Eco-Friendly Geothermal On Tap
GRAND RAPIDS — With Kent County adding a geothermal system to its plan for the new 63rd District courthouse, it will use one system to provide both heating and cooling to the building.
Key to the system is a ground-source heat pump buried beneath the property’s frost line, which should be at least four feet below the ground’s surface, where the air is a constant 50 degrees. A heat pump is connected to a series of underground pipes and transfers the warmer air from underground into a building during the winter and does just the opposite in the summer.
A mixture of water and liquid antifreeze is circulated through the piping system. As that liquid moves through the pipes during winter months, it absorbs heat from the earth. When the liquid reaches the heat exchanger, it gets converted into warm air and is circulated through a building. The process is reversed during warm months by simply flipping a switch.
The ground-source heat is naturally renewable, non-polluting and free. No natural resources are wasted. The liquid antifreeze is non-toxic and biodegradable. There are no room-to-room fluctuations in temperature and no danger of carbon monoxide poisoning.
A geothermal system can last for up to 50 years, with most carrying warranties of 25 years. The county will use electricity to run the system’s motors, but not to cool or heat the courthouse. The county expects the system will reduce the building’s annual cost for natural gas and electricity by more than 30 percent.