We just completed building a house in the country. Because I write for GEO Outlook, the trade publication of the International Ground Source Heat Pump Association (IGSHPA), I decided this was my opportunity to put my words into practice – plus the federal tax credit was a long-term financial incentive.
So, geothermal is our choice for our home heating and cooling – and so far, just like the theory and reports, it’s a joy! I’ve been in the house with its cathedral ceilings and lots of open space when the thermostat reads 64 degrees – and it’s comfortable! In my current house, a series of boxes joined by a hall, 64 degrees is the misery factor not only for me but everyone around me who has to listen to my complaining.
The design and orientation of the house supports the geo system – thanks to my architect husband. The house is an energy fortress with a metal roof, foam insulation, low-E windows and a stone and stucco exterior. There’s minimal opportunity for hot or cold air to enter. Its orientation captures the sun in the morning with shade in the afternoon. The one caveat I’ll claim is that winter 2012 in Oklahoma has been mild, so the sytem hasn’t had a test of its true potential.
Here are the basics of geothermal:
Ancient science to modern technology, geothermal heating and cooling systems provide eco-logical and eco-nomical solutions for sustainable living. The concept is simple: taking advantage of the earth’s constant temperature of 45 to 75 degrees Fahrenheit to cool and heat buildings.
Geothermal systems exchange heat with the earth by using an underground network of loops that circulate water or refrigerant. In the winter, this fluid pulls heat from the ground and transfers it to the building using a heat exchanger. An indoor fan system circulates air through the building. In the summer, the system operates in reverse by depositing heat from the house into the earth and bringing cool air back in. Ground source heat pump (GSHP) systems are versatile and can be installed in both new and existing construction. Retrofits can often use existing ductwork with minimal modifications.
Once a technology used mainly by government, businesses and schools, GSHPs are fast becoming the green technology for homeowners and builders. The US Department of Energy estimates about 50,000 homes install or add a GSHP each year.
Benefits of a GSHP System
~ Efficiency and eco-friendly – The system does not rely on fossil fuels. The EPA has named the systems “the most energy-efficient and environmentally sensitive of all space conditioning systems.”
~ Durability – Because the loops are underground, they are protected from external elements like weather and vandalism. Life-expectancy is 50 years or longer.
~ Low-cost operation - Operating costs are up to 60 percent less than conventional heating and cooling systems. Free or reduced hot water costs are an added benefit with some systems. With such savings, GSHP systems often pay for themselves in 3 to 5 years.
~ Comfort – Homeowners with GSHP systems report a consistent temperature, eliminating hot or cold spots in the ouse. The systems also maintain humidity at a constant comfort level. There are no outside compressors, which eliminates exterior noise.
Costs and Credits
Even with all the benefits of GSHPs, sticker shock for installation can keep homeowners and builders from using the technology. Installation is not a do–it-yourself weekend project. Costs can be several times higher than conventional systems with comparable heating and cooling capacities. Repairs to the system, although seldom, can be difficult and costly.
The American Recovery and Reinvestment Act of 2009 can help offset the upfront costs of a GSHP system. The federal tax credit allows a one-time 30 percent tax credit on a complete GSHP system,including installation. The GSHP must meet or exceed federal EnergyStar requirements. The tax credit expires in December 2016. Check with your accountant for required forms and information. Some states and utility companies also offer rebates and lower utility rates for GSHPs.
We’ll keep you in the loop with periodic updates on our geo experience!