Thermal storage system for use in connection with a thermal conductive wall structure

Abstract

There is described a thermal storage system for transferring and storing heat in the ground, the thermal storage system comprising pumping means configured to circulate a working fluid, a heat exchanger, a supply output, a length of pipe, a return inlet and a thermally conductive ground engaging footing such that the pumping means circulates the working fluid through the length of pipe allowing heat transfer between the ground and the working fluid, the thermally conductive ground engaging footing thermally communicating with the ground.

1 . A thermal storage system for a building having a peripherally extending thermally conductive wall structure comprising:
 a footing disposed in the ground below grade;   a vertical wall supported on and extending longitudinally in the direction of the footing;   the vertical wall extending upwardly from the footing above grade to a predetermined height;   conduit means disposed in the ground a predetermined distance beneath and interiorly of said footing;   means for circulating a working fluid through said conduit means; and   means for transferring heat to or from said working fluid wherein the ground around said conduit means is respectively either heated or cooled for heat transfer between the heated or cooled ground and said footing and the wall structure supported thereon.   
     
     
         2 . The thermal storage system of  claim 1  wherein said conduit means comprise one or more loops of tubing for the flow of said working fluid therethrough. 
     
     
         3 . The thermal storage system of  claim 2  wherein each of said one or more loops of tubing has an inlet end and an outlet end in fluid communication with said means for circulation. 
     
     
         4 . The thermal storage system of  claim 3  wherein said means for circulation is a pump. 
     
     
         5 . The thermal storage system of  claim 4  wherein said means for transferring heat is a heat exchanger. 
     
     
         6 . The thermal storage system of  claim 1  wherein said predetermined distance is the radius of a zone around said conduit means that, for a given thermal input, will extend from the conduit means to a portion of said footing closest to said conduit means. 
     
     
         7 . The thermal storage system of  claim 6  wherein said predetermined distance will vary at least in part depending upon the number of days in the geographic location where the building is located where the temperature above the ground exceeds the temperature of said z one and said conduit means. 
     
     
         8 . The thermal storage system of  claim 7  wherein said building includes a floor structure circumscribed at least in part by said footing, said floor structure providing an insulating layer that acts as a thermal barrier between the interior of said building and the heated or cooled g round in said z one around the conduit means. 
     
     
         9 . The thermal storage system of  claim 8  wherein said floor structure comprises a first and second layers of insulating material. 
     
     
         10 . The thermal storage system of  claim 9  wherein said first insulating material is compacted gravel. 
     
     
         11 . The thermal storage system of  claim 10  wherein said second layer is a rigid foam insulation disposed above said compacted gravel. 
     
     
         12 . The thermal storage system of  claim 11  wherein the thickness of said compacted gravel is substantially equal to the vertical thickness of said footing. 
     
     
         13 . The thermal storage system of  claim 12  wherein said layer of compacted gravel has an upper surface and a lower surface, said upper surface including therein insulation situated between the points where said radius of said z one around said conduit means intersects said upper surface of said layer of compacted gravel. 
     
     
         14 . A thermal storage system comprising:
 a longitudinally extending ground engaging footing, said footing extending horizontally through the ground below the frost level and having an upper surface and a lower surface;   pumping means configured to circulate a working fluid;   a heat exchanger, said heat exchanger configured to transfer heat between said working fluid and the outside environment, said heat exchanger fluidly communicating with said pumping means;   at least one supply outlet, said at least one supply outlet fluidly communicating with said heat exchanger;   at least one length of pipe, said at least one length of pipe fluidly communicating with said supply output, said at least one length of pipe thermally communicating with the ground under said longitudinally extending ground engaging footing; and   at least one return inlet, said at least one return inlet fluidly communicating with said at least one pipe   wherein said pumping means circulates said working fluid through said heat exchanger to said at least one length of pipe by way of said supply outlet, said working fluid experiencing heat transfer with said at least one length of pipe, said at least one length of pipe experiencing heat transfer with the ground, said working fluid returning to said pumping means by way of said return inlet.   
     
     
         15 . The thermal storage system of  claim 14 , said thermal storage system further comprising:
 a vertical wall, said wall extending vertically above grade from said footing and longitudinally along said footing, said wall having a lower surface, an upper surface, an interior surface and an exterior surface, said lower surface abutting said footing;   a thermally conductive strip, said strip longitudinally positioned on the upper surface of said footing, said strip being located between the upper surface of said footing and the lower surface of said vertical wall;   an insulating sheath, said sheath enveloping the interior, exterior and upper surfaces of said vertical wall;   a first plurality of thermally conductive members disposed inside said vertical wall to be in thermal communication with one another, at least some of said members being in contact with said thermally conductive strip for heat transfer therebetween; and   a second plurality of thermally conductive members disposed in said footing to be in thermal communication with said thermally conductive strip for heat transfer therebetween, at least some of said second plurality of thermally conductive members extending downwardly through the lower surface of said footing into the ground a selected distance.   
     
     
         16 . The thermal storage system of  claim 15 , said thermal storage system further comprising:
 a vertical wall supported on and extending longitudinally in the direction of the footing, the vertical wall extending upwardly from the footing above grade to a predetermined height, and having upper, lower, interior, exterior and end surfaces;   a sheath of insulation for enveloping said vertical wall's upper, end, interior and exterior surfaces; and   thermal conductors disposed in said vertical wall to be in thermal communication with one another, at least some of said conductors extending outwardly from said footing into the ground, the thermal conductors facilitating heat transfer between the ground and the vertical wall.   
     
     
         17 . The thermal storage system of  claim 16 , wherein said pumping means are selected from the group consisting of: a progressive cavity pump, a positive displacement pump, a reciprocal pump and a centrifugal pump. 
     
     
         18 . The thermal storage system of  claim 17 , wherein said heat exchanger is a solar heat exchanger. 
     
     
         19 . The thermal storage system of  claim 18 , wherein said heat exchanger recovers waste heat fed from one or both of a building and heat emitting sources associated therewith. 
     
     
         20 . The thermal storage system of  claim 19 , wherein said heat exchanger is located downstream from said pumping means. 
     
     
         21 . The thermal storage system of  claim 20 , further comprising a valve located downstream of said heat exchanger. 
     
     
         22 . The thermal storage system of  claim 21 , further comprising a first lockout valve and a second lockout valve, said first lockout valve located upstream of said pumping means and said second lockout valve located downstream of said pumping means. 
     
     
         23 . The thermal storage system of  claim 15 , wherein said first plurality of thermally conductive members form one or more grids in said vertical wall. 
     
     
         24 . The thermal storage system of  claim 23 , wherein said one or more grids comprise vertically and horizontally arranged thermally conductive members, said vertically and horizontally arranged members being in thermal contact where they intersect for heat transfer therebetween. 
     
     
         25 . The thermal storage system of  claim 24 , wherein said one or more grids comprise a first grid disposed in said vertical wall proximal the interior surface thereof, said first grid extending vertically from said thermally conductive strip to a point at grade or to a selected distance above grade. 
     
     
         26 . The thermal storage system of  claim 25 , wherein said one or more grids comprise a second grid disposed in said wall structure approximately equidistant between said interior and exterior surfaces thereof, said second grid extending vertically from adjacent an upper edge of said first grid to a point just below said vertical wall's upper surface. 
     
     
         27 . The thermal storage system of  claim 26 , wherein said first and second grids are thermally linked together for heat transfer therebetween. 
     
     
         28 . The thermal storage system of  claim 15 , wherein said second plurality of thermally conductive members includes a set of dowels horizontally spaced apart in the longitudinal direction of said footing, each of said dowels extending vertically from a point a selected distance above said footing's lower surface to a point a selected distance into said vertical wall, each of said dowels contacting said thermally conductive strip for heat transfer therebetween 
     
     
         29 . The thermal storage system of  claim 15 , wherein said second plurality of thermally conductive members includes a set of dowels horizontally spaced apart in the longitudinal direction of said footing, each of said dowels extending vertically downwardly from contact with said thermally conductive strip, through said footing and into the ground by a selected distance. 
     
     
         30 . The thermal storage system of  claim 15 , wherein said vertical wall is constructed from low thermal conductivity concrete. 
     
     
         31 . The thermal storage system of  claim 15 , wherein said footing is constructed of thermally conductive concrete with a minimum thermal conductivity of 2.0 W/mK. 
     
     
         32 . The thermal storage system of  claim 15 , wherein said footing additionally comprises at least one longitudinally aligned thermally conductive member extending continuously from one end of said footing to the other. 
     
     
         33 . The thermal storage system of  claim 15 , wherein said insulating sheath is constructed of a material with an insulation value of at least R9 along the interior and exterior surfaces of said vertical wall and an insulation value of at least R25 along the upper surface of said vertical wall. 
     
     
         34 . The thermal storage system of  claim 15 , wherein said footing is located at least three feet below said frost level. 
     
     
         35 . The thermal storage system of  claim 32 , wherein said first and second plurality of thermally conductive members and said longitudinally aligned thermally conductive member are metallic rods. 
     
     
         36 . The thermal storage system of  claim 35 , wherein said metallic rods reinforce said footing and said vertical wall. 
     
     
         37 . The thermal storage system of  claim 16 , wherein said thermal conductors include a first plurality of thermally conductive members disposed inside said vertical wall in thermal communication with one another. 
     
     
         38 . The thermal storage system of  claim 37  wherein said thermal conductors include a second plurality of thermally conductive members disposed in said footing, at least some of second plurality of thermally conductive members extending outwardly from said footing into the ground a selected distance, said first and second plurality of thermally conductive members being in thermal communication for heat transfer therebetween. 
     
     
         39 . The thermal storage system of  claim 38  wherein said thermal conductors include a thermally conductive strip disposed on said footing and extending longitudinally therealong, said thermally conductive strip being disposed between the footing and the vertical wall's lower surface. 
     
     
         40 . The thermal storage system of  claim 39  wherein at least some of said first and second plurality of thermally conductive members contact said thermally conductive strip for heat transfer therebetween and to thermally connect said first and second pluralities of thermally conductive members. 
     
     
         41 . The thermal storage system of  claim 40 , wherein said first plurality of thermally conductive members form one or more grids in said vertical wall. 
     
     
         42 . The thermal storage system of  claim 41  wherein said one or more grids comprise vertically and horizontally arranged thermally conductive members, said vertically and horizontally arranged members being in thermal contact where they intersect for heat transfer therebetween. 
     
     
         43 . The thermal storage system of  claim 42 , wherein said one or more grids comprise a first grid disposed in said vertical wall proximal the interior surface thereof, said first grid extending vertically from said thermally conductive strip to a point at grade or a selected distance above grade. 
     
     
         44 . The thermal storage system of  claim 43 , wherein said one or more grids comprise a second grid disposed in said wall structure approximately equidistant between said interior and exterior surfaces thereof, said second grid extending vertically from adjacent an upper edge of said first grid to a point just below said vertical wall's upper surface. 
     
     
         45 . The thermal storage system of  claim 44 , wherein said first and second grids are thermally linked together for heat transfer therebetween. 
     
     
         46 . The thermal storage system of  claim 45 , wherein said second plurality of thermally conductive members includes a set of dowels horizontally spaced apart in the longitudinal direction of said footing, each of said dowels extending vertically from a point a selected distance above said footing's lower surface to a point a selected distance into said vertical wall, each of said dowels thermally contacting said thermally conductive strip for heat transfer therebetween. 
     
     
         47 . The thermal storage system of  claim 46 , wherein said second plurality of thermally conductive members includes a set of dowels horizontally spaced apart in the longitudinal direction of said footing, each of said dowels extending vertically downwardly from thermal contact with said thermally conductive strip, through said footing and into the ground a selected distance. 
     
     
         48 . The thermal storage system of  claim 16 , wherein said footing additionally comprises at least one longitudinally aligned thermally conductive member extending continuously from one end of said footing to the other. 
     
     
         49 . The thermal storage system of  claim 48 , wherein said first and second plurality of thermally conductive members and said longitudinally aligned thermally conductive member are metal rods. 
     
     
         50 . A method of storing heat in the ground beneath a building, comprising the steps of:
 burying at least one length of pipe in the ground below the frost level, said at least one length of pipe configured to receive a working fluid from a heat exchanger, the at least one pipe thermally communicating with the ground below the frost level;   forming a longitudinally extending footing in the ground above said at least one length of pipe;   supporting a vertical wall on the footing, the vertical wall extending upwardly from the footing to a selected height above grade;   sheathing the vertical wall in insulation;   lacing the interior of the vertical wall and the footing with thermally communicating heat conducting members, at least some of the heat conducting members extending outwardly from the footing into the ground a selected distance to facilitate heat transfer between the ground and the vertical wall.