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How to ManageEnergy Costs Effectively

Energy management used to be straightforward in the past. For example, food manufacturers simply received a bill and paid it. But today, there is a different scenario.

It's no longer an option. It's a strategic business necessity!

By Al Hamdan
AC drives are instrumental to increasing energy efficiency.
Energy management used to be straightforward in the past. For example, food manufacturers simply received a bill and paid it. But today, there is a different scenario. Increased competitive pressures, tighter margins and rising energy costs are forcing food producers to alter their methods of operation. At the same time, new ways of managing energy consumption and quality through sophisticated power monitoring tools have emerged, providing the information that companies need to implement a more energy-efficient operation. In short, effective energy management is no longer an option; it's a strategic business necessity. The key to effective energy management is information and knowledge — information on what's happening and the knowledge to do something about it. More specifically, it's understanding where, when, and how much energy is being consumed and having the ability to act. Finding the hidden energy costs can be a source of substantial savings for food manufacturers if they know where to look. By developing an integrated energy management program based on accurate consumption and spending patterns and demand profiles, companies can calculate power consumption costs among various production lines or in the manufacturing of a specific product. With a more accurate determination of actual production costs, managers can make more intelligent business decisions. An important element of an effective energy management strategy is working with an energy management expert who understands industrial processes and knows how to uncover energy-saving opportunities. Without a competent partner in the field of automation and power management to provide guidance through the selection and implementation process, companies can end up with the wrong type of power monitoring hardware — a mistake that could wipe out the savings an energy management solution is intended to provide. Automation and energy experts can play a key role in helping food manufacturers understand their tariff structure and how energy bills are calculated. They also can take the energy information and develop a plan to reduce energy costs.

What to Do First

Before implementing the required energy management technology and underlying infrastructure, companies should first identify their overall business goals, then develop an energy strategy that seeks to accomplish those goals. The goals should be specific to the areas of energy costs that need to be addressed. For example, are electricity costs the primary concern or does the strategy also need to consider consumption patterns related to water, air, gas, and steam? Does the company have a specific cost reduction goal in mind? In many cases, the first step for a plant may be to simply understand where and how much energy it is consuming. Then, once those questions are answered, companies can be in a better position to formulate more specific cost reduction or efficiency objectives. Energy management goals typically can be divided into two segments: 1) consumption or how efficiently you are running your processes and 2) power quality or how healthy your power is and whether or not the quality is affecting production equipment and shortening life spans. Once the goals are identified and the energy strategy is determined, the next step is to put the technology and infrastructure in place to achieve the desired goals. The good news is that while electricity is often the largest energy cost for most food plants, it can also offer the greatest opportunities for savings. Moreover, compared to other cost cutting initiatives, energy management efforts often deliver the fastest payback.

Creating the Infrastructure

Step One: Identify. In the food industry, approximately half of all energy consumption is used to change raw materials into products, while the remaining is used in food preservation and safety processes such as freezing, drying, refrigeration, and packaging. To better control and manage energy consumption, you first need to be able to measure it. Once the underlying infrastructure is in place to understand where and how energy is being consumed, it will be easier to formulate a strategy that will allow you to transition into the three core steps of energy management: monitor, analyze, and control. At the core of an effective monitoring program is a network of digital power monitoring devices that capture and communicate power consumption information. This allows plant managers to gather detailed information on power consumption in different areas of their plants on specific machines (such as refrigeration compressors) and even on individual production lines. Common monitoring system functions include the following: • Load profiling, in which desired power parameters and energy data are measured and transmitted by the power monitors. • Cost allocation, which is similar to load profiling, with added functionality that enables users to allocate energy costs to a department, process, or facility. • Distribution system monitoring, which gives a centralized view of the entire facility's power distribution system. • Power quality monitoring, which can be used to pinpoint failures of motors, drives, and sensitive equipment, negotiate better service from the utility, and identify the need for power factor correction and harmonic filters. Step Two: Analyze. While monitoring systems provide the foundation for the accurate collection and charting of energy data, analyzing this information enables plants to make better decisions about controlling costs. However, in order for this information to make a difference in operations, it must flow smoothly from the plant floor to the top floor. Therefore, the key to maximizing the benefits of an energy management program is coordinating the combination of power monitoring and control devices and the communication networks and visualization technologies into a unified system. At the heart of this arrangement is an integrated architecture based on open standards that allows users to deliver energy information to wherever they need it in the enterprise. An important requirement of this architecture is the ability to leverage existing networks and devices including a variety of product brands. Step Three: Control. After analyzing the data, plants can develop an action plan and install automation systems to capture energy savings using a number of control system options. Demand management systems, for example, automatically project future demand to ensure that the peak limit is not exceeded. Load management systems can monitor the electrical consumption of selected equipment and turn them on and off in an operator-selected sequence to minimize peak demand. Loads are prioritized to allow the user to configure the order in which loads should be shed and restored. Emergency load shedding systems reduce the total plant load automatically to keep key plant processes operating on the reaming in capacity in the event of a utility or generator loss. These systems constantly observe power system topology and evaluate what loads would be shed if a source was lost. Generator control systems deliver integrated power generation control such as starting, stopping, and synchronization of generators. While food manufacturers have large energy demands, they also have large opportunities for savings. Technologies and expertise are available that allow manufacturers to take control of their energy costs and protect their business from energy market fluctuations. The bottom line is energy costs are controllable. The key is identifying your energy management goals, developing a corresponding strategy, and putting the technology in place that enables you to accurately monitor, analyze, and control energy consumption and quality. Al Hamdan is with Power & Energy Management Solutions, Rockwell Automation. Headquartered in Milwaukee, WI, Rockwell Automation has customers in more than 80 countries and 21,000 employees. Rockwell provides industry and application solutions for demanding manufacturing environments. More information is available at www.rockwellautomation.com/index.html.