For a manufacturing plant just embarking on an energy efficiency program, a good first step is to contact your utilities providers to gain access to your site's energy usage. So suggests Lonnie Russell, production manager at AAI Corp.'s Charleston, S.C., operations. While his site has good power meters, Russell says the plant's electricity provider was able to give him visibility into his plant's power use on an hourly basis. "Get real data to measure your performance," he suggests.
"Understand where your power is going," echoes Dan Davis, AAI's director of operations. "Once you have a comprehensive understanding, you can start asking those questions: Why is that on? Why is that load there and does it have to be 24 hours a day? Can it be cut back and if it can, what are the parameters?"
Rockwell Automation's Doug Burns says that while the production footprint of many of his company's customers has evolved since the facilities were built, rarely has the facilities side of the equation kept up. As a result, "rarely is there a tight alignment between [energy] generation and what the production demands are," says Burns, practice lead, sustainable production, at the automation solution provider.
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Like AAI Corp., Rockwell Automation says that identifying your company's base power usage is crucial. "Otherwise it's hard to implement a remediation or corrective plan with goals," Burns says.
The automation firm suggests that audits be ongoing, both to review the status of previous projects and to look for additional opportunities. They should also take a team approach, involving representatives from each area that could be impacted by the audit.
Additional observations from Rockwell Automation include:
Look for ways to minimize energy usage at peak times of day. For example, Burns noted a customer that routinely -- and nearly simultaneously -- put the batteries that powered its forklifts on their chargers at the end of second shift, which caused a power surge at a peak time. Simply staggering the charging times helped the firm to avoid peak usage penalties.
Check out the air. "Air is the necessary evil to keep machines running, as well as electricity," Burns notes. Many industries use compressed air, yet it is not monitored very closely and typically systems can be laden with leaks. "Other areas that are traditional offenders are motors, fans, pumps, resistive heating and lighting," says Marcia Walker, Rockwell's program manager, sustainable production. "Those are generally relatively well-known to industrial customers in terms of knowing they might be an offender, but that doesn't mean they've necessarily done anything about fixing it yet."
Don't overlook the mechanical drive train. "People don't look at the mechanical drive train, primarily because it's mechanical and most people who look at electricity are electrical," Burns notes. "Also people don't realize that there is large efficiency variance between different types of gear reducers."
