There are copious amounts of water available year-round at a steady temperature of somewhere between 54 and 57 degrees (Fahrenheit) underneath the Southwest Eco-district. The payback period for installing geothermal heating and cooling has varied between 4 and 12 years in Silver Spring Md and New York City.
Nationally, one-sixth of our energy use is devoted to heating and cooling buildings. In 2009 about 35% of our energy was from petroleum, 23% from natural gas, 20% from coal, 8% nuclear and lesser amounts from biomass, hydro, wind, geothermal, and solar.
Explore transitioning to geothermal heating and cooling throughout the eco-district.
Here's a link to a video about two kinds of systems that are now tapping geothermal energy in Beijing: