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UIC Turns to Cogeneration

"If they can do it?so can we". Such were the thoughts of Utility Operations at The University of Illinois, Chicago, also known as UIC, when presented with the concept of cogeneration. And so begins their journey into the future.

Ken Buric, Director of Utility Operations, has been at UIC for 34 years. With the advent of cogeneration, his job function has changed.

The demand for more reliable utility production and distribution is not new. Recent energy crises in California and distribution problems in Chicago have brought energy demand issues to the forefront of many minds. Today's high-tech society has made utilities a non-negotiable entity. They must be supplied immediately upon demand. The question for many remains how to accomplish this at the most reliable and efficient level possible. UIC has found the way for them.
In 1987, Ken Buric, Director of Utility Operations at UIC, was approached with the idea of making the campus energy independent by building its own cogeneration plant on the premises. Promises of drastic energy savings enticed Ken to look into the concept a bit deeper. Following a feasibility study, Ken determined that if an outside company could provide savings such as this, why couldn't the University of Illinois accomplish the same thing, while at the same time achieving complete control over the process? The answer ? there was nothing stopping them. Plans were finalized, employees were trained, and cogeneration became a way into the future for the UIC campus.

Jay Hopman, Chief Plant Operating Engineer, East Campus, has been with UIC since 1980. His thorough knowledge of the equipment and its operation makes Ken's job a lot easier.

Cogeneration, the simultaneous production of heat and power in a single thermodynamic process, is not a new concept. Steam cogeneration was first seen as early as the 17th century. By the late 18th century, cogeneration had advanced to not only using steam, but also using waste steam to power engines and the use of hot condenser water for other purposes. Although great advances had been made, the bottom line still showed that only one-third of the fossil fuel being used to produce energy was actually being converted. The rest was being discarded at great cost. Further advances in cogeneration carried the process one step further. Instead of discarding the heat produced in this process, it was harnessed and used to provide space heating and hot water heating, thus eliminating the added expense of burning fuels for the sole purpose of space heating. In time, lower energy costs were finally being recognized by those using the cogeneration process. As the EPA advanced their regulations on air pollution emissions for major industrial plants, cogeneration helped lower the emission of carbon and sulphur dioxide pollutants into the air, thus making compliance to EPA rules obtainable. Added to those incentives came the current restructuring of the power generation and distribution industry making it more attractive for large businesses to produce their own power.

Stacks visible from the street are the only indication that the west campus stamplant and cogeneration facility are operating on campus.

Today, cogeneration is used throughout the world as a more efficient production process for heat and power. While the most common form of cogeneration can be found at utility generating plants, it is a concept that can be applied to any size structure, down to micro-cogen units supplying individual homes. Although cogeneration systems are more commonly seen in industrial plants, they are becoming more popular on college campuses where reliability and cost-efficiency are key factors in the operating budget. A case in point was a recent article published in The Chief Engineer regarding cogeneration at Elgin Community College in Elgin, Illinois.

A view from above one of the two Cooper-Bessemer, 20 cylinder, dual-fired reciprocating engines. These engines have added to the immense success of the cogeneration project.

Following suit, The University of Illinois, Chicago began their journey into cogeneration on the east campus in 1993. With the installation of two Cooper-Bessemer, 20 cylinder LSVB dual-fired reciprocating engines driving two Ideal Electric generators, each rated at 6.3 MW, the UIC Utility Operations Department could not foresee the immense success of their venture. Although operated almost exclusively on natural gas, the ability to run on #2 diesel fuel allows for added flexibility in determining the most efficient fuel to use. Currently the engines are started with diesel fuel, and then switched over to run on 99% gas, 1% diesel. Each engine is equipped with an oil system supplying 2,200 gallons of oil constantly being circulated through a series of main filters at 10 microns and a bypass filter at 2 microns. Because cold oil used on startup could destroy the filter system, the lubricating oil temperature is raised to an acceptable temperature before being circulated through the engines. Pumps located on the front of the engine maintain a constant flow of the 40-weight oil with special diesel additives being used.

The two larger engines in the picture are the Cooper-Bessemer's. The smaller engines at the rear of the photo are the Watsila 28's.

These 6.3 MW generators were capable of carrying the base load the east campus required. While originally supplying only electricity and hot water, the concept was such a success that the original 12.6 MW plant grew bigger with the addition of two Wartsila 18V-28SG natural gas reciprocating engines added seven years later. Driving two 3.8 MW ABB generators, the addition of these engines allowed the plant to pick up the seasonal cooling load being furnished by electrically driven centrifugal chillers in the central chilled water plant. The east campus had now become a 20.2 MW plant handling 3.8 million square feet of space in 20 campus buildings. We asked our tour guide, Jay Hopman, Chief Plant Operating Engineer, what convinced them to purchase the Wartsila engines the second time around. He answered that research had shown that the Wartsilas had a reputation for providing high electrical efficiency, offered dependable operation and a low maintenance cost. And so far they have proven to be true to their claims. Electricity is generated at 12kV and distributed to the individual buildings via a university owned distribution system. Electrical switchgear located in these buildings then steps down the electricity to 480V for use within the building.

Oil used to keep the engines cool reaches them through a complex maze of piping. Each piping system located in the engine area is color coded according to the job it performs.

Since the idea of cogeneration is to use every available unit of energy produced, four exhaust gas heat recovery systems work together to provide a total of 30MMBTU/h of recovered heat energy to offset heating and cooling requirements. To maintain emissions control, engine heat from the Wartsilas is routed through gas-fired afterburners first and then used for supplemental firing of the heat recovery boilers. These boilers then assist three hot water generators, which run on either natural gas or #6 fuel oil, in supplying water heated to a temperature of 400�F and distributed throughout the entire east campus through a series of underground pipes. This form of thermal energy further assists in heating and absorption air conditioning on the campus. Exhaust heat recovery from the Coopers is routed directly to heat recovery boilers. Jacket water heat is recovered from the Cooper-Bessemer engines and sold to St. Ignatius College Preparatory School and Holy Family Church for heating their facilities. Time and experience has shown both Jay and Ken that only three of the four engines are necessary to handle the winter base load. This load will vary between 10MW nighttime and 12-13MW daytime as people begin drawing power for their daily needs. The summer demands are different, however. Three York International electrical centrifugal chillers, for a total of 6,000 tons, and an additional 1,350 tons total of absorption chilling in individual buildings located throughout the campus, handle peak summer loads that will reach as much as 18MW daily. To assist with this, a Trane, 1,000-ton, two-stage absorption chiller was also added in the main plant.

Each engine is supplied with 2,200 gallons of 40 weight oil, that is constantly being circulated .

The success of the east campus facility was phenomenal. The initial east campus cogen plant was built at a total cost of $15 million. The payback goal was an estimated 10 years. Amazingly, that goal was achieved in 7.5 years with annual savings of close to $2 million. With the remaining money, further utility infrastructure repairs were made, and not a second thought was given to expansion of the plant.
Looking towards the west campus of UIC, a feasibility study was completed by Stanley Consultants, Inc. as to the best means of operation. The campus needed to take into account the existing steam plant in its plans for upgrading the system. Communications with the EPA told them that the east campus together with the west campus would be considered as one single source of emissions. Therefore, to facilitate obtaining the necessary permits for construction of the plant, four of the seven existing boilers were mothballed. Emissions credits from this decision enabled UIC to get the go-ahead from the EPA.

These pumps assist in recovering jacket water heat which is sold to St. Ignatious School.

The colossal success with the Wartsila engines on the east campus influenced the decision to install three natural gas Wartsila engines each rated at 5.4MW on the west side. Together with three natural gas Solar Taurus turbine generators, each rated at 7.0MW, three dual fired, natural gas/#6 fuel oil, boilers and three exhaust gas heat recovery steam generators, this rounds out the list of equipment necessary for producing the base load of 36MW of power produced at the west campus. However, foresight was used, and the capability of expansion to 45MW was built into the system with the eventual addition of more equipment. Once again, prudent decisions paid off.

A watsila 34 engine at work on the West Campus.

Although located approximately one mile apart, both campuses were designed to operate as one system. Connected by a 69,000V underground electrical line, energy can be moved from one side of the UIC campus to the other, according to need. The two plants combined give UIC a 57.4MW system covering 8 million square feet and serving over 27,000 students in both classroom and dormitory settings. Even though capable of producing all the power needed, the school is still connected to ComEd. In the event of an emergency, UIC has the option of turning off non-essential equipment, importing power from ComEd, and even selling their excess power back to ComEd. According to Jay, "If everything runs right, we are a totally independent operation".

This dual fuel, high temperature hot water generator is located on the East Campus.

In addition to the new equipment on the west campus, the control room was located there also. Run with advanced power management systems and redundant backup systems to ensure non-interrupted service, operators can determine which plant or combination of both is needed based on the load demand. A view of each engine and turbine as well as the chiller plants, steam plants, hi temp plants and distribution system can be seen from here. An overview of the entire electrical distribution system is also monitored. Installed by Novaspect, Elk Grove Village, Illinois, the Fischer-Rosemont, Delta V System is state-of-the-art, continuously monitoring conditions on the campus.

Heat recovery boiler pumps and pump seal coolers ensure every available bit of en energy is put to use.

Being overwhelmed at the amount of equipment needed to make this happen, we wondered what else the Utilities Operations Department handled, if anything. Ken told us we needed to keep this is mind: Utilities Operations at UIC is essentially a utility company. They are responsible for development of the plants, generation of the power, and distribution to each individual building. As such, they handle all construction projects related to the plants, including the bidding for projects, and so on down the line to completion. Each plant employs 18 plant operating engineers and a Chief and Assistant Engineer as well as other staff employees. Plant employees receive a large amount of training in four essential areas: the chillers, the high temp hot water system, the Cooper-Bessemer engines, and the Wartsila engines before being allowed to work on their own.

An overhead view of a Wartsila 28 engine shows the exhaust purge fan used on each of them.

Heading the list of top employees was our tour guide for the day, Jay Hopman, Chief Plant Operating Engineer on the east campus. Jay originally received his degree in Business Administration. With the job market at an all-time low after his graduation, he began working as an engineer. Employed at the Bismarck Hotel, and then Standard Oil, Jay has been at UIC since 1980. He thoroughly enjoys his job and commented that his current position was about as far away as one could get from where he started out.

This Solar Taurus 70 combustion turbine assists in the power generation on the West Campus.

Joe Motyka, Chief Plant Operating Engineer for the west campus, has been with UIC for a number of years. He was not available for the tour on the day of visit so Jay was gracious enough to show us around the west campus facility.

UIC is essentially its own utility company. This 69kV substation allows electricity to be moved from one campus to the other.

Ken Buric, Director of Utility Operations, has been employed at UIC for 34 years. Within that time, and with the advent of the cogeneration plants, Ken's job has changed. Campus utilities used to be a UIC campus function. Keeping in mind that the University of Illinois maintains three distinct campus locations, Chicago, Urbana and Springfield, reorganization brought about the formation of a central administration for all three locations. Ken now works in this central administration. He related that the reasoning behind this move was twofold. First, the drastic savings seen by the construction of the power plants could essentially be used for any project on any of the three campuses, rather than just at UIC. Secondly, savings could be recognized through combined purchases for all three areas rather than treating each area in a separate purchase. The joining of the three was a smart business move.

The Eas Campus has its own control room for monitioring of essential equipment.

Cogeneration?the wave of the future? Absolutely, in the eyes of the UIC staff. With the success of their two plants there can be no doubt that many more campuses will follow suit. UIC has assured its students and faculty that there is no possibility of being left in the dark.

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