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Elgin Community College

"Energy is neither created nor destroyed?it simply changes to another form". This is perhaps one of the most fundamental laws of physics and the simplest way of describing cogeneration. Elgin Community College, located in Elgin, Illinois, has put cogeneration to the test. And the results are in. Cogeneration receives an A+.

Built in the early 70s, Elgin Community College has grown to include its present total of 11 buildings on the main campus and one building at the Fountain Square Campus located in downtown Elgin, for a total area size of 726,000 square feet. Dedicated to the improvement of its students' lives through education, Elgin Community College offers a vast array of classes to the student body. But perhaps the most unique quality of the campus is the fact that over 75% percent of the power used by the college is produced by their cogeneration system.

What is cogeneration? Simply defined, cogeneration is the process of generating electricity and at the same time making use of the excess heat normally wasted during this operation. This heat has a wide range of applications and, in the case of Elgin Community College, is used for building cooling operations in summer and heating in winter.

As the college continued to expand questions were raised as to the most economical way to achieve energy savings. Several issues were taken into consideration. First was the issue of reliability. By generating their own power Elgin Community College has almost eliminated any threat to the campus from brownouts or total blackouts due to energy shortages. This allows them greater reliability and ensures that their campus will still be functioning during energy shortages. Although the decision to go cogeneration had been made many years before, it wasn't until 1996 that the idea was actually implemented. Results were immediate. With a 3-1/2 year payback on a project totaling $2-1/2 million, the college realized average monthly savings of approximately $30,000. Thus, the second factor in deciding for or against cogeneration; it is simply more cost efficient. And finally, the engineering department is in control. Having the authority to determine when and how these units will be used - for primary power, peak shaving, or emergency power - allows more versatility on the part of the operators to achieve maximum efficiency.

Chief Engineer, Calvin Byrd, has been with Elgin Community College for the past eight years. Officially carrying the title of Manager of Plant Operations and Custodial Services, it is his job to keep the campus running. Under the direction of Paul Dawson, Managing Director of Facilities, Calvin supervises a total of 77 employees in the engineering and custodial departments. His foreman, Ed Cook, and two first and two second shift engineers operate the building from 6 am to 11 pm, six days a week.

Attending Waukeshaw training classes, Cal and Ed learned the theory and operation of the four Waukeshaw 5108GL engines. Weighing in at approximately 36,000 pounds each, it took two cranes to put the engines in place in the plant. Drawing 770 kilowatts of power from each engine, over 3,000 kilowatts of power can be generated when all four engines are running. Although ComEd maintains a permanent feed, Elgin Community College only imports between 20 and 50 kW from them. In the unlikely event that the engines should fail an automatic breaker will trip and the college can then import 100% power until repairs are made. Elgin Community College has contracted Charles Equipment Company to handle all major repairs. The engines will generate 4,160 volts of electricity and then send it to a transformer where it is stepped up to 12,470 volts. From there it will meet with ComEd's feed, draw the power needed, and make its way to each individual building transformer via switchgear located in the parking lot. Because they are working with electricity at such high voltages, both Cal and Ed also attended ComEd safety training classes.

Should power sources fail, three small emergency generators stand ready to supply enough power for a "black start" in the cogen plant. Once power fails, the system is set to automatically page Cal and alert him to conditions. Once on the property the engineers will shut all systems down, use the generators for enough power to supply the control panels, start the engines and restore power. Just one more assurance that Elgin Community College will not be in the dark like all the other businesses during a power outage.

In addition to providing boiler water to cool the engines, three Kewanee boilers are in place in the event cogen cannot produce enough steam to carry the load. As more water is needed to keep the engines cool, pumps located on the boiler feedtank replenish it. Because the engines are constantly making steam, something needed to be done with the excess load if no steam was called for. "Dummy" heat exchangers were set up to handle this. The excess steam is diverted into these heat exchangers where it is cooled using glycol. The heat is then released through radiators on the rooftop. In this way the steam process never comes to a complete halt. In addition to being cooled by water, these engines are also protected from overheating through the use of air. A constant airflow in the engine room is critical to their operation and maintained through the use of three round exhaust fans. As an auxiliary means of cooling, each engine has a cooling loop. The loop cools the air from the turbo before it enters the carburetor.

As with all engines, oil is a necessary component to keep them functioning. Each Waukeshaw engine holds approximately 80 gallons of oil. An excess oil tank is located on the back of each engine for in-between oil changes to ensure that they never run out of oil. In the event this should happen, a float switch automatically shuts the engine off until an adequate oil level is achieved. Complete oil changes can be accomplished with the turning of valves set up for this purpose. Two 500-gallon oil tanks, one for new oil and one for used oil, were designed by Boncosky Oil to function with this system. Oil is changed every 10 weeks or 720 hours by pumps, removing the old and replacing it with the new. While this process is actually very quick, a complete PM might take as much as 24 hours to complete. As the used oil tank is filled, a contracted oil waste hauler will empty and dispose of it.

During the process of producing needed electricity the exhaust gas from the engines is run through a thermal recovery package. Waste heat boiler tanks located in front of the engines store water to be used in the steam process. The waste heat is transferred to the water via tubes thereby producing steam. Sent through the main header via a one-way check valve, the steam is used for three purposes: chilled water through an absorbtion chiller, heat exchangers and instantaneous domestic hot water.

At one time a 12,000-gallon water tank was located on the premises for domestic water. It has since been removed in favor of a smaller, more economical on-demand unit producing instantaneous hot water. Nine Patterson-Kelly high efficiency thermific hot water boilers are on the premises ready to take over if cogen cannot produce enough steam.

Chemicals provided by Water Environmental Technologies are automated through the Trane Summit System as is pump activation. This is a fairly unique situation and as such, Trane Chicago Services needed to customize their computer program. While it presented a challenge, it was one challenge Trane was equipped to handle.

Once the steam is produced, it is sent to a series of 5 converters representing a hot water loop for the heat exchangers. Two separate loops originating in the boiler room branch out in ceiling space to service the entire campus. Although a walk through the campus main building leaves you with the impression that this is one structure, the engineering staff looks at them as five separate buildings interconnected. This concept has been achieved through the years of expansion that the college has undergone, actually enabling the hot water loops to be broken down into separate systems to facilitate repairs in the event that a pumping problem should occur. Whether steam is produced via cogeneration or boilers, this low-pressure process is tied into the same system, piped into the same header and sent to the converters to heat the hot water loops.

Chilled water is obtained through a Trane 600-ton, 3-stage centrifugal chiller. Originally using R-11, the unit has been entirely reclaimed and upgraded to R-123 in response to EPA regulations. All starters and controls have also been upgraded to tie into the building management system. With computer consoles located in Cal's office, Ed's office, and in the cogen plant, all outside temperatures can be monitored as well as all equipment functions in order to determine the most efficient operation.

Elgin Community College started operation with 5 rooftop units used for cooling, controlled by a Tracer 100 system. As the college expanded, more units were added to bring the total to 28 rooftop units ranging in size from 15- to 50-ton, all now monitored with a Trane Summit System. With the Summit System upgrade Trane was presented with yet another challenge. The existing control systems were not compatible with the Summit. Trane determined they could remove the old controls without having to remove the units themselves. Trane added PCM, Programmable Control Modules, to the units and created their own control system. With this, they then rewrote the program making the controls compatible with the Summit System. Elgin now has perhaps the only set of unique controls known to be in existence. According to Ed, "this has been great. The PCM is capable of being customized to do what you want. I have programmed it to control chemical processes, parking lot lights and building lights. It really works great."

Chief Engineer Calvin Byrd started working with ARA service in St. Charles. Eventually he was asked to transfer. Not wanting to do so, Cal interviewed with the college and got the job. He has taken numerous classes in HVAC and relies upon his hands-on experience today. Cal has been married 20 years, has 2 children and likes to play golf and smoke cigars. Residing in Batavia, Illinois, he has a 20-minute commute to work.

Foreman Ed Cook has been with the college for the past 7 years. Drawing on his immense knowledge of the equipment located here, Ed has become a valuable part of the engineering force. Ed is married with one child and in his spare time he gives guitar lessons and teaches HVAC at the college.

So what's in store for the future for Elgin Community College? A whole lot. Thanks to voters in the surrounding communities, a $41 million referendum has recently passed to update the facility and keep teachers and students alike competitive in today's market. This referendum will cover 22 projects to be completed over the next 20 years. They include building 3 new facilities, remodeling 7 existing buildings, finishing 3 additions, adding 2000 more parking spaces and improving roads and utilities to accommodate the projected 50,000 student population by the year 2020. There is no doubt that Cal, Ed, and the rest of the engineering and custodial staff will have their work cut out for them. There is also no doubt they will do the best job possible.

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