric cooking appliances are generally very efficient, though the following suggestions may help to further reduce energy costs.
- Upgrade equipment or change operating procedures to reduce energy costs. Significant savings can be found in ENERGY STAR-qualified appliances.
- Under part-load operation, electric fryers and griddles have proven more energy efficient than gas fryers and griddles. Under idle conditions, the energy consumed by a gas unit may exceed that of an electric unit by a factor of three or more.
- Use TRIAC controls for regulation of energy. The TRIAC is a three-terminal device that controls and conducts current flow to ensure that the proper amount of power is being used.
- Flat ribbon, low-watt-density heating elements consume less energy and have longer lives than traditional round calrod heating elements.
- Add insulation or upgrade insulation for electric units. Improved compartment insulation on steamers and kettles reduces heat loss to the kitchen and standby energy consumption.
- Incorporate demand ventilation, which modulates the range hood and makeup air fan speeds using infrared sensors and variable speed motors. A case study has shown a 60% decrease in demand (kW) and energy (kWh) consumption, as well as an equivalent savings in heating of outdoor makeup air using this technology.
- Use energy-efficient exhaust hoods that use outside air rather than inside conditioned air for ventilation.
- Side curtains around cooking equipment can help restrict the flow of conditioned air to the outside.
An ENERGY-STAR-qualified electric open-deep fat fryer must meet a minimum cooking efficiency of 80%, and also meet a maximum idle energy rate of 1,000 watts. In addition to shorter cooking times, a commercial restaurant may be able to increase production throughput with more energy-efficient appliances. The user may also want to consider frypot insulation to further reduce standby losses and to lower the idle energy rate. The Fisher-Nickel Food Service Technology Center (FSTC) offers life cycle cost calculators, including one for electric fryers.
The use of hot-food-holding cabinets is another cooking technique that can reduce overall energy use. An ENERGY STAR unit must meet a maximum idle energy rate of 40 watts/cubic foot, and is generally 50% to 60% more energy efficient than standard models. Models that meet this requirement incorporate better insulation, which reduces heat loss, and may also offer additional energy-saving devices such as magnetic door gaskets, auto-door closures, or dutch doors. The insulation of the cabinet also offers better temperature uniformity within the cabinet from top to bottom. FSTC’s hot-food-holding cabinet cost calculator provides a means to compare various designs.
Electric steam cookers can also achieve ENERGY STAR ratings if they meet a minimum cooking efficiency of 50% while also meeting maximum idle energy rates. Idle energy rates are specified for 3-, 4-, 5-, and 6-pan sizes. These more efficient units use considerably less water (in some cases almost 90% less—from 25 gallons per hour down to 3 gallons per hour for the top rated units). This lower water use can add up in a busy commercial cooking establishment, and will also lower the facility’s water utility bills. The FSTC offers an electric steamer life cycle cost calculator on its Web site.
A commercial kitchen will also include refrigeration equipment. Where possible, the end user should select the more energy-efficient solid door, as well as reach-in refrigerators and freezers that are designed with components such as Electronically Commutated Motor (ECM) evaporator and condenser fan motors, hot gas anti-sweat heaters, or high-efficiency compressors, all of which will significantly reduce energy consumption and utility bills. Compared to standard models, ENERGY-STAR-labeled commercial solid door refrigerators and freezers can be 40% to 50% more energy efficient compared to standard models. FSTC also provides a helpful cost calculator on refrigerators so that the restaurant owners can do their own analysis.
|Comparison of Energy Consumption for Gas & Electric Cooking Appliances|
|Capacity||Operating Hours per Day (h/d)||Duty Cycle (%)||Annual Energy (kBtu)||Duty Cycle (%)||Annual Energy (kBtu)||Annual Energy (kWh)|
|Open Deep Fat||35-50 lb||12||20%||74,900||20%||38,300||11,200|
|Flat Bottom – Chicken/Fish||125 lb.||10||30%||168,000||20%||53,200||15,600|
|Flat Bottom – Donut||80 lb||8||20%||34,900||14%||17,000||4,985|
|Range Top||6 Burner||12||20%||120,000||25%||38,300||11,200|
|Chinese Range||2 Wok||10||30%||187,000||–||–||–|
|Standard||38 X 38||8||35%||62,400||25%||42,600||12,500|
|Kettles, Steam||60 Gal.||4||40%||62,400||40%||34,000||9,980|
|Braising Pan||30 Gal.||4||45%||49,900||60%||29,800||8,730|
|Source: Commercial Kitchen Appliance Technology Assessment, Food Service Technology Center, 2002|