Energy Management Best Practices for Food Processors
In the food processing industry, energy is most concentrated in both the cooking and freezing processes. By integrating innovative—as well as common sense— energy management best practices into your food processing facility, you can reduce your energy costs by 3 to 10 percent annually. Plus, improving the energy optimization comes with an enticing byproduct: reduced waste and emissions, two items with big price tags. Here are some energy management best practices for making your oven and freezer systems optimized.
The Oven Stage
The oven stage is hands-down the most energy-intensive part of the cooking process. Ovens use 10 percent of a facility’s total energy, so practices, equipment, and technology that can reduce oven time will have a big impact on energy consumption. Infrared ovens, which cut baking time and lower emissions, are slowly being adopted by the food processing industry. These kinds of ovens use ceramic coils or plates heated by flames to transmit infrared energy, which comes with the added benefit of no wasted heat dissipated into the surrounding air. Because large volumes of air do not have to be heated, infrared ovens can be 50 to 80 percent more efficient than convection ovens.
Other innovative energy management best practices in terms of oven type is the radio frequency oven. While still not in widespread use in the United States, these ovens contain a section that exposes the product to an electronic field that produces energy waves that pass through the air, alternating at frequencies around 40 million Hz. The water molecules in the product, activated by the waves, spin and create friction. The friction heats the product where the water is, resulting in a very targeted and controllable baking process. These ovens work particularly well in facilities that produce products with low water content, such as cookies and crackers.
In general, careful maintenance, control, and operation of an oven can greatly improve the overall energy efficiency of a facility. While large, direct energy efficiency savings can be found in improving the efficiencies of technologies such as motors and equipment insulation, indirect benefits can be realized by improving oven and dryer design, enhancing production throughput, decreasing downtime and optimizing production processes. Something as straightforward as calibrating oven temps for shorter startup times, for example, can have a surprising reduction in energy costs.
The Freezing Stage
One of the most innovative technologies starting to be used in the freezing segment of the industry is advanced phase-change materials (PCMs). Traditionally used to control thermal loads in commercial buildings, PCMs typically consists of a salt mixture filled into plastic containers and submerged in a tank of water, glycol or other liquid that readily transfers heat. Via a heat exchanger, this heat transfer fluid is then connected to a thermal source such as a boiler or chiller. The PCMs absorb or release thermal energy based on their temperatures and the temperature of the fluid.
In food procession facilities, PCMs can cut costs and decrease cooling loads resulting in excess chiller capacity. A facility with intermittent refrigeration loads can store this cooling energy during nonpeak load times to be released during peak load times throughout production.
The critical benefit? A more stable refrigeration load and fewer burdens on a plant’s freezing or cooling system. PCMs also can be beneficial for plants that have undersized refrigeration equipment, as PCMs can give facilities the flexibility they need to handle peak demand. Enabling facilities to run refrigeration systems at night when electricity rates are cheaper is a smart approach to handling peak loads and rising rates.