It takes the right kind of soil/moisture for good thermal contact, and it can take a very large (length and/or depth) group loop for something like an office bu

It takes the right kind of soil/moisture for good thermal contact, and it can take a very large (length and/or depth) group loop for something like an office building. There are limits to the technology. Skyscrapers are simply too large for any reasonable number of wells to provide adequate heating and cooling, Mr. Orio said. And it would be very difficult to install a well beneath an existing structure. http://www.nytimes.com/1997/04/20/nyregion/new-building-will-use-a-geothermal-energy-system.html?mcubz=0 http://www.nytimes.com/1997/04/20/nyregion/new-building-will...