EARTH ENERGY SYSTEMS, INC. - 51 Foley Street, Santa Rosa, CA 95401 - CA Lic. # 739840
Ph (707)523-4363  -  Fax (707)523-4360
info@earthenergysystems.com

Pond and lake loops are less-expensive to install than vertical or horizontal ground loops and work well for both residential and commercial buildings.  Instead of straight pipe, coils of polyethelene pipe are connected to each other and placed within 1 foot of the bottom of most ponds.

 
Courtesy of Geothermal Heat Pump Consortium, Inc.

The pond or lake must be at least 8 feet deep.  The surface area required is determined by the heating and cooling loads of the building being served.  

  Floating loops prior to sinking in an existing pond (click on image to enlarge)

  Loops in the bottom of a new pond before filling (click on image to enlarge)

  Pond after filling (click on image to enlarge)

A 5,000 square foot home might require eight 300-foot coils of pipe. 

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