More on Geothermal Energy
Geothermal heating and cooling uses the temperature just below the Earth's surface- which hovers between 42 and 55 degrees F - to control air temperature. It is a free, renewable and low-impact resource that offers a sustainable alternative to burning fossil fuels and other pollutants.
The Oswald Visitor Center, completed in 2005, is currently one of the largest public buildings in Minnesota using geothermal technology. A ground-source pump transfers heat into the Visitor Center in colder months via an environmentally-friendly, food-grade antifreeze solution that flows through 250 wells, each 200 feet deep, underneath the Arboretum's main parking lot. The wells are interconnected to form a closed-loop system, ensuring that ground-water pollution does not occur. In the summertime, heat from the Visitor Center is transferred to the ground in a reverse process using the same pump system.
Using geothermal energy as a means of climate control is as cost-effective as it is sustainable. According to the U.S. Environmental Protection Agency, geothermal exchange systems save between 30 and 70 percent in heating costs and 20 to 50 percent in cooling costs compared to conventional systems. For more information about geothermal heating and cooling, visit the official EPA website.