U.S. patent application number 11/559889 was filed with the patent office on 2007-12-27 for geothermal exchange system using a thermally superconducting medium with a refrigerant loop.
Invention is credited to John Graham, Lynn Mueller, David Todd.
Application Number | 20070295477 11/559889 |
Document ID | / |
Family ID | 38022938 |
Filed Date | 2007-12-27 |
United States Patent
Application |
20070295477 |
Kind Code |
A1 |
Mueller; Lynn ; et
al. |
December 27, 2007 |
Geothermal Exchange System Using A Thermally Superconducting Medium
With A Refrigerant Loop
Abstract
A geothermal exchange system is couplable to a ground coil
formed from a thermal superconductor material, and transfers heat
using a refrigerant loop. The device includes a compressor, a
reversible refrigerant loop with two heat exchangers, one of which
couplable to a thermal superconductor ground loop. The device uses
a high thermal transfer superconductor to efficiently move heat to
and from the earth source for the purpose of heating and cooling.
The device operates in cooling or heating modes by controlling the
thermal switches and activating the heat intensification circuit in
response to the difference between a set point and a measured
temperature. Alternatively, the system can be configured for
heating only or cooling only modes, by operating the refrigerant
loop in one direction.
Inventors: |
Mueller; Lynn; (Richmond,
CA) ; Graham; John; (Vancouver, CA) ; Todd;
David; (Vancouver, CA) |
Correspondence
Address: |
MCANDREWS HELD & MALLOY, LTD
500 WEST MADISON STREET
SUITE 3400
CHICAGO
IL
60661
US
|
Family ID: |
38022938 |
Appl. No.: |
11/559889 |
Filed: |
November 14, 2006 |
Current U.S.
Class: |
165/45 ; 432/62;
62/260 |
Current CPC
Class: |
F25B 30/06 20130101;
Y02E 10/10 20130101; F25B 2313/002 20130101; F24T 10/40 20180501;
F28D 15/0266 20130101; F28F 13/18 20130101; F28F 21/089 20130101;
F25B 13/00 20130101 |
Class at
Publication: |
165/045 ;
432/062; 062/260 |
International
Class: |
F24J 3/08 20060101
F24J003/08; F25B 30/00 20060101 F25B030/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 14, 2005 |
CA |
2,526,356 |
Claims
1. A geothermal exchange system employing a refrigerant loop with
high heat transfer superconductor couplable to earth source, the
system comprising: (a) a compressor; (b) a first heat exchanger and
a second heat exchanger, each of said heat exchangers adapted to
function interchangeably as an evaporator and a condenser, wherein
said first heat exchanger is operable as an evaporator and said
second heat exchanger is operable as a condenser when said system
is operating in a cooling mode, and wherein said first heat
exchanger is operable as a condenser and said second heat exchanger
is operable as an evaporator when said system is operating in a
heating mode; (c) at least one first conduit in communication with
said compressor and each of said heat exchangers and adapted for
carrying refrigerant through said system to each of said heat
exchangers, said at least one conduit including a return conduit
for carrying refrigerant gas back to said compressor; (d) a
reversing valve in communication with said at least one conduit and
configured to reverse the flow of refrigerant from said compressor
to said heat exchangers depending upon whether said system is
operating in said cooling mode or said heating mode; (e) at least
one of: (1) an above-ground thermal superconductor segment
thermally coupled to said second heat exchanger; (2) a thermal
interconnect thermally coupled to said second heat exchanger, and
thermally couplable to a thermal superconductor segment such that
heat transfer losses are less than 20%; whereby, when said system
is operating in heating mode, said valve is activated to direct
refrigerant pumped from said compressor through said at least one
conduit to said first heat exchanger where said refrigerant gas is
condensed into liquid, through said return conduit to said second
heat exchanger where said liquid is vaporized into gas and heat is
efficiently transferred from earth source through at least one of
said thermal superconductor and said thermal interconnect, and back
to said compressor via said return conduit; and whereby, when said
system is operating in cooling mode, said valve is activated to
direct refrigerant pumped from said compressor through said at
least one conduit to said second heat exchanger where said
refrigerant gas is condensed into liquid and heat is efficiently
transferable to earth source through at least one of said thermal
superconductor and said thermal interconnect, through said return
conduit to said first heat exchanger wherein said liquid is
vaporized into gas, and back to said compressor via said return
conduit.
2. The geothermal exchange system of claim 1, further comprising at
least one exterior thermally superconducting ground coil formed
from a high heat transfer superconducting material, extending below
a surface of earth allowing passive thermal conduction to the earth
source and couplable to at least one of said thermal superconductor
and said thermal interconnect.
3. The geothermal exchange system of claim 1, further comprising a
thermostat controller associated with said first heat exchanger and
in communication with said reversing valve and said compressor, for
controlling the valve and resultant heating or cooling mode in
response to the difference between a desired temperature set point
and a measured temperature set point received by the
thermostat.
4. The geothermal exchange system of claim 1, wherein said thermal
superconductor material is an inorganic high heat transfer
medium.
5. The geothermal exchange system of claim 4, wherein said high
heat transfer medium is applied in a sealed heat transfer pipe.
6. The geothermal exchange system of claim 5, wherein said heat
transfer pipe containing said high heat transfer medium is
insulated above ground along a heat transfer segment extending up
to said thermal coupling to said second heat exchanger, said heat
transfer pipe having thermal conductivity greater than 100 times
the thermal conductivity of silver, and substantially negligible
heat loss along said heat transfer segment.
7. The geothermal exchange system of claim 3, further comprising a
blower positioned proximal to said first heat exchanger, and
wherein said thermostat controller is connected to said blower to
control operation in response to the difference between said set
point and said measured temperature for the purpose of heating and
cooling inside air.
8. The geothermal exchange system of claim 3, further comprising an
auxiliary heat exchanger coupled to said first heat exchanger, for
the purpose of exchanging heat from or to said geothermal exchange
system.
9. The geothermal exchange system of claim 7, wherein said first
heat exchanger is coupled to a sealable insulated enclosure, for
the purpose of refrigerating the interior of said enclosure.
10. The geothermal exchange system of claim 3, further comprising a
secondary interior heat exchanger coupled to said first heat
exchanger, for the purpose of exchanging heat in one of said
heating and cooling modes.
11. The geothermal exchange system of claim 10, wherein said
secondary heat exchanger uses liquid for heat transfer.
12. The geothermal exchange system of claim 11, wherein said liquid
is water used for floor heating of said interior space.
13. The geothermal exchange system of claim 11, wherein said liquid
is water used for domestic purposes.
14. The geothermal exchange system of claim 11, wherein said liquid
is greywater used for heat recovery.
15. The geothermal exchange system of claim 7, further comprising:
a first enclosure housing said compressor, said second heat
exchanger, said controller and said reversing valve; and a second
enclosure housing said first heat exchanger and said blower
positioned proximal to said segment, and having at least one vent
formed therein; wherein said first enclosure has openings formed
therein to couple at least one of said thermal superconductor and
said thermal interconnect, conduits and control lines, and said
first enclosure and said second enclosure are connected by said
conduit and control wires from said blower.
16. The geothermal exchange system of claim 7, further comprising:
a first enclosure housing said compressor, controller means and
reversing valve, a second enclosure housing said first heat
exchanger and said blower positioned proximal to said segment, and
having at least one vent formed therein; and a ground loop
enclosure housing said second heat exchanger; wherein said first
enclosure has openings formed therein to couple to at least one of
said thermal superconductor and said thermal interconnect, conduits
and control lines, and said first enclosure and said second
enclosure are connected by said conduit and control wires from said
blower, and said ground loop enclosure housing is connected to said
first enclosure housing by said conduit.
17. The geothermal exchange system of claim 3, further comprising
an enclosure housing said compressor, said thermostat, said first
and second heat exchangers, said blower, and having at least one
vent formed therein, wherein said enclosure has at least one
opening formed therein for at least one of said thermal
superconductor and said thermal interconnect to couple to said
second heat exchanger, power source connections, and a water drain
line.
18. The geothermal exchange system of claim 3, further comprising:
a first enclosure housing said compressor, said thermostat, said
first heat exchanger, said blower, and having at least one vent
formed therein; a second enclosure housing said second heat
exchanger; wherein said second enclosure has at least one opening
formed therein for at least one of said thermal superconductor and
said thermal interconnect to couple to said second heat
exchanger.
19. The geothermal exchange system of claim 7, further comprising a
thermal mass contacting both above ground superconductor and said
second heat exchanger, to indirectly transfer heat between
both.
20. The geothermal exchange system of claim 2, wherein at least a
portion of said thermal superconductors are formed in discrete
segments joined by substantially short thermally conducting
joiners.
21. The geothermal exchange system of claim 3, further comprising a
receiver connected to said thermostat controller and a remote
control for communicating information with said receiver such that
thermostat set points and operations are wirelessly
controllable.
22. A heating device using an efficient geothermal system with high
heat transfer superconductor couplable to earth source, the device
comprising: (a) a compressor; (b) a first heat exchanger and a
second heat exchanger, wherein said first heat exchanger is
operable as an evaporator and said second heat exchanger is
operable as a condenser in a cooling mode; (c) at least one first
conduit in communication with said compressor and first heat
exchanger and adapted for carrying refrigerant through said system
to each of said heat exchangers, said at least one conduit
including a return conduit for carrying refrigerant gas back to
said compressor from said second heat exchanger; (d) at least one
of: (1) an above ground thermal superconductor segment thermally
coupled to said second heat exchanger; and (2) a thermal
interconnect thermally coupled to said second heat exchanger, and
thermally couplable to a thermal superconductor segment such that
heat transfer losses are less than 20%; whereby refrigerant is
pumped from said compressor through said at least one conduit to
said second heat exchanger where said refrigerant gas is condensed
into liquid and heat is efficiently transferred to earth source
through at least one of said thermal superconductor and said
thermal interconnect, said refrigerant transfers through said
return conduit to said first heat exchanger wherein said liquid is
vaporized into gas, and back to said compressor via said return
conduit.
23. The heating device of claim 22, further comprising at least one
exterior thermally superconducting ground coil formed from a high
heat transfer superconducting material, extending below a surface
of earth allowing passive thermal conduction to the earth source
and couplable to at least one of said thermal superconductor and
said thermal interconnect.
24. The heating device of claim 22, further comprising a thermostat
controller associated with said first heat exchanger and in
communication with said compressor, for controlling the operation
of the compressor in response to the difference between a desired
temperature set point and a measured temperature set point received
by the thermostat.
25. The heating device of claim 22, wherein said thermal
superconductor material is an inorganic high heat transfer
medium.
26. The heating device of claim 25, wherein said high heat transfer
medium is applied in a sealed heat transfer pipe.
27. The heating device of claim 26, wherein said heat transfer pipe
containing said high heat transfer medium is insulated above ground
along a heat transfer segment extending up to said thermal coupling
to said second heat exchanger, said heat transfer pipe having
thermal conductivity greater than 100 times the thermal
conductivity of silver, and substantially negligible heat loss
along said heat transfer segment.
28. The heating device of claim 24, further comprising a blower
positioned proximal to said first heat exchanger, and wherein said
thermostat controller is connected to said blower to control
operation in response to the difference between said set point and
said measured temperature for the purpose of cooling inside
air.
29. The heating device of claim 22, further comprising an auxiliary
heat exchanger coupled to said first heat exchanger, for the
purpose of exchanging auxiliary heat.
30. The heating device of claim 29, wherein said secondary heat
exchanger uses liquid for heat transfer.
31. The heating device of claim 30, wherein said liquid is water
used for floor heating of said interior space.
32. The heating device of claim 30, wherein said liquid is water
used for domestic purposes.
33. The heating device of claim 30, wherein said liquid is
greywater used for heat recovery.
34. The heating device of claim 28 further comprising an enclosure
housing said compressor, said thermostat, said first and second
heat exchangers, said blower, and having at least one vent formed
therein, wherein said enclosure has at least one opening formed
therein for at least one of said thermal superconductor and said
thermal interconnect to couple to said second heat exchanger, power
source connections, and a water drain line.
35. The heating device of claim 28, further comprising, a first
enclosure housing said compressor, said second heat exchanger and
said controller; and a second enclosure housing said first heat
exchanger and said blower positioned proximal to said segment, and
having at least one vent formed therein; wherein said first
enclosure has openings formed therein to couple at least one of
said thermal superconductor and said thermal interconnect, conduits
and control lines, and said first enclosure and said second
enclosure are couplable by at least one of said thermal
superconductor and said thermal interconnect and control wires from
said blower.
36. The heating device of claim 22, further comprising an a thermal
mass contacting both above ground superconductor and said second
heat exchanger, to indirectly transfer heat between both.
37. The heating device of claim 23, wherein at least a portion of
said thermal superconductors are formed in discrete segments joined
by substantially short thermally conducting joiners.
38. The heating device of claim 24, further comprising a receiver
connected to said thermostat controller and a remote control for
communicating information with said receiver such that thermostat
set points and operations are wirelessly controllable.
39. A cooling device employing an efficient geothermal system with
a high heat transfer superconductor couplable to earth source, the
device comprising: (a) a compressor; (b) a first heat exchanger and
a second heat exchanger, wherein said first heat exchanger is
operable as an evaporator and said second heat exchanger is
operable as a condenser in a cooling mode; (c) at least one first
conduit in communication with said compressor and first heat
exchanger and adapted for carrying refrigerant through said system
to each of said heat exchangers, said at least one conduit
including a return conduit for carrying refrigerant gas back to
said compressor from said second heat exchanger; (d) at least one
of: (1) an above ground thermal superconductor segment thermally
coupled to said second heat exchanger; and (2) a thermal
interconnect thermally coupled to said second heat exchanger, and
thermally couplable to thermal superconductor segment such that
heat transfer losses are less than 20%; whereby refrigerant is
pumped from said compressor through said at least one conduit to
said second heat exchanger where said refrigerant gas is condensed
into liquid and heat is efficiently transferred to earth source
through at least one of said thermal superconductor and said
thermal interconnect, said refrigerant transfers through said
return conduit to said first heat exchanger wherein said liquid is
vaporized into gas, and back to said compressor via said return
conduit.
40. The cooling device of claim 39, further comprising at least one
exterior thermally superconducting ground coil formed from a high
heat transfer superconducting material, extending below a surface
of earth allowing passive thermal conduction to the earth source
and couplable to at least one of said thermal superconductor and
said thermal interconnect.
41. The cooling device of claim 39, further comprising a thermostat
controller associated with said first heat exchanger and in
communication with said compressor, for controlling the operation
of the compressor in response to the difference between a desired
temperature set point and a measured temperature set point received
by the thermostat.
42. The cooling device of claim 39, wherein said thermal
superconductor material is an inorganic high heat transfer
medium.
43. The cooling device of claim 42, wherein said high heat transfer
medium is applied in a sealed heat transfer pipe.
44. The cooling device of claim 43, wherein said heat transfer pipe
containing said high heat transfer medium is insulated above ground
along a heat transfer segment extending up to said thermal coupling
to said second heat exchanger, said heat transfer pipe having
thermal conductivity greater than 100 times the thermal
conductivity of silver, and substantially negligible heat loss
along said heat transfer segment.
45. The cooling device of claim 41, further comprising a blower
positioned proximal to said first heat exchanger, and wherein said
thermostat controller is connected to said blower to control
operation in response to the difference between said set point and
said measured temperature for the purpose of cooling inside
air.
46. The cooling device of claim 39, wherein said first heat
exchanger is coupled to a sealable insulated enclosure, for the
purpose of refrigerating the interior of said enclosure.
47. The cooling device of claim 41, further comprising an enclosure
housing said compressor, said thermostat, said first and second
heat exchangers, said blower, and having at least one vent formed
therein, wherein said enclosure has at least one opening formed
therein for at least one of said thermal superconductor and said
thermal interconnect to couple to said second heat exchanger, power
source connections, and a water drain line.
48. The cooling device of claim 22, further comprising: a first
housing said compressor, said second heat exchanger and said
controller; and a second enclosure housing said first heat
exchanger and said blower positioned proximal to said segment, and
having at least one vent formed therein, wherein said first
enclosure has openings to couple at least one of said thermal
superconductor and said thermal interconnect, conduits and control
lines, and said first enclosure and said second enclosure are
couplable by at least one of said thermal superconductor and said
thermal interconnect and control wires from said blower.
49. The cooling device of claim 40, further comprising an a thermal
mass contacting both above ground superconductor and said second
heat exchanger, to indirectly transfer heat between both.
50. The cooling device of claim 40, wherein at least a portion of
said thermal superconductors are formed in discrete segments joined
by substantially short thermally conducting joiners.
51. The cooling device of claim 41, further comprising a receiver
connected to said thermostat controller and a remote control for
communicating information with said receiver such that thermostat
set points and operations are wirelessly controllable.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to geothermal
cooling systems, and more particularly to a geothermal cooling
device coupled with a superconducting heat transfer element for use
as an air conditioner.
BACKGROUND OF THE INVENTION
[0002] Ground source heat pump systems, also known geothermal or
geoexchange systems, have been used for heating and cooling
buildings for more than half a century. In 1993, the Environmental
Protection Agency evaluated all available heating and cooling
technologies and concluded that ground source heat pump systems
were the most energy efficient systems available in the consumer
marketplace.
[0003] Conventional ground source heat pump systems operate on a
simple principle. In the heating mode they collect heat energy from
the ground and transfer it to a heat pump, which concentrates the
heat and transfers it to a building's heat distribution system
which in turn heats the building. In the cooling mode, heat from
the building is collected by the cooling system and transferred to
the heat pump, which concentrates the energy and transfers it to a
ground source loop, which transfers the heat to the ground. In both
modes, only a small amount of the heat comes from the electricity
that runs the compressor; most of the heating and cooling energy
comes from the ground. This allows ground source heat pump systems
to achieve more than 100% efficiency: every unit of electrical
energy consumed by the heat pump produces more useable heat than an
electrical resistance heater can produce with the same unit of
electricity.
[0004] Even though ground source heat pump systems achieve
efficiencies of up to 350% compared to less than 100% for many
conventional systems, they have been slow to penetrate the consumer
marketplace because of high capital costs, high installation costs,
difficult installation procedures and low energy cost savings due
to historically low energy prices.
[0005] These high capital and installation costs have largely been
due to fundamental inefficiencies in the ground loop subsystem. In
a typical installation, the ground loop consists of hundreds or
thousands of feet of looped plastic piping buried in deep trenches
or deep holes drilled into the ground. An antifreeze solution is
pumped through this loop to absorb heat energy from the ground (in
the heating mode) or transfer heat energy to the ground (in the
cooling mode.) Few installations have sufficient available land for
trenching so loops are most commonly installed in deep holes and
this makes them relatively expensive for several reasons.
[0006] First, each loop consists of a supply and return line, which
should fit down the same hole. With an outer diameter of an inch or
more for each pipe and a tendency for these pipes to bow away from
each other due to the plastic material's memory of being coiled for
shipment, the hole should typically have a diameter of 4 to 6
inches to allow the loop to be installed. Holes of this size are
relatively expensive to drill and require heavy equipment that
disrupts landscaping, making it expensive to retrofit existing
homes. Holes of this size also leave large voids around the loop
that should be filled with materials such as bentonite clay in
order for heat to transfer from the ground to the loop, which adds
significantly to the cost of installation.
[0007] Second, having both supply and return lines in the same hole
results in thermal "short circuiting" which reduces the efficiency
of the loop. In the heating mode, for example, cool fluid from the
heat pump absorbs heat from the ground as it goes down the supply
line in the hole, cooling the ground around the pipe. When the
warmed fluid comes back up the hole in the return line, it passes
through the ground that was just cooled, losing some of the heat it
has just picked up. This lowers the efficiency of the loop so the
loop should be made longer to compensate, adding to the cost of
drilling and piping.
[0008] Third, for the ground loop to function, the antifreeze
solution should be pumped through hundreds or thousands of feet of
small diameter piping. This consumes a significant amount of
electric energy, lowering the overall efficiency of the system.
[0009] In recent years, a new ground source heat pump technology
has evolved to overcome some of the inefficiencies of conventional
systems. This technology, called "direct geoexchange," replaces the
conventional plastic ground loop with a small-diameter copper loop.
Instead of an antifreeze solution, direct geoexchange systems pump
a refrigerant through the loop to pick up heat from the ground or
give off heat to the ground in the same way that conventional
ground loops function.
[0010] Direct geoexchange has some significant advantages over
conventional systems. First, the direct geoexchange loop runs
directly to and from the heat pump's compressor, eliminating the
heat exchanger that is required by conventional systems to transfer
heat from the loop to the heat pump. Second, the small diameter of
the direct exchange loop makes it possible for loops to be
installed in smaller diameter holes in the ground; this reduces the
cost of drilling and backfilling the holes and reduces the size of
the drill rig required to drill the holes, decreasing damage to
landscaping in retrofit applications. Third, the copper pipes used
in direct geoexchange transfer heat more efficiently to and from
the ground so the total length of loop required is typically less
than conventional systems. Because of these improvements, direct
geoexchange systems can be cheaper than conventional ground source
systems and more energy efficient.
[0011] In spite of these inherent advantages, direct geoexchange
also has some significant disadvantages. First, both supply and
return pipes run in the same hole, so the thermal short circuit
problems of conventional systems remain. Second, the loop system
pumps much more refrigerant through many more feet of piping past
many more connections than conventional systems, so the potential
for refrigerant leaks is increased. Third, direct geoexchange
requires large volumes of refrigerant to flow through the loop,
behaving differently in the heating and cooling modes, and
requiring additional refrigerant reservoirs and flow control
systems to compensate. Because of these inefficiencies, direct
geoexchange is only able to achieve a modest improvement in total
energy efficiency over conventional ground source heat pump
systems.
[0012] Direct geoexchange and conventional ground source heat pump
systems have additional limitations. Both require a significant
amount of electrical power to pump fluids through hundreds or
thousands of feet of piping. This not only limits overall system
efficiency but also limits the environments in which it can be
installed. This kind of power is not often available or reliable in
the world's developing countries, so existing ground source heat
pump systems have limited potential to penetrate broad world
markets. In addition, since both systems are designed to heat and
cool whole buildings, neither can efficiently be installed on the
incremental room-by-room basis on which most of the world adopts
heating and air conditioning.
[0013] In summary, conventional geoexchange systems and direct
expansion geoexchange systems have significant limitations in
energy efficiency, installation cost and installation
flexibility.
[0014] There is a need, therefore, for a geothermal exchange system
that operates in combination with a refrigerant heat
intensification loop, utilizes less power than conventional
refrigerant or coolant based geoexchange systems, results in
lightweight heat exchangers that can be configured in a wide range
of interior locations, has an extended lifetime due to fewer parts,
has reduced ground loop installation costs and provides enhanced
cooling and heating efficiency compared to power used.
SUMMARY OF THE INVENTION
[0015] In one embodiment, a geothermal exchange system uses a
refrigerant loop with high heat transfer superconductor couplable
to an earth source. The system includes a compressor, a first heat
exchanger and a second heat exchanger, each of the heat exchangers
adapted to function interchangeably as an evaporator and a
condenser, such that the first heat exchanger is operable as an
evaporator and the second heat exchanger is operable as a condenser
when the system is operating in cooling mode, and such that the
first heat exchanger is operable as a condenser and the second heat
exchanger is operable as an evaporator when the system is operating
in heating mode, at least one first conduit in communication with
the compressor and each of the heat exchangers and adapted for
carrying refrigerant through the system to each of the heat
exchangers, the at least one conduit including a return conduit for
carrying refrigerant gas back to the compressor, a reversing valve
in communication with said at least one conduit and configured to
reverse the flow of refrigerant from the compressor to the heat
exchangers depending upon whether the system is operating in the
cooling mode or the heating mode; and at least one of either an
above-ground thermal superconductor segment thermally coupled to
said second heat exchanger or a thermal interconnect thermally
coupled to said second heat exchanger, and thermally couplable to a
thermal superconductor segment such that heat transfer losses are
less than 20%.
[0016] When the system is operating in heating mode, the valve is
activated to direct refrigerant pumped from the compressor through
the at least one conduit to the first heat exchanger where the
refrigerant gas is condensed into liquid, through the return
conduit to the second heat exchanger where the liquid is vaporized
into gas and heat is efficiently transferred from earth source
through the thermal superconductor, and back to the compressor via
the return conduit; and such that when the system is operating in
cooling mode, the valve is activated to direct refrigerant pumped
from the compressor through the at least one conduit to the second
heat exchanger where the refrigerant gas is condensed into liquid
and heat is efficiently transferred to earth source through the
thermal superconductor, through the return conduit to the first
heat exchanger wherein the liquid is vaporized into gas, and back
to the compressor via the return conduit.
[0017] In another embodiment, a cooling device using an efficient
geothermal system with a high heat transfer superconductor
couplable to an earth source. The cooling device includes a
compressor, a first heat exchanger and a second heat exchanger,
such that the first heat exchanger is operable as an evaporator and
the second heat exchanger is operable as a condenser in a cooling
mode, at least one first conduit in communication with the
compressor and first heat exchanger and adapted for carrying
refrigerant through the system to each of the heat exchangers, the
at least one conduit including a return conduit for carrying
refrigerant gas back to the compressor from the second heat
exchanger, and at least one of either an above-ground thermal
superconductor segment thermally coupled to said second heat
exchanger or a thermal interconnect thermally coupled to said
second heat exchanger, and thermally couplable to a thermal
superconductor segment such that heat transfer losses are less than
20%, and such that refrigerant is pumped from the compressor
through the at least one conduit to the second heat exchanger where
the refrigerant gas is condensed into liquid and heat is
efficiently transferred to earth source through the thermal
superconductor, the refrigerant transfers through the return
conduit to the first heat exchanger wherein the liquid is vaporized
into gas, and back to the compressor via the return conduit.
[0018] In another embodiment, a heating device using an efficient
geothermal system with high heat transfer superconductor couplable
to an earth source. The heating device includes, a compressor, a
first heat exchanger and a second heat exchanger, such that the
first heat exchanger is operable as an evaporator and the second
heat exchanger is operable as a condenser in a cooling mode at
least one first conduit in communication with the compressor and
first heat exchanger and adapted for carrying refrigerant through
the system to each of the heat exchangers, the at least one conduit
including a return conduit for carrying refrigerant gas back to the
compressor from the second heat exchanger, and at least one of
either an above-ground thermal superconductor segment thermally
coupled to said second heat exchanger or a thermal interconnect
thermally coupled to said second heat exchanger, and thermally
couplable to a thermal superconductor segment such that heat
transfer losses are less than 20%, such that refrigerant is pumped
from the compressor through the at least one conduit to the second
heat exchanger where the refrigerant gas is condensed into liquid
and heat is efficiently transferred to earth source through the
thermal superconductor, the refrigerant transfers through the
return conduit to the first heat exchanger wherein the liquid is
vaporized into gas, and back to the compressor via the return
conduit.
BRIEF DESCRIPTION OF THE DRAWING(S)
[0019] FIG. 1 is a schematic diagram of an efficient geothermal
exchange system with thermal superconductor transfer from a ground
source to a reversing refrigerant based heat pump.
[0020] FIG. 2 is a schematic diagram schematic of an efficient
geothermal exchange system with a plurality of ground source
components.
[0021] FIG. 3 is a schematic diagram of an efficient geothermal
exchange system with thermal superconductor transfer from a ground
source to a reversing refrigerant based heat pump configured for
air heat exchange.
[0022] FIG. 4 is a schematic diagram schematic of an efficient
geothermal exchange system with thermal superconductor transfer
from a ground source to a reversing refrigerant based heat pump
configured for direct thermal exchange to a circulating fluid in a
tank.
[0023] FIG. 5 is a schematic diagram schematic of an efficient
geothermal exchange system with thermal superconductor transfer
from a ground source to a reversing refrigerant based heat pump
configured for indirect thermal exchange to a circulating fluid by
way of an intermediating fluid in a tank.
[0024] FIG. 6 is a schematic diagram of a geothermal cooling device
with a power connector for manually powering the blower for
additional air heat transfer.
[0025] FIG. 7 is a schematic diagram of an efficient geothermal
exchange system showing separate housings for groups of system
components. FIG. 7a shows air exchange components housed separately
from other components. FIG. 7b illustrates an enclosure for air
exchange components.
[0026] FIG. 8 is a schematic diagram of an efficient geothermal
exchange system showing separate housings for groups of system
components, with air exchange components, ground source heat
exchanger components and remaining above-ground components housed
in separate enclosures.
[0027] FIG. 9 is a schematic diagram of an efficient geothermal
exchange system with thermal superconductor transfer from a ground
source to a reversing refrigerant based heat pump.
[0028] FIG. 10 is a schematic diagram of an efficient geothermal
exchange system with thermal superconductor transfer from a ground
source to a reversing refrigerant based heat pump configured for
air heat exchange.
[0029] FIG. 11 is a schematic diagram of an efficient geothermal
exchange system with thermal superconductor transfer from a ground
source to a reversing refrigerant based heat pump configured for
direct thermal exchange to a circulating fluid in a tank.
[0030] FIG. 12 is a schematic diagram of an efficient geothermal
exchange system with thermal superconductor transfer from a ground
source to a reversing refrigerant based heat pump configured for
indirect thermal exchange to a circulating fluid by way of an
intermediating fluid in a tank.
[0031] FIG. 13 is a schematic diagram of an efficient geothermal
exchange system with thermal superconductor transfer from a ground
source to a reversing refrigerant based heat pump configured for
direct thermal exchange to a fluid loop.
[0032] FIG. 14 is a schematic diagram of an efficient geothermal
exchange system showing separate housings for groups of system
components. FIG. 14a shows air exchange components housed
separately from other components. FIG. 14b illustrates an enclosure
for air exchange components.
[0033] FIG. 15 is a schematic diagram of an efficient geothermal
exchange system showing separate housings for groups of system
components, with air exchange components, ground source heat
exchanger components and remaining above-ground components housed
in separate enclosures.
[0034] FIG. 16 is a schematic diagram of an efficient geothermal
exchange system with thermal superconductor transfer from a ground
source to a reversing refrigerant based heat pump.
[0035] FIG. 17 is a schematic diagram of an efficient geothermal
exchange system with thermal superconductor transfer from a ground
source to a reversing refrigerant based heat pump configured for
air heat exchange.
[0036] FIG. 18 is a schematic diagram of an efficient geothermal
exchange system showing separate housings for groups of system
components. FIG. 18a shows air exchange components housed
separately from other components. FIG. 18b illustrates an enclosure
for air exchange components.
[0037] FIG. 19 is a schematic diagram of an efficient geothermal
exchange system showing separate housings for groups of system
components, with air exchange components, ground source heat
exchanger components and remaining above-ground components housed
in separate enclosures.
[0038] FIG. 20a is a schematic diagram of an efficient geothermal
exchange system couplable to a superconducting geoexchange ground
loop. FIG. 20b shows the ground source heat exchange component of
the system of FIG. 20a configured to receive the end of a
superconducting ground source element, with direct metal-to-metal
thermal conduction. FIG. 20c shows the ground source heat exchange
component configured for indirect coupling with a superconducting
ground source element through an intermediating thermal paste.
[0039] FIG. 21 a shows a heat exchanger with a refrigerant coil
wound around a metal sleeve that is configured to receive the end
of a superconducting ground source component. FIG. 21b shows a heat
exchanger with a refrigerant vessel surrounding a metal sleeve,
which is configured to receive the end of a superconducting ground
source component.
[0040] FIG. 22 is a schematic diagram of an efficient geothermal
exchange cooling system with a ground source heat exchange
component configured to receive a superconducting ground loop
component.
[0041] FIG. 23 is a schematic diagram of an efficient geothermal
exchange cooling system with a ground source heat exchange
component configured to receive a superconducting ground loop
component.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT(S)
[0042] With reference to the drawings, new and improved heating and
cooling devices and geothermal exchange systems embodying the
principles and concepts of the present device will be described. In
particular, the devices and systems are applicable for climate
control within structures as well as more generally to
bi-directional heat transfer to and from earth sources. The
embodiments shown in the attached figures satisfy the need for a
geothermal exchange system with improved thermal efficiency, lower
installation cost and greater installation flexibility.
[0043] Recent advances in thermal superconducting materials can now
be considered for use in novel energy transfer applications. For
example, U.S. Pat. No. 6,132,823 and continuations thereof,
discloses an example of a heat transfer medium with extremely high
thermal conductivity, and is included herein by reference.
Specifically the following disclosure indicates the orders of
magnitude improvement in thermal conduction; "Experimentation has
shown that a steel conduit 4 with medium 6 properly disposed
therein has a thermal conductivity that is generally 20,000 times
higher than the thermal conductivity of silver, and can reach under
laboratory conditions a thermal conductivity that is 30,000 times
higher that the thermal conductivity of silver." Such a medium is
thermally superconducting. In this disclosure, the term
superconductor shall interchangeably mean thermal superconductor or
thermal superconductor heat pipe. The available product sold by Qu
Energy International Corporation is an inorganic heat transfer
medium provided in a vacuum sealed heat conducting tube.
[0044] Alternate thermal superconductors may be equivalently
substituted, such as thermally superconducting heat pipes. Heat
pipes typically include a sealed container (pipe), working fluid
and a wicking or capillary structure inside the container. Heat is
transported by an evaporation-condensation cycle when a thermal
differential is present between opposing ends. Working fluids can
be selected with high surface tension to generate a high capillary
driving force such that the condensate can migrate back to the
evaporator portion, even against gravity. Some working fluids
useful for the geothermal operating temperature range include
ammonia, acetone, methanol and ethanol. Inside the tube, the liquid
enters and wets the internal surfaces of the capillary structure.
Applying heat at one segment of the pipe, causes the liquid at that
point to vaporize picking up latent heat of vaporization. The gas
moves to a colder location where it condenses, giving up latent
heat of vaporization. The heat transfer capacity of a heat pipe is
proportional to the axial power rating, the energy moving axially
along the pipe. For maximum energy transfer the heat pipe diameter
should be increased and the length shortened, making it operable
but less preferred than a non-liquid superconductor such as the Qu
product. In particular with respect to the ground loop, scaled-up
heat pipe designs have been disclosed for geothermal heating
applications, such as in PCT Publication No. WO 86/00124
("Improvements in earth heat recovery systems"). These designs
partially overcome the length to diameter ratio problem but
preferably require a recirculation pump for the fluid. A two-way
heat pipe design for ventilation heat-exchanger is disclosed in
U.S. Pat. No. 4,896,716, and could be used for non-ground loop
transfer as a two-way thermal superconductor.
[0045] FIG. 1 illustrates an embodiment of the present device in
which heat is transferred bi-directionally using a thermal
superconducting medium, such as described above. Generally, heat is
transferred to and from a thermal superconductor earth source loop
by a thermal superconductor heat exchange coil configured through a
refrigerant loop subsystem with direction of heat flow controlled
by a standard reversing valve system. Specifically, superconductor
geothermal exchange active components are positioned above ground
level 46 and couplable to a geothermal ground loop 48 formed from
thermal superconductor and positioned in a ground loop hole 50. The
ground loop refrigerant or coolant circulating loops of
conventional geoexchange systems are replaced with thermally
superconducting transfer coils that are operable bi-directionally,
resulting in many advantages of efficiency, reduced size, and fewer
components. The ground loop thermal superconductor extends above
ground level where it is covered by insulation 25 and terminated in
a coupler 44. For illustrative purposes, this superconductor may be
in the form of a sealed metal tube as currently available from Qu
Corporation and will be preferred to be in tube form. Alternatively
other available thermal superconductors could be similarly
substituted that may have various forms and cross sections such as
flexible conduits, thin laminate, thin film coated metal etc, that
may be suitable depending on the site and system conditions.
[0046] In the preferred case, the depth of hole D is selected in
combination with the thermal transfer properties of the thermal
superconductor element, the thermal transfer properties of the
ground around hole D and the maximum expected rate of heat transfer
between the heating/cooling system and the ground, in order to
provide a desired heating and cooling capacity for the system. As
in conventional geoexchange systems, the depth of hole 50 may be
greater than is practicable for a single hole, so a plurality of
holes may be substituted to receive a plurality of geothermal heat
exchange elements with an aggregate depth equal to or greater than
the required depth of a single hole. As shown in FIG. 2, this
plurality of geothermal heat exchange units can be joined at or
below coupler 44 in such a manner that they are equally able to
transfer heat to the ground. Due to the improved thermal transfer
properties of the superconductor, the hole size and depth can be
considerably less than conventional geoexchange loops, saving
installation costs and increasing the number of potential sites
that can install geothermal exchange. Persons familiar with the
technology involved here will recognize that hole 50 may
equivalently be a trench in the ground 46, or alternatively the
ground 46 may equivalently be a body of water such as a pond, well,
river, sea or the like and the meaning of ground used herein shall
include body of water. The coupler 44 couples between the ground
loop superconductor 48 and a ground link superconductor segment 40
that transfers heat to and from a heat intensifier system,
providing for ease of installation and conduit routing prior to
connection. Optionally, the coupler may be eliminated in a direct
installation design.
[0047] The superconductor segment 40 extends in an uninsulated
portion 42 to be in thermal contact with a heat exchange segment 68
of a refrigerant loop that functions to circulate heat transferred
to and from the ground loop, as shown in ground loop heat exchanger
66. The refrigerant loop circuit forms a refrigerant transfer path
which includes a compressor 20 having outlet connected to
refrigerant conduit 22 to a reversing valve 28 through conduit 32
to a heat exchange segment 38 in space heat exchanger 36 to a
conduit 60 connected to a directional expander 62 with conduit 64
to a ground heat exchanger 28 connected to a return conduit 34,
through the reversing valve 28 to conduit 21 and an optional
accumulator 23 to a return conduit 24 to the inlet of the
compressor 20. Persons familiar with the technology involved here
will recognize that the space heat exchanger or ground heat
exchanger are interoperable as condenser or evaporator heat
exchangers to provide heating or cooling modes as the reversing
valve 28 is switched from a first position to a second
position.
[0048] When the refrigerant loop as described is filled with a
suitable amount of refrigerant, the compressor can be powered on to
operate the refrigerant heat exchange circuit. In a heating mode
example of the flow of refrigerant, the compressor 20 compresses a
gaseous refrigerant to intensify its heat content, circulates it
through conduit 22 to the space heat exchanger 38 which acts as a
condenser causing the gaseous refrigerant to condense to a liquid
(or partial liquid) before passing through conduit 60 to expander
62 which rapidly expands the liquid in a pressure drop to change
the refrigerant state to cooled vapor which absorbs heat at the
evaporator heat exchanger 68 from the ground loop before passing
through return conduit 34 to optional accumulator 23 (where
remaining liquid is trapped and vaporized) after which the
remaining refrigerant transfers through conduit 24 to complete the
loop at the compressor inlet. This creates a temperature
differential between space heat exchanger 38 and ground heat
exchanger 68. In the preferred case, the refrigerant heat
exchangers are isolated by insulation 25 as shown. The reversing
valve 28 functions to direct the refrigerant flow in alternate
directions, which reverses the thermal function of the heat
exchangers becoming condenser and evaporator in open mode and
evaporator and condenser in closed mode respectively. A thermal
sensor 26 is associated with the medium to be conditioned by space
heat exchange coil 38. A controller 16 is powered by power line 14
and provides power to compressor 20 through control line 18 and
reversing valve 28 through control line 30, as well as control data
to and from thermal sensor 26. Space heat exchange coil 38 can be
configured in any suitable geometric arrangement related to a
structure to improve or optimize heat transfer to a specific
medium. Insulation 25 also preferably covers superconductor
transfer segments outside of coupling connections and heat exchange
sections, to reduce thermal transfer losses.
[0049] The superconductor geothermal exchange system 110 is
operated in either a heating or cooling mode depending on the
difference between the actual measured temperature and a desired
set-point programmed in the thermostatic controller 16. For
example, when the desired temperature is higher than actual
temperature the superconductor geothermal exchange system 110 is
operated in a heating mode. In heating mode, reversing valve 28 is
opened such that space heat exchanger 38 operates as a condenser
giving off heat and ground heat exchanger 68 operates as an
evaporator receiving heat from ground link superconductor 40, while
controller 16 operates compressor 20. Heat is then efficiently
transferred from ground loop 48 to the ground heat exchanger 68,
then efficiently transferred through the refrigerating loop to
space heat exchanger for related heating use. In the cooling mode
example, when the desired temperature is lower than actual
temperature, the superconductor geothermal exchange system 110 is
operated in a cooling mode. In cooling mode, reversing valve 28 is
closed such that space heat exchanger 38 operates as an evaporator
receiving heat and ground heat exchanger 68 operates as a condenser
giving off heat to ground link superconductor 40, while controller
16 operates compressor 20. Heat is then efficiently transferred
from space heat exchanger 68 to ground loop 48 for related cooling
use. The modes may simply switch on/off rather than oscillate
between heating and cooling based on controller programming and
averaging forecasting.
[0050] The refrigerant loop circuit may have additional components
as required to scale for larger energy applications. As known in
the art of conventional heat pump systems, such larger systems may
have receivers, suction accumulators, bulb sensors, thermostatic
expansion metering valves and the like to manage refrigerant flow
through the circuit.
[0051] The superconductor geothermal exchange system 110 attached
to segment 40 above coupler 44 can be enclosed a number of ways,
depending on application. For example, the components shown could
be housed inside one enclosure 12.
[0052] As will be apparent to persons familiar with the technology
involved here, the coupler 44 could equivalently be alternatively
positioned under the ground, above ground outside a structure,
inside a structure but outside the housing 12, or even inside the
housing 12, as selected for best ease of installation. Housing 12
may include ambient vents for convective cooling of the compressor.
A further embodiment of the superconductor geothermal exchange
system 110 can eliminate the coupler 44 by configuring the switch
to have a ground loop receptacle to accept the termination of the
superconductor ground loop 48 such that the ground loop 48 can be
separately installed from the rest of the system.
[0053] By changing the ground loop from a conventional fluid loop
to a superconductor element, geoexchange system 110 eliminates the
energy required to circulate ground loop fluids and as a result
uses less power to operate, making it possible for new improved
components to be utilized. For example, a low power compressor can
be used, such as is available from Danfoss Corporation. In one
embodiment the low power compressor 20 can have power less than
4500 W. In an alternate embodiment the low power compressor 20
requires power less than 1800 W, making it suitable for common
North American household outlets, resulting in more convenient
installation that conventional systems requiring higher power.
[0054] The superconductor geothermal exchange system 110 may
operate from conventional AC grid power, or, alternatively, from a
DC power source such as a hydrogen fuel cell, a solar cell array,
or a wind turbine or the like. In either AC or DC power
embodiments, individual components may be AC or DC powered, with
power conditioners provided as required (not shown), being
delivered to the system 110 already conditioned externally or
delivered requiring additional conditioning, as will be apparent to
persons familiar with the technology involved here. In the DC
powered embodiment in which the components operate on a single
voltage of DC power, low voltage alternative energy power may be
used directly, without power conditioning, thereby reducing energy
loss and potentially eliminating the need for power conditioning
devices.
[0055] Using the preferred thermal superconducting tubes, it is
preferred to have insulation along the length of the superconductor
segments except heat exchanger coil segments or thermal transfer
couplings to other components, to limit heat loss and condensation
buildup. However alternate thermal superconductor embodiments may
have integrated insulating layers or have acceptable transfer loss
such that the superconductor geothermal exchange system 110 is
operable.
[0056] FIG. 2 illustrates an embodiment of system 110 of FIG. 1 in
which the required depth of hole 34 is greater than is practicable
for a single hole. In this embodiment, the single geothermal heat
exchange element is replaced with a plurality of such elements in a
plurality of holes with an aggregate depth equal to or greater than
the required depth of a single hole. This plurality of geothermal
heat exchange units can be joined at or below coupler 44 in such a
manner that they are equally able to transfer heat to the
ground.
[0057] The superconductor geothermal exchange system 110 of FIG. 1
can be configured for air heating and cooling as shown in FIG. 3.
Superconductor geothermal exchange system 120 is designed for air
heating and cooling inside a structure, with the following
modifications and additions. Enclosure 12 has two vented regions to
provide an inlet and outlet for circulated air. Between the two
vented regions is the space heat exchanger coil 38, which is
further insulated by insulation 25 up to the coil. A blower 54 is
positioned in proximity to the space heat exchanger 38 to pull or
push air through the exchanger for heating or cooling, the
preferred position being near the outlet vent region such that air
is pulled over the space heat exchanger 38. The fan can be a low
power, low throughput fan to conserve energy, or alternatively a
variable speed fan. The preferred fan has operating noise less than
45 dB and can be DC powered by an alternative energy source (not
shown). Space heat exchanger 38 may be configured in many possible
designs provided sufficient net surface area is exposed to the air
flow; the illustration of an array of bars substantially
corresponding to the fan diameter is a preferred example.
Alternatively, as is well known in the art of air heat exchangers,
metal fins could be added to increase the surface area of the heat
exchanger. Blower 54 is connected to controller 16 and power line
14 for control of fan operation. In the cooling mode, under some
ambient conditions, condensate will form on the space heat
exchanger 38, and an optional drip tray 56 is shown positioned
below to catch condensate and an optional water drain line 58 is
shown connected to drip tray for runoff disposal.
[0058] The controlled operation of the superconductor geothermal
exchange system 120 is important for user comfort and control of
heating and cooling. Controller 16 may be programmed as a
thermostat controller responding to a temperature sensor 26 (such
as a thermocouple) associated with the space to be heated or
cooled, or as a controller that receives input from a remote
thermostat and sensor associated with the space (not shown). The
controller is shown within the housing 12, but may alternatively be
in any suitable location provided it is in communication with the
blower and temperature sensor. While the simplest implementation is
one temperature measurement, to persons familiar with the
technology involved here, multiple temperature measurements could
be weighted or averaged for the purpose of feedback set points in
the controller 16. In the case of a multi-speed fan, alternatively
a second temperature sensor could be positioned on or near the
space heat exchanger 38 to determine the initial fan speed for
faster cooling. Unlike conventional central geothermal heat pumps,
which are large, noisy and require greater power than available
from a standard household outlet, the air exchange subsystem in
enclosure 60 can be operated from a standard power outlet, anywhere
in the house, quietly and in a small form factor housing. The
housing 60 for air exchange subsystem, may be positioned anywhere
within the interior room to be cooled or heated, and does not have
to be near an exterior wall or window. Preferably the housing is
positioned to provide optimum air mixing and heating for the
room.
[0059] Operating modes are similar to those described for FIG. 1,
with the additional mode of operating the blower in combination
with operating the intensifying compressor for improving the rate
of heat exchange with the air space to be conditioned. With the
controller 16 set to a desired room temperature T1, via a manual
input (not shown), or a remote control input, or a second remote
thermostat (not shown) in communication with the controller 16, the
controller senses existing room temperature T2 and if higher or
lower than T1, switches reversing valve 28 to create appropriate
heating or cooling circuit, operates the compressor 20 to circulate
heated refrigerant and operates blower 54 to circulate air until
the temperature reaches T1. Alternatively, as common in the art,
various thresholding or smoothing processes can be programmed to
avoid jitter and determine when to switch the blower 54 on or off.
In the example of a multi-speed blower, the blower speed can be
programmed to change in response to the rate of change of existing
temperature T2, in addition to on or off. The superconductor
geothermal exchange system 120 can be programmed to operate for
inputs that act as related proxies for associated interior
temperature and that have a known characterized relationship to
temperature.
[0060] A further embodiment of the superconductor geothermal
exchange system 120 can eliminate the coupler 44 by configuring the
switch to have a ground loop receptacle portion to accept the
termination of the superconductor ground loop 48, such that the
ground loop 48 can be separately installed from the rest of the
system. Persons familiar with the technology involved here will
recognize that that there are many equivalent designs to couple the
ground loop superconductor to the switch including intermediate
coupler segments.
[0061] The superconductor geothermal exchange systems of FIGS. 1
and 2 have many advantages that solve the problems described in the
background, due to the substantial efficiency increase relative to
existing geoexchange solutions. These efficiency gains result in
coefficient of performance of greater than 2 and potentially as
high as 5 or more (relative to the efficiency of an electric
resistance wire which is generally understood to have a coefficient
of performance of 1), beyond the limits of conventional
geoexchange. First, the hole depth of the geothermal earth source
loop can be less than conventional ground loop depth, reducing
costs and increasing qualifying sites. Second, by reducing the
power requirements of the compressor and eliminating ground loop
circulating pumps, the power requirements of the geothermal cooling
device are substantially less than conventional geothermal exchange
units, whether central or for a single room, and permit the
installation and operation on normal household circuits such as a
15 Ampere rated outlet. Third, the lightweight and small size of
the exchange coil housing relative to existing solutions, permits
easy installation in a wide range of locations and even
installations of individual exchange units in multiple rooms of a
residence interior. Fourth, due to eliminating ground loop
refrigerant and associated high power circulation pumps, system
lifetimes are extended beyond conventional geoexchange.
[0062] The superconductor geothermal exchange system 110 of FIG. 1
can be configured for heating and cooling a secondary liquid such
as water, liquid solutions and the like, as shown in FIGS. 4, 5 and
6. In FIG. 4, superconductor geothermal exchange system 130 is
designed for heating and cooling a secondary fluid 82 for use
inside a structure, for example to heat domestic water or to heat
water in a hydronic radiant floor, with the following modifications
and additions. Heat exchanger element 38 is immersed in a fluid 82
in tank 80 for the purpose of transferring heat to and from fluid
82. Fluid 82 is stored in tank 80 in a volume resulting in a
thermal mass and having storage temperature measured by sensor 84
connected to controller 16. The space heat exchanger 38 is arranged
in the tank in contact with the exchange fluid 82, as shown. The
fluid in the tank is circulated by a pump (not shown) out to a
remote exchange location through outlet 88 and returned to the tank
80 through inlet 86 with resultant change in fluid temperature. For
this case, the remote exchange may be fluid-to-air, fluid-to-liquid
or fluid to solid thermal mass and have an associated temperature
sensor (not shown). Controller 16 is connected to operate power
pump (not shown) for circulation of secondary fluid, in combination
with operating the superconductor geothermal exchange system in
heating or cooling modes as previously described.
[0063] FIG. 5 shows another alternative configuration of geothermal
exchange system 130 in which a fluid heat exchanger is configured
to provide indirect heat transfer to and from an auxiliary fluid
loop. In this configuration, heat exchanger 38 is immersed in a
non-circulating heat transfer fluid in a tank 85. A secondary
circulating fluid enters tank 85 through fluid inlet 81 and passes
through a secondary heat exchange loop, absorbing heat from heat
transfer fluid (in the heating mode) or giving up heat (in the
cooling mode) before exiting tank 85 through fluid outlet 83.
[0064] FIG. 6 shows another alternative configuration of geothermal
exchange system 130 in which fluid heat exchanger 104 is configured
to provide direct thermal transfer between heat exchange element 38
and a fluid loop 75 through thermal contact between the element and
loop. In this configuration, a fluid (not shown) such as water, a
liquid solution or a refrigerant is circulated by a separate system
(not shown) coupled to inlet 81 and outlet 83 and passes through
fluid loop 75, transferring heat through the walls of fluid loop 75
walls, to or from heat exchange element 38 directly. As will be
apparent to persons familiar with the technology involved here,
such thermal contact can be provided by metal-metal contact or by
contact with an intermediate, localized heat transfer component
such as a thermal paste and the like.
[0065] The above-ground components of the geothermal exchange
systems described in FIGS. 1 to 6 can be grouped in plurality of
separate housings as shown in FIGS. 7 and 8. FIG. 7a illustrates
one embodiment of a such split system in which remote housing 92
encloses the space heat exchanger 38, blower 54 expansion valve 62a
and associated inlet and outlet conduit to transfer the incoming
and outgoing refrigerant with the other components in the
refrigerant loop, and control line 30a to operate the fan 54.
Optionally, drip tray and line 56, 58 and temperature sensor 26 may
be included. The expander may be either located in enclosure 12 as
expander 62 or optionally in housing 92 as shown as expander 62a.
There are three advantages to a split housing. First, installation
may be made easier by placing the elements coupled to the ground
superconductor outside. Second, there is an advantage to housing
the noisy components such as the compressor in a separate housing
such that the noise level in the heating space is reduced. Third,
as the compressor produces heat while operating, there is an
advantage to having it outside rather than having the extra heat
discharged into the space being cooled, reduce efficiency of the
cooling mode. Further, the housing 12 could be located centrally in
a structure, with enclosure 52 located remotely in a space to be
heated or cooled, as shown by the example of enclosure 92 in FIG.
7b. Alternatively, housing 12 could be located exterior to a
structure and connected through superconductor transfer segment 38
to enclosure 52 located inside the structure to be heated or
cooled.
[0066] FIG. 8 illustrates an alternate exchange configuration in
which heat exchanger 66 and related components are enclosed in
enclosure 94 such that heat exchange between ground loop 48 and the
refrigerant loop is accomplished outside enclosure 12, allowing
ground heat exchanger 66 to be located at any point below, at or
above ground level, making system installation more flexible.
Optional connectors 96 and 96a enable simplified interconnection of
system components in some applications.
[0067] FIG. 9 illustrates an embodiment of the present device in
which heat is transferred in a heating only mode using a thermal
superconducting medium, such as described above, for a
superconductor geothermal heating device 150. Generally, heat is
transferred from a thermal superconductor earth source loop by a
thermal superconductor heat exchange coil configured through a
refrigerant loop subsystem. Specifically, superconductor geothermal
exchange active components are positioned above ground level 46 and
couplable to a geothermal ground loop 48 formed from thermal
superconductor and positioned in a ground loop hole 50. The ground
loop refrigerant or coolant circulating loops of conventional
geoexchange systems are replaced with thermally superconducting
transfer coils that are operable bi-directionally, resulting in
many advantages of efficiency, reduced size, and fewer components.
The ground loop thermal superconductor extends above ground level
where it is covered by insulation 25 and terminated in a coupler
44. For illustrative purposes, this superconductor may be in the
form of a sealed metal tube as currently available from Qu
Corporation and will be preferred to be in tube form. Alternatively
other available thermal superconductors could be similarly
substituted that may have various forms and cross sections such as
flexible conduits, thin laminate, thin film coated metal etc, that
may be suitable depending on the site and system conditions.
[0068] The superconductor segment 40 extends to be in thermal
contact to an evaporator exchanger 68 of a refrigerant loop that
functions to circulate heat transferred from the ground loop. The
refrigerant loop circuit forms a refrigerant transfer path which
includes a compressor 20 having outlet connected to refrigerant
conduit 22 to condenser heat exchanger 74 to a conduit 32 connected
to an expander 62 with conduit 64 to evaporator heat exchanger 72
connected to a return conduit 34, through an optional accumulator
23 to a return conduit 24 to the inlet of the compressor 20.
[0069] When the refrigerant loop as described is filled with a
suitable amount of refrigerant, the compressor may be powered on to
operate the refrigerant heat exchange circuit. In a the heating
mode, the compressor 20 compresses a gaseous refrigerant to
intensify its heat content, circulates it through conduit 22 to the
condenser heat exchanger 74 where the hot refrigerant vapor gives
up heat and condenses to a liquid or partial liquid before passing
through conduit 60 to expander 62 where the liquid refrigerant is
expanded in a pressure drop to change state, becoming cooled vapor
which enters evaporator heat exchanger 72 and absorbs heat from the
ground loop before passing through return conduit 34 to optional
accumulator 23 (where remaining liquid is trapped and vaporized)
before the refrigerant transfers through conduit 24 to complete the
loop at the compressor inlet. This creates a temperature
differential between the condenser heat exchanger 74 and evaporator
heat exchanger 72. In the preferred case, heat exchangers 74 and 72
are isolated by insulation 25 (not shown.) A thermal sensor 26 is
associated with the medium to be conditioned by condenser heat
exchanger 74. A controller 16 is powered by power line 14 and
provides power to compressor 20 and reversing valve 28, as well as
control data to and from thermal sensor 26. Condenser heat
exchanger 74 can be configured in any suitable geometric
arrangement related to a structure to improve or optimize heat
transfer to a specific medium. Insulation 25 also preferably covers
superconductor transfer segments outside of coupling connections
and heat exchange sections, to reduce thermal transfer losses.
[0070] The superconductor geothermal exchange system 150 is
operable depending on the difference between the actual measured
temperature and a desired set-point programmed in the thermostatic
controller 16. For example, when the desired temperature is higher
than actual temperature the superconductor geothermal exchange
system 150 is operated. Heat is then efficiently transferred from
ground loop 48 to the evaporator heat exchanger 72, then
efficiently transferred through the refrigerating loop to condenser
heat exchanger for related heating use.
[0071] The superconductor geothermal exchange system 150 attached
to segment 40 above coupler 44 can be enclosed a number of ways,
depending on application. For example, the components as shown
could be housed inside one enclosure 12. Alternatively thermal
superconductor segments 40 and 42 can be installed at a later time.
As will be apparent to persons familiar with the technology
involved here, the coupler 44 could equivalently be alternatively
positioned under the ground, above ground outside a structure,
inside a structure but outside the housing 12, or even inside the
housing 12, as selected for best ease of installation. Housing 12
may include ambient vents for convective cooling of the compressor.
A further embodiment of the superconductor geothermal exchange
system 150 can eliminate the coupler 44 by configuring the switch
to have a ground loop receptacle to accept the termination of the
superconductor ground loop 48 such that the ground loop 48 can be
separately installed from the rest of the system.
[0072] The superconductor geothermal heating device 150 of FIG. 9,
can be configured for air heating as shown in FIG. 10.
Superconductor geothermal heating device 160 is designed for air
heating inside a structure, with the following modifications and
additions. Enclosure 12 has two vented regions to provide an inlet
and outlet for circulated air. Between the two vented regions is
the evaporator exchanger 38, which is further insulated by
insulation 25 up to the coil. A blower 54 is positioned in
proximity to the evaporator heat exchanger 74 to pull or push air
through the exchanger for heating, the preferred position being
near the outlet vent region such that air is pulled over heat
exchanger 74. The fan can be a low power, low throughput fan to
conserve energy, or alternatively a variable speed fan. The
preferred fan has operating noise less than 45 dB and can be DC
powered by an alternative energy source (not shown). Evaporator
heat exchanger 74 may be configured in many possible designs
provided sufficient net surface area is exposed to the air flow;
the illustration of an array of bars substantially corresponding to
the fan diameter, is a preferred example. Alternatively, as is well
known in the art of air heat exchangers, metal fins could be added
to increase the surface area of the heat exchanger. Blower 54 is
connected to controller 16 and power line 14 for control of fan
operation.
[0073] The controlled operation of the superconductor geothermal
exchange system 160 is important for user comfort and control of
heating. Controller 16 may be programmed as a thermostat controller
responding to a temperature sensor 26 (such as a thermocouple)
associated with the space to be heated, or as a controller that
receives input from a remote thermostat and sensor associated with
the space (not shown). The controller is shown within the housing
12, but may alternatively be in any suitable location provided it
is in communication with the blower and temperature sensor. While
the simplest implementation is one temperature measurement, persons
familiar with the technology involved here will recognize that
multiple temperature measurements could be weighted or averaged for
the purpose of feedback set points in the controller 16. In the
case of a multi-speed fan, alternatively a second temperature
sensor could be positioned on or near the space heat exchanger 74
to determine the initial fan speed for faster heating. Unlike
conventional central geothermal heat pumps, which are large, noisy
and require greater power than available from a standard household
outlet, the air exchange subsystem in enclosure 60 can be operated
from a standard power outlet, anywhere in the house, quietly and in
a small form factor housing. The housing 60 for air exchange
subsystem, may be positioned anywhere within the interior room to
be heated, and does not have to be near an exterior wall or window.
Preferably the housing is positioned to provide optimum air mixing
and heating or cooling for the room.
[0074] Operating mode is similar as described for FIG. 9, with the
additional mode of operating the blower in combination with
operating the compressor for improving the rate of heat exchange
with the air space to be conditioned. With the controller 16 set to
a desired room temperature T1, via a manual input (not shown), or a
remote control input, or a second remote thermostat (not shown) in
communication with the controller 16, the controller senses
existing room temperature T2 and if lower than T1, operates the
compressor 20 to circulate heated refrigerant and operates blower
54 to circulate air until the temperature reaches T1.
Alternatively, as common in the art, various thresholding or
smoothing processes can be programmed to avoid jitter and determine
when to switch the blower 54 on or off. In the example of a
multi-speed blower, the blower speed can be programmed to change in
response to the rate of change of existing temperature T2, in
addition to on or off. The superconductor geothermal exchange
system 160 can be programmed to operate for inputs that act as
related proxies for associated interior temperature and that have a
known characterized relationship to temperature.
[0075] A further embodiment of the superconductor geothermal
exchange system 160 can eliminate the coupler 44 by configuring the
evaporator heat exchanger 68 to have a receptacle portion to accept
the termination of the superconductor ground loop 48, such that the
ground loop 48 can be separately installed from the rest of the
system. Persons familiar with the technology involved here will
recognize that that there are many equivalent designs to couple the
ground loop superconductor to the switch including intermediate
coupler segments.
[0076] The superconductor geothermal heating devices of FIGS. 9 and
10 have many advantages that solve the problems described in the
background, due to the substantial efficiency increase relative to
existing geothermal heating solutions. These efficiency gains
result in coefficient of performance of greater than 2 and
potentially as high as 5 or more, beyond the limits of conventional
geothermal heating. First, by increasing system efficiency, the
hole depth of the geothermal earth source loop can be less than
conventional ground loop depth, reducing costs and increasing
qualifying sites. Second, by reducing the power requirements of the
compressor and eliminating ground loop circulating pumps, the power
requirements of the geothermal cooling device are substantially
less than conventional geothermal exchange units, whether central
or for a single room, and permit the installation and operation on
normal household circuits such as a 15 Ampere rated outlet. Third,
the lightweight and small size of the exchange coil housing
relative to existing solutions, permits easy installation in a wide
range of locations and even installations of individual exchange
units in multiple rooms of a residence interior. Fourth, due to
eliminating ground loop refrigerant and associated high power
circulation pumps, system lifetimes are extended beyond
conventional geoexchange.
[0077] The superconductor geothermal heating device 150 of FIG. 9,
can be configured for heating a secondary liquid such as water,
liquid solutions and the like, as shown in FIGS. 11, 12 and 13. In
FIG. 11, superconductor geothermal exchange system 170 is designed
for heating and cooling a secondary exchange fluid 82 for use
inside a structure, with the following modifications and additions
to heating device 150. Heat exchanger element 38 is immersed in a
fluid 82 in tank 80 for the purpose of transferring heat to and
from fluid 82. Fluid 82 is stored in tank 80 in a volume resulting
in a thermal mass and having storage temperature measured by sensor
84 connected to controller 16 through control line 90. The space
heat exchanger 38 is arranged in the tank in contact with the
exchange fluid 82, as shown. The fluid in the tank is circulated by
a pump (not shown) out to a remote exchange location through outlet
88 and returned to the tank 80 through inlet 86 with resultant
change in fluid temperature. For this case, the remote exchange may
be fluid-to-air, fluid-to-liquid or fluid to solid thermal mass and
have an associated temperature sensor (not shown). Controller 16 is
connected to operate power pump (not shown) for circulation of
secondary fluid, in combination with operating the superconductor
geothermal exchange system in heating or cooling modes as
previously described.
[0078] Alternatively, as shown in FIG. 12, a fluid heat exchanger
can be configured to provide indirect heat transfer to and from an
auxiliary fluid loop. In this configuration, heat exchanger 38 is
immersed in a non-circulating heat transfer fluid in a tank 85. A
secondary circulating fluid (not shown) enters tank 85 through
fluid inlet 81 and passes through heat exchange loop 89, absorbing
heat from heat transfer fluid 87 (in the heating mode) or giving up
heat (in the cooling mode) before exiting tank 85 through fluid
outlet 83.
[0079] FIG. 13 shows another alternative configuration in which the
fluid heat exchanger is configured in tank 104 to provide direct
thermal transfer between heat exchange element 38 and a fluid loop
75 through thermal contact between the two elements. In this
configuration, a fluid (not shown) such as water, a liquid solution
or a refrigerant is circulated by a separate system (not shown) and
passes through fluid loop 75, transferring heat through the walls
of fluid loop 75 walls, to or from heat exchange element 38
directly. As will be apparent to persons familiar with the
technology involved here, such thermal contact can be provided by
metal-metal contact or by contact with an intermediate, localized
heat transfer component such as a thermal paste and the like.
Exchange fluid is typically in exchange with a second liquid or air
exchanger for use in heating such as floor or radiator heating,
domestic water heating. Fluid may alternatively be distributed and
circulated for distributed exchange.
[0080] The above-ground components of the geothermal exchange
systems described in FIGS. 9 to 13 can be grouped in plurality of
separate housings as shown in FIGS. 14a, 14b and 15. FIG. 14a
illustrates an embodiment in which the condenser exchanger is
located remotely in housing 92. Housing 92 encloses the condenser
exchanger 74, blower 54, expansion valve 62a and associated inlet
and outlet conduit to transfer the incoming and outgoing
refrigerant with the other components in the refrigerant loop.
Control line 30a is connected between the two housings for
controlling the fan 54. Optionally, temperature sensor 26 may be
included. There are two advantages to a split housing. First,
installation may be made easier by placing the elements coupled to
the ground superconductor outside. Second, there is an advantage to
housing the noisy components such as compressor in a separate
housing such that the noise level in the heating and cooling space
is reduced. Further, the housing 12 could be located centrally in a
structure, with enclosure 52 located remotely in a space to be
heated, as shown by the example of enclosure 92 in FIG. 14b.
Alternatively, housing 12 could be located exterior to a structure
and connected through superconductor transfer segment 38 to
enclosure 52 located inside the structure to be heated. Similarly,
as shown in FIG. 15, split housing enclosures can be configured for
alternate exchange configurations with the appropriate relocation
of heat exchange related components. In this figure, heat exchanger
66 and related components are enclosed in enclosure 94 such that
heat exchange between ground loop 48 and the refrigerant loop
happens outside enclosure 12, allowing ground heat exchanger 66 to
be located at any suitable point below, at or above ground level,
making system installation more flexible. Optional connectors 96
and 96a enable simplified interconnection of system components in
some applications.
[0081] FIG. 16 illustrates an embodiment of the present device in
which heat is transferred in a cooling only mode, using a thermal
superconducting medium such as described above, for a
superconductor geothermal cooling device 190. Generally, heat is
transferred to a thermal superconductor earth source loop by a
thermal superconductor heat exchange coil configured through a
refrigerant loop subsystem. Specifically, superconductor geothermal
exchange active components are positioned above ground level 46 and
couplable to a geothermal ground loop 48 formed from thermal
superconductor and positioned in a ground loop hole 50. The ground
loop refrigerant or coolant circulating loops of conventional
geoexchange systems are replaced with thermally superconducting
transfer coils that are operable bi-directionally, resulting in
many advantages of efficiency, reduced size, and fewer components.
The ground loop thermal superconductor extends above ground level
where it is covered by insulation 25 and terminated in a coupler
44. For illustrative purposes, this superconductor may be in the
form of a sealed metal tube as currently available from Qu
Corporation and will be preferred to be in tube form. Alternatively
other available thermal superconductors could be similarly
substituted that may have various forms and cross sections such as
flexible conduits, thin laminate, thin film coated metal etc, that
may be suitable depending on the site and system conditions.
[0082] The superconductor segment 40 extends to be in thermal
contact to a condenser exchanger 68 of a refrigerant loop that
functions to circulate heat to the ground loop. The refrigerant
loop circuit forms a refrigerant transfer path which includes a
compressor 20 having outlet connected to refrigerant conduit 22 to
a condenser exchanger 76 to a conduit 32 connected to an expander
62 with conduit 64 to an evaporator exchanger 78 connected to a
return conduit 34, through an optional accumulator 23 to a return
conduit 24 to the inlet of the compressor 20.
[0083] When the refrigerant loop as described is filled with a
suitable amount of refrigerant, the refrigerant heat exchange
circuit is operated by powering the compressor. In a cooling mode,
the compressor 20 compresses a gaseous refrigerant to intensify its
heat content, circulates it through conduit 22 to the condenser
exchanger 76 where it gives up heat to the ground loop acting as a
condenser, and then passes through conduit 60 to expander 62 which
rapidly expands liquid in a pressure drop to change the refrigerant
state to cooled vapor which absorbs heat at the evaporator
exchanger 78 before passing through return conduit 34 to optional
accumulator 23 (where remaining liquid is trapped and vaporized)
and remaining refrigerant transfers through conduit 24 to complete
the loop at the compressor inlet. This creates a temperature
differential between evaporator exchanger 78 and condenser
exchanger 76. In the preferred case, the refrigerant heat
exchangers are isolated by insulation 25 as shown. A thermal sensor
26 is associated with the medium to be conditioned by evaporator
exchanger 78. A controller 16 is powered by power line 14 and
provides power to compressor 20 and reversing valve 28, as well as
control data to and from thermal sensor 26. Evaporator exchanger 78
can be configured in any suitable geometric arrangement related to
a structure to improve or optimize heat transfer to a specific
medium. Insulation 25 also preferably covers superconductor
transfer segments outside of coupling connections and heat exchange
sections, to reduce thermal transfer losses.
[0084] The superconductor geothermal cooling device 190 is
controlled depending on the difference between the actual measured
temperature and a desired set-point programmed in the thermostatic
controller 16. For example, when the desired temperature is lower
than actual temperature the superconductor geothermal cooling
device 190 is operated in a cooling mode. In cooling mode, heat is
collected at the condenser exchanger, transferred through the
refrigerating loop then efficiently transferred to ground loop 48
from the condenser exchanger 76, for related cooling use.
[0085] The superconductor geothermal cooling device 190 attached to
segment 40 above coupler 44 can be enclosed a number of ways,
depending on application. For example, the components as shown
could be housed inside one enclosure 12. Alternatively thermal
superconductor segments 40 and 42 can be installed at a later time.
As will be apparent to persons familiar with the technology
involved here, the coupler 44 could equivalently be alternatively
positioned under the ground, above ground outside a structure,
inside a structure but outside the housing 12, or even inside the
housing 12, as selected for best ease of installation. Housing 12
may include ambient vents for convective cooling of the compressor.
A further embodiment of the superconductor geothermal cooling
device 190 can eliminate the coupler 44 by configuring the switch
to have a ground loop receptacle to accept the termination of the
superconductor ground loop 48 such that the ground loop 48 can be
separately installed from the rest of the system.
[0086] The superconductor geothermal cooling device 190 of FIG. 16,
can be configured for air cooling as shown in FIG. 17.
Superconductor geothermal cooling system 200 is designed for air
cooling inside a structure, with the following modifications and
additions. Enclosure 12 has two vented regions to provide an inlet
and outlet for circulated air. Between the two vented regions is
the evaporator exchanger 78, which is further insulated by
insulation 25 up to the coil. A blower 54 is positioned in
proximity to the evaporator exchanger 78 to pull or push air
through the exchanger for cooling, the preferred position being
near the outlet vent region such that air is pulled over the
evaporator exchanger 78. The fan can be a low power, low throughput
fan to conserve energy, or alternatively a variable speed fan. The
preferred fan has operating noise less than 45 dB and can be DC
powered by an alternative energy source (not shown). Evaporator
exchanger 78 may be configured in many possible designs provided
sufficient net surface area is exposed to the air flow; the
illustration of an array of bars substantially corresponding to the
fan diameter, is a preferred example. Alternatively, as is well
known in the art of air heat exchangers, metal fins could be added
to increase the surface area of the heat exchanger. Blower 54 is
connected to controller 16 and power line 14 for control of fan
operation. Under some ambient conditions, condensate will form on
the evaporator exchanger 78, and an optional drip tray 56 is shown
positioned below to catch condensate and an optional water drain
line 58 is shown connected to drip tray for runoff disposal.
[0087] The controlled operation of the superconductor geothermal
cooling device 200 is important for user comfort and control of
cooling. Controller 16 may be programmed as a thermostat controller
responding to a temperature sensor 26 (such as a thermocouple)
associated with the space to be heated, or as a controller that
receives input from a remote thermostat and sensor associated with
the space (not shown). The controller is shown within the housing
12, but may alternatively be in any suitable location provided it
is in communication with the blower and temperature sensor. While
the simplest implementation is one temperature measurement, persons
familiar with the technology involved here will recognize that
multiple temperature measurements could be weighted or averaged for
the purpose of feedback set points in the controller 16. In the
case of a multi-speed fan, alternatively a second temperature
sensor could be positioned on or near the space heat exchanger 38
to determine the initial fan speed for faster cooling. Unlike
conventional central geothermal heat pumps, which are large, noisy
and require greater power than available from a standard household
outlet, the air exchange subsystem in enclosure 12 can be operated
from a standard power outlet, anywhere in the house, quietly and in
a small form factor housing. Preferably the housing is positioned
to provide optimum air mixing and cooling for the room.
[0088] Operating modes are similar as described for FIG. 16, with
the additional mode of operating the blower in combination with
operating the compressor for improving the rate of heat exchange
with the air space to be conditioned. With the controller 16 set to
a desired room temperature T1, via a manual input (not shown), or a
remote control input, or a second remote thermostat (not shown) in
communication with the controller 16, the controller senses
existing room temperature T2 and if higher than T1, operates the
compressor 20 to circulate heated refrigerant and operates blower
54 to circulate air until the temperature reaches T1.
Alternatively, as common in the art, various thresholding or
smoothing processes can be programmed to avoid jitter and determine
when to switch the blower 54 on or off. In the example of a
multi-speed blower, the blower speed can be programmed to change in
response to the rate of change of existing temperature T2, in
addition to on or off, such that cooling device 200 maintains
optimal thermal comfort in a space while minimizing fan noise,
compressor noise and system cycling. The superconductor geothermal
cooling device 200 can also be programmed to operate for inputs
that act as related proxies for associated interior temperature and
that have a known characterized relationship to temperature.
[0089] A further embodiment of the superconductor geothermal
cooling device 200 can eliminate the coupler 44 by configuring the
condenser exchanger 76 to have a receptacle portion to accept the
termination of the superconductor ground loop 48, such that the
ground loop 48 can be separately installed from the rest of the
system. Persons familiar with the technology involved here will
recognize that that there are many equivalent designs to couple the
ground loop superconductor to the switch including intermediate
coupler segments.
[0090] The above-ground components of the geothermal exchange
systems described in FIGS. 16 and 17 can be grouped in plurality of
separate housings as shown in FIGS. 18a, 18b and 19. FIG. 18a
illustrates an embodiment in which the condenser exchanger is
located remotely in housing 92. Housing 92 encloses the condenser
exchanger 74, blower 54, expansion valve 62 and associated inlet
and outlet conduit to transfer the incoming and outgoing
refrigerant with the other components in the refrigerant loop.
Optionally, drip tray and line 56, 58 and temperature sensor 26 may
be included. There are three advantages to a split housing. First,
installation may be made easier by placing the elements coupled to
the ground superconductor outside. Second, there is an advantage to
housing the noisy components such as compressor in a separate
housing such that the noise level in the heating and cooling space
is reduced. Third, as the compressor produces heat while operating,
there is an advantage to having it outside rather than having the
extra heat reduce effectiveness of cooling the space in cooling
mode. Further, the housing 12 could be located centrally in a
structure, with enclosure 52 located remotely in a space to be
heated, as shown by the example of enclosure 92 in FIG. 18b.
Alternatively, housing 12 could be located exterior to a structure
and connected through superconductor transfer segment 38 to
enclosure 52 located inside the structure to be heated. Similarly,
as shown in FIG. 19, split enclosures can be configured for
alternate exchange configurations with the appropriate relocation
of heat exchange related components. In this figure, heat exchanger
66 and related components are enclosed in enclosure 94 such that
heat exchange between ground loop 48 and the refrigerant loop
happens outside enclosure 12, allowing ground heat exchanger 66 to
be located at any suitable point below, at or above ground level,
making system installation more flexible. Optional connectors 96
and 96a enable simplified interconnection of system components in
some applications.
[0091] The superconductor geothermal cooling devices of FIGS. 16
through 19 have many advantages that solve the problems described
in the background, due to the substantial energy efficiency and
cost efficiency increases relative to existing geothermal cooling
solutions. These efficiency gains result in coefficient of
performance of greater than 2 and potentially as high as 5 or more,
beyond the limits of conventional geothermal cooling. First, the
hole depth of the geothermal earth source loop can be less than
conventional ground loop depth, reducing costs and increasing
qualifying sites. Second, by reducing the power requirements of the
compressor and eliminating ground loop circulating pumps, the power
requirements of the geothermal cooling device are substantially
less than conventional geothermal exchange units, whether central
or for a single room, and permit the installation and operation on
normal household circuits such as a 15 Ampere rated outlet. Third,
the lightweight and small size of the exchange coil housing
relative to existing solutions, permits easy installation in
buildings. Fourth, due to eliminating ground loop refrigerant and
associated high power circulation pumps, system lifetimes are
extended beyond conventional geoexchange.
[0092] The thermal superconductor geoexchange systems and heating
and cooling devices described herein are couplable or connectable
to a thermal superconductor element. The systems may be assembled
from subsystems having no thermal superconductor elements, but with
the addition of a superconductor heat exchange interconnect
thermally coupled to ground loop heat exchanger 68, 72 or 76. The
heat exchange interconnect preferably limits increases in heat
transfer resistance to less than 15% when connected to a thermal
superconductor, and is easily coupled to a tube or rod shaped
thermal superconductor.
[0093] Examples of such interconnections are shown in FIGS. 20a,
20b and 20c. FIG. 20a illustrates a geothermal heating and cooling
system 200 couplable to a superconducting earth source ground loop
through superconductor heat exchange interconnect 102. FIG. 20b
illustrates one embodiment of such a ground source heat exchanger
incorporating superconductor heat exchange interconnect 102 in the
form of a tubular opening in a metal block 66 that is coupled with
heat exchanger through ports 34 and 64. This tubular opening has a
diameter slightly larger than corresponding uninsulated thermal
superconductor tube 42, such that when thermal superconductor tube
42 is inserted in the hole, it directly contacts the surface of the
metal block and heat is transferred between the superconductor tube
and the heat exchanger. The tube may have securing fasteners 108 on
at least one side to maintain the thermal superconductor from
moving. FIG. 20c shows an alternate embodiment of the coupling
shown in FIG. 20b. In this embodiment, the diameter of the tubular
opening that forms superconductor heat exchange interconnect 102 is
significantly larger than the corresponding thermal superconductor
tube 42 such that when the superconductor tube is inserted in the
hole, a gap is formed between the superconductor tube and the walls
of the tubular hole. When the gap is filled with a thermal paste,
heat is transferred between the thermal superconductor tube and the
heat exchanger through the thermal paste. Persons familiar with the
technology involved here will recognize that it may be necessary or
desirable to provide a seal at the opening of superconductor heat
exchange interconnect 102 to keep the thermal paste in the gap
between the thermal transfer surfaces.
[0094] FIG. 21 shows two alternative configurations for coupling
superconductor heat exchange interconnect 102 and ground loop heat
exchangers 68, 72 or 76. In FIG. 21a, a heat exchange coil 68 is
arranged in a tight wound coil around superconductor heat exchange
interconnect 102b which is configured as a metal tube having an
opening to receive a tubular superconductor segment, and couples
through ports 34b and 64b. In FIG. 21b, the heat exchanger is
configured as a sleeve with a cavity 106 suitable for receiving a
thermal superconductor tube, with the refrigerant flowing through
the sleeve to transfer heat through the inner sleeve surface and
coupled to the refrigerant loop through ports 34c and 64c. At the
sleeve cavity opening, there maybe a refrigerant collector to
couple the refrigerant to the exchange loop. The interconnect may
have multiple sleeve openings for coupling multiple thermal
superconductor ground loops. The thermal interconnect will be
preferably rigid to maintain uniform flow conditions for the
refrigerant.
[0095] FIG. 22 illustrates a geothermal heating system 210 suitable
for coupling to a superconducting earth source ground loop through
superconductor heat exchange interconnect 102 in the same manner
described in FIG. 20 for system 200. System 210, when coupled to
superconductor ground loop, can be operated and additionally
configured with reference to FIGS. 9-15.
[0096] FIG. 23 illustrates a geothermal cooling system 220 suitable
for coupling to a superconducting earth source ground loop through
superconductor heat exchange interconnect 102 in the same manner
described in FIG. 20 for system 200. System 220, when coupled to
superconductor ground loop, can be operated and additionally
configured with reference to FIGS. 16-19.
[0097] In these examples and embodiments described, insulation has
been shown on superconductor segments which function to transfer
heat internally from one location to another, and insulation is not
shown on ends of these segments which function to transfer heat to
air, fluids or other or other system components. This is the
preferred example, whether or not explicitly stated in figure
descriptions or numbered on drawings. However, as noted previously,
the superconductor geothermal cooling devices described will
operate with no insulation or with some transfer lines insulated or
combinations of insulated or uninsulated portions of the
superconductors thereof.
[0098] In these examples housing has been described as split
housing in a preferred case, however it will be appreciated that
the various embodiments can be integrated into existing structures
or enclosed in a single housing.
[0099] Although particular embodiments of the invention have been
described by way of example, it will be appreciated that additions,
modifications and alternatives thereto may be envisaged. The scope
of the present disclosure includes any novel feature or combination
of features disclosed therein either explicitly or implicitly or
any generalization thereof irrespective of whether or not it
relates to the claimed invention or mitigates any or all of the
problems addressed by the present invention. The applicant hereby
gives notice that new claims may be formulated to such features
during the prosecution of this application or of any such further
application derived there from. In particular, with reference to
the appended claims, features from dependent claims may be combined
with those of the independent claims and features from respective
independent claims may be combined in any appropriate manner and
not merely in the specific combinations enumerated in the
claims.
* * * * *