How to monitor and analyze energy costs in an industrial automation application. Includes strategies for uncovering and avoiding costly spikes that exceed utilities’ maximum allowable demand.
According to Nobel-winning writer (and co-founder of the London School of Economics) George Bernard Shaw, the only man he knew who behaved sensibly was his tailor. “He takes my measurements each time he sees me,” he said. “The rest go on with their old measurements and expect me to fit them.”
Shaw’s point was the need to know things in their ongoing state, an important consideration for companies looking to devise and implement better energy policies. “The first thing you need to understand is where your energy usage is,” says Ingo Magura, energy management marketing manager at Siemens Industry. “Without measuring, you cannot control anything.”
A number of factors have caused companies to implement more sustainable energy practices:
- Increased media attention to “green” issues, especially the impact of energy usage, with cover stories in Fortune, Business Week, and The Economist
- High-profile legislation, including the Kyoto protocol requiring global reduction in CO2 levels
- Key corporate initiatives, such as WalMart’s packaging scorecard, which is aimed at rewarding sustainable packaging and improving the use of the cube (i.e., square footage)
- Consumer pressure and preferences: the rising green market sector that includes everything from household goods to automobiles
- The emergence of green financial market metrics, such as the Dow Jones’ Sustainability Index and the FTSE4Good
- The proliferation of internationally recognized standards
- The rising costs and increasing scarcity of energy sources, particularly petroleum-based commodities
“All these trends impact how businesses think about energy and sustainability,” says Magura.
Corporate options to these pressures include passing along costs to customers, reducing profit margins, and looking for energy efficiencies within their own organizations. “Energy management as a practice has gathered momentum because of this environment,” notes Magura. “It’s a necessary process in sustainability programs that help address the most commonly asked questions: How can I remain competitive despite increasing energy costs? How can I save energy costs? How can I reduce carbon emissions?”
What to Do
Companies must first identify their energy flows. Typically, that means implementing an energy management monitoring system that measures electrical energy. Power monitoring devices that are capable of communications are used. Strategic areas are identified in the manufacturer’s electrical distribution system, and from those areas data is captured, logged, trended, and archived. Data is analyzed to determine how much energy is being used and where.
Once it is determined how much energy is being used, the next step is to evaluate how it is being used. “You may find some strange or peculiar things at this point,” says Magura. “What caused that electricity spike at 10 a.m. Monday morning? It may be that maintenance personnel fired up all the backup pumps for a part of the process, as they do every Monday morning. By doing so, they exceeded the maximum demand for the facility.”
Exceeding maximum demand is very costly. Utilities will penalize a user heavily for this. For a plant, this could mean a loss of revenue or profits for a month. “Or when you examine your data, you may see that while production lines A and B are identical and running the same speed, production line B is using much more energy,” Magura continues. “When you drill deeper, you may find that a specific motor on line B is the cause.”
Analysis of the data will yield a more granular picture of how energy is being used—the proper measurements, to use Shaw’s analogy—allowing adjustments to be made to better fit your production to energy rates, be it by replacing or adjusting a part (in the case of the motor) or shifting times of testing backup pumps to avoid penalties.
Dancing the Three-Step
Siemens Industrial recommends that its customers become more energy efficient as part of a continuous improvement process encompassing three steps:
The first step is described in detail above: identify energy flows to discover your hidden energy potential. Second, evaluate the savings potential. Consider the lifecycle costs of your investments. Finally, implement efficiency measures to improve your machines and processes.
The Final Bow: Communicate Your Success
Completing the three process steps should lead to energy savings and more sustainable practices, but for the long-term energy management plan to succeed, it’s necessary to measure success and communicate energy efficiencies to stakeholders. Their buy-in will prove essential. “Any energy management strategy or program that does not have a decent communications channel will very likely die,” says Magura. “Sooner or later, if the results are not being communicated, no one knows how successful the efforts have been.”
According to Magura, a system is needed that generates daily, weekly, or monthly efficiency reports automatically and reliably. These reports should be generated for multiple sites and Web-accessible to anyone in the company. Further, energy accounting data should be automatically passed to higher-level systems such as ERP.
“This is energy data management at the highest level,” concludes Magura. “We are introducing a segment-independent, platform-independent product that can interface with any subsystem to extract vital information—energy usage in any form—to create KPIs calculated for whatever values required, then put them into clear, concise reports for management. It’s called Simatic B Data, and I believe it will be a tremendous contributor to sustainability efforts in the industrial segment.”
Watch for a detailed discussion of the Simatic B Data product in a future issue of Totally Integrated Automation.Have an Inquiry for Siemens about this article? Click Here >>