Rendering of what Sherman Hospital and the lake will look like when the project is completed.

ELGIN, Ill. - Mechanical Inc. has a solid track record of successful hospital and green building projects, and that combination made them the mechanical contractor of choice for Sherman Hospital’s $310 million replacement hospital. Scheduled to open in late 2009, the hospital will be mainly heated and cooled by geothermal energy from a 15-acre artificial lake next to the facility.

“The geothermal lake was a wise choice, both economically and ecologically,” said Brian Helm, president of Mechanical Inc., located in Freeport, Ill. “The lake is projected to decrease Sherman’s gas and electric costs by nearly $1 million annually.”

Helm added that Mechanical Inc. is installing the hospital’s intricate heating and cooling system, including 275,000 feet of 2-inch piping in the geothermal heat exchanger - a component that uses the lake’s natural geothermal properties to heat and cool the hospital. The company is also installing the medical gas piping and the plumbing in the facility. Mechanical Inc. is working with Walsh Construction Co., the construction manager for the replacement hospital. Project executive Larry Voss is overseeing the project.

“Sherman Hospital will be the first hospital in Illinois to build a geothermal lake,” said Selena Worster of Mechanical Inc., project manager for the geothermal lake. “This lake will also be the largest of its kind in the nation.”


According to Worster, solar energy is absorbed by the surface layer of the 17-foot-deep geothermal lake, resulting in a natural thermocline and a relatively consistent temperature at the bottom of the lake. The lake will have a natural clay liner and be filled with rainwater. Water and methanol-bearing coils of piping, or heat exchanger rafts, are stationed at the lake’s floor. The steady temperature at the bottom of the lake will be the heating and cooling source for the solution passing through the coils. This solution, in turn, is circulated by a lake loop heat-pump system.

When the circulating solution reaches the water-source heat pumps, the energy is converted to warm or cool air to regulate the temperature of the majority of the hospital’s rooms. The emergency room and surgical suites will employ a traditional heating and cooling system, since they require cooler temperatures.


Worster brings considerable training and expertise to her role as project manager for the Sherman Hospital geothermal lake. She has a master’s degree in civil engineering from the University of Illinois, is a U.S. Green Building Council (USGBC) Leadership in Energy and Environmental Design (LEED) accredited professional, and holds a Green Contractor certification from the city of Chicago. She is co-chair of the USGBC Chicago Chapter’s State and Local Government Committee, and a member of the green building steering committee for the Mechanical Contractors Association (MCA) of Chicago.

Selena advises businesses to do their homework when selecting a contractor for a green building project. “You should request proof that the company is involved with the green building movement,” she said. “The contractor should be actively pursuing green projects and have LEED-accredited professionals on their staff. You should review their past green projects and find out if they are performing well as energy-efficient buildings.”

Worster sees this project as the beginning of a greener future for the Midwest, and ultimately, the nation. “More and more businesses are embracing green building,” she said. “Hopefully this project will inspire other businesses to pursue their own green solutions.”

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Publication Date:06/30/2008