Written by Michael Chimack
What does a University of Illinois undergrad, a printing company, and a malfunctioning air compressor all have in common? In most cases, nothing. If, however, they're involved in one of 26 Industrial Assessment Centers being funded by the U.S. Department of Energy, the answer is: plenty. These Centers are designed to provide graduate and undergraduate students with paid internships in practical energy conservation. In turn, qualified industrial manufacturers receive free energy management expertise targeted on two objectives: reducing energy consumption/waste/pollution and saving money.
The federal government also has a keen interest in reducing our dependence on foreign oil. As economic forecasts are pointing to dramatic increases in energy costs, manufacturers are seeking more aggressive cost-cutting strategies. Through these designated Industrial Assessment Centers (IACs), students serve as a bridge between the objectives of business and government.
At the University of Illinois, for example, nine students – under the supervision of Dr. William Worek, Center Director – conduct 30 energy assessments a year for small and medium sized manufacturing plants in Illinois and northwest Indiana. "We help industrial plant managers achieve a better understanding of the required energy use to manufacture their products," said Worek in a recent interview. "We supply them with recommendations on how to operate their equipment at peak efficiency and, in turn, boost their bottom line."
Industrial Assessment Centers have been in place since 1976, when the federal government launched four Centers as a component of the National Energy Strategy. According to the Department of Energy's web site, these Centers have been highly successful. In addition to the obvious benefits to the manufacturers in increased productivity and cost savings, this program trains, motivates and helps prepare students for careers in energy management. It also helps reduce industrial energy waste and pollution, and offers university faculty new insights to apply to their engineering curriculum. The assessments also provide valuable data and energy trends to the Department of Energy (currently available through the Center for Advanced Energy Systems at Rutgers University).
Recommendations from the industrial assessments have averaged about $55,000 in potential annual savings for each manufacturer, according to the Department of Energy.
To conduct energy audits and assessments, the University of Illinois relies on energy meters provided by DENT Instruments. "In the course of our assessments – of lighting systems, production equipment, electric chillers and compressed air systems – we have to determine peak electric demand and total energy used," said Worek. "We use DENT energy meters to help us understand how those pieces of equipment operate within a typical production day. Once we understand how they operate we can recommend changes that result in energy savings."
The IAC team determines how energy is being used throughout manufacturing plants. "DENT's meters allow us to track how air compressors cycle, or if lights are ON when they should be OFF, for example," said Worek. "If lighting systems are not functioning properly, that's a huge opportunity for savings. This intervention can save plants from hundreds to thousands of dollars a year, depending on the size of the plant."
Compressed air systems are another area audited by IAC team. "One of the most complicated systems to understand is air compressor systems," said Worek. "We monitor compressed air equipment with DENT power meters to determine how a compressor is operating. A meter will tell us, for instance, how the 'trim' compressor is loading in a multiple compressor system. The goals are to: A) understand how the system is controlled so we can understand annual operating cost of the compressed air system, B) address air system demand issues such as repairing leaks, insuring proper use of compressed air plant-wide, and C) determine the cost associated with those end uses. The ultimate goal is to shut off a compressor if possible. It's always the same endgame: conserve electricity, save money, and raise bottom line of the company."
The IAC team chooses DENT Instruments because they're extremely easy to use. They're compact, so we can bring a lot into the field without having to rent a truck to carry them. The software is also very user-friendly. The meters are robust in that they can measure electric demand directly, as well as power factor, volts and amps. We exclusively use the ELITEpro with high memory option and have converted most of our older loggers to high memory. We don't know what we'll need until we're in the field. Without the high memory option, we'd have to send manpower back into the field to download data, or risk losing data.
Recent energy audits at a manufacturing plant saved that particular company nearly $50,000 in the first year our recommendations were implemented.
The plant had a decentralized air compressor system – with multiple compressors of different horsepower located in various areas of the plant – feeding a common header. We monitored those systems to discover how the compressors were being controlled. What we ultimately discovered was that several compressors were fighting each other – cycling on and off frequently. That was causing two problems: 1) the cycling compressors were using energy but not necessarily supplying any air, and 2) that cycling frequency could affect the longevity of the compressors.
Once we used DENT's energy meters to understand the generation side of the compressed air system, we were able to understand which compressors were not contributing to the system as designed. Then we went into the plant and assessed the distribution side of the air system.
We recommended that they repair leaks and shut off local compressed air supplies to equipment that were either not being used or in SETUP mode. We also recommended that they replace compressed air use with high-volume, low-pressure blowers where applicable. The end result was a lower volume of required compressed air, thereby allowing for shutting off two compressors (150 HP total), which demonstrated savings of 750,000 kilowatt-hours, and nearly $50,000 dollars in less than one year.
New and emerging technology offers manufacturers– and the national IACs – tools with which to analyze energy consumption. With reliable data, literally "in hand," these meters and the accompanying software can add significantly to the bottom line of manufacturing companies, schools and universities, health facilities and corporations.