Lake to heat, cool Elgin's Sherman Hospital
Long before gasoline topped $4 a gallon and "going green" became chic, Sherman Health officials made the environment and efficiency a priority.
Tuesday afternoon, hospital officials showcased a 15-acre geothermal lake -- the largest in the nation -- that will heat and cool the 225-bed facility under construction at Big Timber and Randall roads in Elgin.
The system will save an estimated $1 million a year in energy costs and ultimately contain about 150 miles of looped tubes at the bottom of an 18-foot-deep lake.
"It doesn't get any greener than this," said Warren Lloyd, vice president at the Rock Island-based KJWW Engineering Consultants, which designed Sherman's lake.
In the winter, the system and its geothermal heat pumps will pull the Earth's natural heat from the lake into the $310 million facility.
A mixture of water and non-toxic antifreeze circulates through the loop and carries the heat to the hospital.
Then an electric-powered compressor and a heat exchanger will concentrate the energy into heat that is later blown through vents just like a furnace.
But unlike a furnace, no natural gas is burned.
"The hospital is heating itself. That's a strange thing to say, but it's part of the energy savings," said Charles Burnidge, an Elgin architect and member of Sherman's board of directors.
Burnidge said Sherman officials explored and chose the geothermal option long before the first shovel was planted in June 2006.
Burnidge also noted all of the private rooms have a view of the nearby forest and lake, which will be surrounded by a walking path and stocked with fish.
In the summer, the system is reversed.
The loops draw excess heat from the building and allow it to be absorbed by the lake water. It's more efficient than a traditional air-conditioner.
The system cools in the same way that a refrigerator keeps food cool -- by drawing heat from the interior, not by blowing in cold air, said John Kelly, executive director Of the Washington, D.C.-based Geothermal Heat Pump Consortium Inc.
"People don't understand how the system works. It seems like magic, but it's really not," Kelly said.
Tuesday, crews in rafts installed a few of the nearly 2,500 loops in the lake.
This work will be completed in about six weeks; the hospital is slated to open in late 2009.
Christine Priester, Sherman spokeswoman, said students will be able to take field trips to learn how the geothermal lake works after the hospital is completed in late 2009.
"We have people calling (us) from all over the world. There's a hospital in Nigeria looking to take a tour because they're thinking about this as well," she said.