Geothermal heat exchange system for water supply

Abstract

The geothermal heat exchange system for a water supply is an open system, i.e., water flows into the system for consumption and use and is then drained from the system, as opposed to a closed system where the water is recycled through the system. The present system receives water from an elevated source, e.g., a hilltop tank or an elevated community water supply tank, through a relatively large diameter pipe. The water is then delivered to a subsurface pipe system of one or more relatively small diameter pipes for more efficient thermal exchange. The subsurface pipes are preferably manufactured of material having relatively high thermal conductivity. The subsurface pipe system is preferably buried at an intermediate depth between the surface and the depth where constant temperature occurs in order to provide most of the benefits of a subsurface system while reducing the labor required to bury the pipe system.

I claim: 
     
         1 . A geothermal heat exchange system for a water supply, comprising:
 an elevated water supply providing a pressure head;   a large diameter water supply pipe extending downward from the elevated water supply;   at least one subsurface water pipe disposed below the level of the large diameter water supply pipe, the subsurface water pipe communicating fluidly with the large diameter water supply pipe, the subsurface water pipe being formed of material having a high thermal conductivity;   a dispensing fixture water supply pipe communicating fluidly with the at least one subsurface water pipe, the dispensing fixture water supply pipe extending upwardly from the subsurface water pipe to a point above ground level and below the elevated water supply;   a dispensing fixture disposed above ground level, the dispensing fixture selectively receiving water from the dispensing fixture water supply pipe; and   a wastewater drain extending from the dispensing fixture.   
     
     
         2 . The geothermal heat exchange system for a water supply according to  claim 1 , wherein:
 the subsurface water pipe has a smaller diameter than the large diameter water supply pipe; and   the dispensing fixture water pipe has a smaller diameter than the large diameter water supply pipe.   
     
     
         3 . The geothermal heat exchange system for a water supply according to  claim 1 , wherein the subsurface water pipe is buried at an intermediate depth between ground level and a level of constant temperature below ground level. 
     
     
         4 . The geothermal heat exchange system for a water supply according to  claim 1 , wherein the at least one subsurface water pipe comprises a plurality of small diameter parallel pipes. 
     
     
         5 . The geothermal heat exchange system for a water supply according to  claim 1 , wherein the at least one subsurface water pipe comprises a single small diameter pipe having a sinusoidal path. 
     
     
         6 . The geothermal heat exchange system for a water supply according to  claim 1 , wherein the large diameter water supply pipe has a diameter of about two and two-thirds the diameter of the subsurface water pipe. 
     
     
         7 . The geothermal heat exchange system for a water supply according to  claim 1 , wherein the dispensing fixture is a washbasin. 
     
     
         8 . A geothermal heat exchange system for a water supply, comprising:
 an elevated water supply providing a pressure head;   a large diameter water supply pipe extending downward from the elevated water supply;   at least one subsurface water pipe disposed below the level of the large diameter water supply pipe, the subsurface water pipe communicating fluidly with the large diameter water supply pipe, the subsurface water pipe having a smaller diameter than the large diameter water supply pipe;   a dispensing fixture water supply pipe communicating fluidly with the at least one subsurface water pipe, the dispensing fixture water supply pipe extending upward from the subsurface water pipe to a point above ground level and below the elevated water supply, the dispensing fixture water pipe having a smaller diameter than the large diameter water supply pipe;   a dispensing fixture disposed above ground level, the dispensing fixture selectively receiving water from the dispensing fixture water supply pipe; and   a wastewater drain extending from the dispensing fixture.   
     
     
         9 . The geothermal heat exchange system for a water supply according to  claim 8 , wherein the subsurface water pipe is formed of material having a high thermal conductivity. 
     
     
         10 . The geothermal heat exchange system for a water supply according to  claim 8 , wherein the subsurface water pipe is buried at an intermediate depth between ground level and a level of constant temperature below ground level. 
     
     
         11 . The geothermal heat exchange system for a water supply according to  claim 8 , wherein the at least one subsurface water pipe comprises a plurality of small diameter parallel pipes. 
     
     
         12 . The geothermal heat exchange system for a water supply according to  claim 8 , wherein the at least one subsurface water pipe comprises a single small diameter pipe having a sinusoidal path. 
     
     
         13 . The geothermal heat exchange system for a water supply according to  claim 8 , wherein the large diameter water supply pipe has a diameter of about two and two-thirds the diameter of the subsurface water pipe. 
     
     
         14 . The geothermal heat exchange system for a water supply according to  claim 8 , wherein the dispensing fixture is a washbasin. 
     
     
         15 . A geothermal heat exchange system for a water supply, comprising:
 an elevated water supply providing a pressure head;   a large diameter water supply pipe extending downward from the elevated water supply;   at least one subsurface water pipe disposed below the level of the large diameter water supply pipe, the subsurface water pipe communicating fluidly with the large diameter water supply pipe, the subsurface water pipe being buried at an intermediate depth between ground level and a level of constant temperature below ground level;   a dispensing fixture water supply pipe communicating fluidly with the at least one subsurface water pipe, the dispensing fixture water supply pipe extending upward from the subsurface water pipe to a point above the ground surface and below the elevated water supply;   a dispensing fixture disposed above the ground surface, the dispensing fixture selectively receiving water from the dispensing fixture water supply pipe; and   a wastewater drain extending from the dispensing fixture.   
     
     
         16 . The geothermal heat exchange system for a water supply according to  claim 15 , wherein the subsurface water pipe is formed of material having a high thermal conductivity. 
     
     
         17 . The geothermal heat exchange system for a water supply according to  claim 15 , wherein:
 the subsurface water pipe has a smaller diameter than the large diameter water supply pipe; and   the dispensing fixture water pipe has a smaller diameter than the large diameter water supply pipe.   
     
     
         18 . The geothermal heat exchange system for a water supply according to  claim 15 , wherein the at least one subsurface water pipe comprises a plurality of small diameter parallel pipes. 
     
     
         19 . The geothermal heat exchange system for a water supply according to  claim 15 , wherein the at least one subsurface water pipe comprises a single small diameter pipe having a sinusoidal path. 
     
     
         20 . The geothermal heat exchange system for a water supply according to  claim 15 , wherein the large diameter water supply pipe has a diameter of about two and two-thirds the diameter of the subsurface water pipe.