DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Application Status
This office action is in response to amendments/arguments filed on November 21, 2025. Applicant has amended Claims 1, 10, and 20. Claims 1 – 20 are currently pending.
Response to Arguments
Applicant’s arguments have been fully considered.
Previous 112 interpretations stand.
Previous double patenting rejections stand.
With regards to the previous 103 rejections, applicant amended the independent claims to add that the HSA comprises fresh or salt-water bearing sedimentary rock, arguing that Willems does not teach this feature. Examiner respectfully disagrees. Willems explicitly teaches extracting hot water from hot sedimentary aquifers (see abstract and section 1 introduction on Page 54, “hot sedimentary aquifers”). Hot sedimentary aquifers, by definition, are sedimentary rock formations comprising pockets/layers of water. On Page 56, Willems teaches water density of 1050 kg/m^3, and uses a salinity dependent viscosity variable in one of the numerical approximations, indicating that the water is briny and comprises some salt content. Previous 103 rejections stand.
Claim Interpretations Under 35 USC § 112
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph:
An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
Use of the word “means” (or “step for”) in a claim with functional language creates a rebuttable presumption that the claim element is to be treated in accordance with 35 U.S.C. 112(f) (pre-AIA 35 U.S.C. 112, sixth paragraph). The presumption that 35 U.S.C. 112(f) (pre-AIA 35 U.S.C. 112, sixth paragraph) is invoked is rebutted when the function is recited with sufficient structure, material, or acts within the claim itself to entirely perform the recited function.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action.
Similarly, an application may include one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier.
The following Claim limitations are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
Claims 1 and 20: power generation unit – read as “ a unit (generic placeholder) for power generation (function)…”
Claim 20: a regulatory device (generic placeholder) configured to generate a first control signal/second control signal/third control signal (function)…
Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof.
If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
For more information, see MPEP § 2173 et seq. and Supplementary Examination Guidelines for Determining Compliance With 35 U.S.C. 112 and for Treatment of Related Issues in Patent Applications, 76 FR 7162, 7167 (Feb. 9, 2011).
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP §§ 706.02(l)(1) - 706.02(l)(3) for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/process/file/efs/guidance/eTD-info-I.jsp.
Claims 1 – 20 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1 – 18 of US Patent No. 11927177. Although the claims at issue are not identical, they are not patentably distinct from each other as shown in the comparative table below:
Claim 1 of Instant Application
Claim 1 of US 11927177
A method comprising:
pumping, via an extraction well, heated water from an extraction depth of a hot sedimentary aquifer (HSA);
extracting, via a power generation unit, heat from the heated water to generate power and transform the heated water into cooled water; and
injecting, via an injection well, the cooled water at an injection depth of the HSA,
wherein:
the HSA is identified based on a permeability of the HSA satisfying a threshold permeability range,
the HSA comprises fresh or salt-water bearing sedentary rock,
a thickness of the HSA is equal to or less than about 100 meters, and
a first portion of the extraction well and a second portion of the injection well are disposed within the HSA.
A method comprising:
pumping, via an extraction well, heated water from an extraction depth of a hot sedimentary aquifer (HSA);
extracting, via a power generation unit, heat from the heated water to generate power and transform the heated water into cooled water; and
injecting, via an injection well offset from the extraction well by a first horizontal distance, the cooled water at an injection depth of the HSA,
wherein:
the HSA is identified based on a permeability of the HSA satisfying a threshold permeability range,
a thickness of the HSA is equal to or less than about 100 meters, and
a first portion of the extraction well and a second portion of the injection well are disposed within the HSA,
wherein the first portion of the extraction well comprises an extraction lateral extending horizontally and the second portion of the injection well comprises an injection lateral extending parallel to and offset from the extraction lateral by a horizontal distance, such that the injection lateral and the extraction lateral are configured to induce a convective recirculation cell within the HSA.
As seen above, the underlined portions of the US Patent are the same as the underlined portions of the instant claim. As such, the instant claim is a broader version of the US Patent claim and the US Patent claim anticipates the instant claim.
Although no comparative tables is shown for the remaining claims, they too are either directly anticipated by the US Patent or obvious over the US Patent in view of one of the references relied on below.
Claims 1 – 20 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1 – 27 of US Patent No. 11644220 in view of Willems (see 103 rejection below). Although the claims at issue are not identical, they are not patentably distinct from each other as shown in the comparative table below:
Claim 1 of Instant Application
Claim 1 of US 11644220
A method comprising:
pumping, via an extraction well, heated water from an extraction depth of a hot sedimentary aquifer (HSA);
extracting, via a power generation unit, heat from the heated water to generate power and transform the heated water into cooled water; and
injecting, via an injection well, the cooled water at an injection depth of the HSA,
wherein:
the HSA is identified based on a permeability of the HSA satisfying a threshold permeability range,
the HSA comprises fresh or salt-water bearing sedentary rock,
a thickness of the HSA is equal to or less than about 100 meters, and
a first portion of the extraction well and a second portion of the injection well are disposed within the HSA.
A method comprising:
pumping, via extraction wells, heated water from extraction depths of a hot sedimentary aquifer (HSA);
extracting, via a power generation unit, heat from the heated water to generate power and transform the heated water into cooled water; and
injecting, via injection wells, the cooled water at injection depths of the HSA,
wherein
the HSA is identified based on a permeability of the HSA satisfying a threshold permeability range,
and wherein the extraction wells and the injection wells form two or more well pairs.
The US Patent recites the extraction well and injection well both being disposed within the HSA by reciting “from extraction depths of a HSA” and “at injection depths of the HSA”. The US Patent does not explicitly recite a thickness of the HSA at 100 meters or less. Willems teaches a thickness of the HSA is equal to or less than about 100 meters (see Figure 4A showing a 50 m thick aquifer, see also caption of Figure 5 describing a base scenario with a “50 m thick aquifer”, and section 6, describing the lifetime of the aquifer “even if aquifer thickness is reduced to 50 m”). As per MPEP 2144.04, where the only difference between the prior art and the claims was a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device was not patentably distinct from the prior art device. Here, the size of the HSA has no bearing on the operation of the system or method.
Claims 1 – 20 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1 – 27 of US Patent No. 12135148 in view of Willems (see 103 rejection below). Although the claims at issue are not identical, they are not patentably distinct from each other as shown in the comparative table below:
Claim 1 of Instant Application
Claim 1 of US 12135148
A method comprising:
pumping, via an extraction well, heated water from an extraction depth of a hot sedimentary aquifer (HSA);
extracting, via a power generation unit, heat from the heated water to generate power and transform the heated water into cooled water; and
injecting, via an injection well, the cooled water at an injection depth of the HSA,
wherein:
the HSA is identified based on a permeability of the HSA satisfying a threshold permeability range,
the HSA comprises fresh or salt-water bearing sedentary rock,
a thickness of the HSA is equal to or less than about 100 meters, and
a first portion of the extraction well and a second portion of the injection well are disposed within the HSA.
A method comprising:
pumping, via an extraction lateral extending horizontally from an extraction well, heated water from extraction depths of a hot sedimentary aquifer (HSA);
extracting, via a power generation unit, heat from the heated water to generate power and transform the heated water into cooled water; and
injecting, via an injection lateral extending horizontally from an injection well, at least a portion of the cooled water at injection depths of the HSA,
wherein
the extraction well and the injection well form a well pair; and either: pumping, via a second extraction lateral extending horizontally from a second extraction well, heated water from extraction depths of the HSA for extracting heat via the power generation unit to generate power and transform the heated water into cooled water; or injecting, via a second injection lateral extending horizontally from a second injection well, a portion of the cooled water at injection depths of the HSA.
The US Patent recites the extraction well and injection well both being disposed within the HSA by reciting “from extraction depths of a HSA” and “at injection depths of the HSA”. The US Patent does not explicitly recite a thickness of the HSA at 100 meters or less or the HSA is identified based on a permeability. Willems teaches the HSA is identified based on a permeability of the HSA satisfying a threshold permeability range (see section 2 on Page 55, detailing the aquifer modelling in determining permeability based on a porosity-permeability relation obtained from petrophysical data, see also section 6 on how this permeability affected net present value and pumping losses). It would have been obvious to identify an HSA via a permeability range threshold in order to determine “value” of the HSA with regards to heat content. Willems further teaches a thickness of the HSA is equal to or less than about 100 meters (see Figure 4A showing a 50 m thick aquifer, see also caption of Figure 5 describing a base scenario with a “50 m thick aquifer”, and section 6, describing the lifetime of the aquifer “even if aquifer thickness is reduced to 50 m”). As per MPEP 2144.04, where the only difference between the prior art and the claims was a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device was not patentably distinct from the prior art device. Here, the size of the HSA has no bearing on the operation of the system or method.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102 of this title, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1 – 3, 10 – 12, 16, 17, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Willems et al. (hereafter “Willems” - C.J.L. Willems, H.M. Nick, T. Goense, D.F. Bruhn, “The impact of reduction of doublet well spacing on the Net Present Value and the life time of fluvial Hot Sedimentary Aquifer doublets”, Geothermics, Volume 68, 2017, Pages 54-66, ISSN 0375-6505, https://doi.org/10.1016/j.geothermics.2017.02.008, (https://www.sciencedirect.com/science/article/pii/S037565051630147X), in view of Leary (WO 2014148924).
With regards to Claim 1:
Willems discloses a method comprising:
pumping, via an extraction well (see wells in Figures 3, 4, at least one which is a production/extraction well as per section 3 on Page 56), heated water (hot water, see section 3 on Page 56) from an extraction depth of a hot sedimentary aquifer (HSA) (see abstract and section 1 introduction on Page 54, “hot sedimentary aquifers”);
extracting, via a power generation unit (see discussion of net electricity/energy production in sections 1, 3, and 6, requiring some form of power generation unit), heat from the heated water to generate power (section 1: “commercial electricity production”) and transform the heated water into cooled water (“cold water” see section 1); and
injecting, via an injection well (see wells in Figures 3, 4, at least one which is an injection well as per section 3 on Page 56), the cooled water at an injection depth of the HSA, wherein:
the HSA is identified based on a permeability of the HSA satisfying a threshold permeability range (see section 2 on Page 55, detailing the aquifer modelling in determining permeability based on a porosity-permeability relation obtained from petrophysical data, see also section 6 on how this permeability affected net present value and pumping losses),
the HSA comprises fresh or salt-water bearing sedentary rock (hot sedimentary aquifers, by definition, are sedimentary rock formations comprising pockets/layers of water. On Page 56, Willems teaches water density of 1050 kg/m^3, and uses a salinity dependent viscosity variable in one of the numerical approximations, indicating that the water is briny and comprises some salt content),
a thickness of the HSA is equal to or less than about 100 meters (see Figure 4A showing a 50 m thick aquifer, see also caption of Figure 5 describing a base scenario with a “50 m thick aquifer”, and section 6, describing the lifetime of the aquifer “even if aquifer thickness is reduced to 50 m”); and
and a first portion of the extraction well and a second portion of the injection well are disposed within the HSA (see Figures 3 and 4, see also caption of Figure 3, which states that the well target the aquifer itself).
For the sake of compact prosecution, Willems does not explicitly disclose a power generation unit in the vein of the present disclosure. Leary (Figure 1) teaches a power generation unit (power plant 160) receiving hot water (130) from a geothermal reservoir (200) and “configured to at least extract a natural (hot water) resource from the (geothermal) reservoir 200” (Page 6, Line 5) and reinjecting cooled water (110) back into the aquifer for reheating and to replenish the water extracted. Although Leary teaches an artificially created aquifer, from the perspective of the power plant, it is receiving hot water from some hot water source and using it to generate power. One of ordinary skill in the art would have found it obvious to employ a power generation system as shown in Leary to the hot sedimentary aquifer taught by Willems in order to extract energy from the hot water to produce electricity.
With regards to Claim 2:
The Willems modification of Claim 1 teaches the pumping the heated water comprises pumping, via the extraction well (Page 8, Line 25 of Leary: “The extraction of fluid such as the pumping rate may be controlled by the control system 170”), the heated water from the extraction depth of the HSA at an extraction rate that stimulates a flow field that provides a recharge of the extracted heat (Page 2, Line 24 of Leary: “Preferably the geothermal plant is arranged to extract hot fluid from the reservoir at a controlled rate and/ or temperature and/or pressure of fluid recovery, such as a controlled rate based on a measure of the effective wellbore region to maintain a temperature or a temperature range of the extracted fluid”).
With regards to Claim 3:
The Willems modification of Claim 1 teaches the permeability of the HSA is a bulk permeability of the HSA determined according to an analysis of geologic data associated with the HSA (see section 2.3 of Willems, permeability determined via core plugs porosity data and petrophysical data) to allow for sufficient pumping of the heated water to generate the power (see section 3 of Willems, where permeability data is used to determine pump energy requirements).
With regards to Claim 10:
Willems discloses a method comprising:
determining, according to a geothermal characteristic of a hot sedimentary aquifer (HSA) (see abstract and section 1 introduction on Page 54, “hot sedimentary aquifers”) below a surface location that satisfies a threshold associated with providing geothermal energy (see sections 1 and 3 describing selecting HSA that maximizes energy production), an extraction depth (see Figures 3, 4 and section 4 and 5 on Pages 57, 58, describing extraction depths and true vertical depths calculations) for an extraction well (see wells in Figures 3, 4, at least one which is a production/extraction well as per section 3 on Page 56) disposed to extract heated water from the HSA (hot water, see section 3 on Page 56) and an injection depth (see Figures 3, 4 and section 4 and 5 on Pages 57, 58) for an injection well (see wells in Figures 3, 4, at least one which is an injection well as per section 3 on Page 56) disposed to inject cooled water (“cold water” see section 1) into the HSA that is generated from a heat extraction process (see discussion of net electricity/energy production in sections 1, 3, and 6, requiring some form of power generation unit) associated with capturing geothermal energy;
configuring a geothermal system (see discussion of net electricity/energy production in sections 1, 3, and 6, requiring some form of power generation unit, see also section 1: “commercial electricity production” – note that “geothermal system” and “capturing geothermal energy” does not require power production) in association with the surface location to extract the heated water from the HSA at the extraction depth; and
configuring the geothermal system to inject cooled water into the HSA at the injection depth (“cold water” see section 1), wherein:
a thickness of the HSA is equal to or less than about 100 meters (see Figure 4A showing a 50 m thick aquifer, see also caption of Figure 5 describing a base scenario with a “50 m thick aquifer”, and section 6, describing the lifetime of the aquifer “even if aquifer thickness is reduced to 50 m”);
the HSA comprises fresh or salt-water bearing sedentary rock (hot sedimentary aquifers, by definition, are sedimentary rock formations comprising pockets/layers of water. On Page 56, Willems teaches water density of 1050 kg/m^3, and uses a salinity dependent viscosity variable in one of the numerical approximations, indicating that the water is briny and comprises some salt content), and
and a first portion of the extraction well and a second portion of the injection well are disposed within the HSA (see Figures 3 and 4, see also caption of Figure 3, which states that the well target the aquifer itself).
For the sake of compact prosecution, Willems does not explicitly disclose a power generation unit in the vein of the present disclosure. Leary (Figure 1) teaches a power generation unit geothermal system (power plant 160) receiving hot water (130) from a geothermal reservoir (200) and “configured to at least extract a natural (hot water) resource from the (geothermal) reservoir 200” (Page 6, Line 5) and reinjecting cooled water (110) back into the aquifer for reheating and to replenish the water extracted. Although Leary teaches an artificially created aquifer, from the perspective of the power plant, it is receiving hot water from some hot water source and using it to generate power. One of ordinary skill in the art would have found it obvious to employ a power generation system as shown in Leary to the hot sedimentary aquifer taught by Willems in order to extract energy from the hot water to produce electricity.
With regards to Claim 11:
The Willems modification of Claim 10 teaches configuring the geothermal system to pump, via the extraction well (Page 8, Line 25 of Leary: “The extraction of fluid such as the pumping rate may be controlled by the control system 170”), the heated water from the extraction depth of the HSA at an extraction rate that stimulates a flow field that provides a recharge of the extracted heat (Page 2, Line 24 of Leary: “Preferably the geothermal plant is arranged to extract hot fluid from the reservoir at a controlled rate and/ or temperature and/or pressure of fluid recovery, such as a controlled rate based on a measure of the effective wellbore region to maintain a temperature or a temperature range of the extracted fluid”).
With regards to Claim 12:
The Willems modification of Claim 10 teaches determining that the geothermal characteristic satisfies the threshold comprises: determining that an induced heat flow satisfies a heat flow threshold associated with providing the geothermal energy (see section 3 of Willems describing flow vectors and pumping/production energy, and Page 9, Line 4+ of Leary: “The invention therefore further relates to a method or system for extracting heat from a geothermal reservoir which requires the control of one or more operational properties of the fluid injection process to thereby control heat advection during the extraction process... The resulting injection/ extraction processes would then be operated in accordance with the customised injection properties to enhance the efficiency of heat extraction from the geothermal reservoir”, see also Page 2, Line 24 of Leary: “such as a controlled rate based on a measure of the effective wellbore region to maintain a temperature or a temperature range of the extracted fluid”).
With regards to Claim 16:
The Willems modification of Claim 10 teaches determining that the geothermal characteristic satisfies the threshold comprises determining that a temperature of the HSA at the extraction depth is at least some threshold (see Figure 5 of Willems showing production temperature being approximately 75 degrees C), but does not explicitly teach the temperature threshold is 120 degrees Celsius. However, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the threshold temperature to at least 120 degrees as applicant appears to have placed no criticality on the claimed range (see Paragraph 80 of the present application indicating the temperature “can” be within the claimed range) and since it has been held that “[i]n the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists”. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). In this case, the Willems modification is used to power a steam turbine, with steam being generated at temperatures of at least 100 degrees Celsius, which includes values that overlap with at least 120 degrees Celsius. Additional Willems seeks to maximize power production and the amount of recoverable heat (see sections 1 and 6.4 of Willems). Furthermore, the temperature can be seen as a result-effective variable, i.e. a variable which achieves a recognized result. A higher production/extraction temperature would result in additional power being available for the power plant to harness and one of ordinary skill in the art would have found it obvious to seek a HSA with a higher temperature at depth in order to maximize power production.
With regards to Claim 17:
The Willems modification of Claim 10 teaches determining a flow characteristic of the HSA (see sections 3 and 5 of Willems, paleo flow direction and Darcy flow velocity vector); determining, based on the extraction depth, the injection depth, and the flow characteristic, a water flow rate associated with extracting the heated water via the extraction well or injecting the cooled water via the injection well; and configuring the geothermal system to extract the heated water or inject the cooled water at the water flow rate (Page 2, Line 24 of Leary: “Preferably the geothermal plant is arranged to extract hot fluid from the reservoir at a controlled rate and/ or temperature and/or pressure of fluid recovery, such as a controlled rate based on a measure of the effective wellbore region to maintain a temperature or a temperature range of the extracted fluid”, Page 4, Line 1 of Leary: “Preferably the plant is configured to inject the cold fluid into the input wellbore while controlling one or more of the temperature, rate and/or pressure of the cold fluid during injection”, Page 4, Line 7 of Leary: “Preferably the plant is arranged to extract hot fluid from the reservoir at a controlled rate and/ or temperature and/ or pressure of fluid recovery based on the factor of the effective wellbore region to maintain a property or properties of the extracted fluid” – note that pressure of the fluid also varies by depth, and Leary teaches controlling pressure of fluid recovery).
With regards to Claim 20:
Willems discloses a geothermal system comprising:
a power generation unit (see discussion of net electricity/energy production in sections 1, 3, and 6, requiring some form of power generation unit, see also section 1: “commercial electricity production”);
a pump system (see section 3.1 discussing pump efficiency and energy losses, meaning some form of pump must be present);
a well system (see wells in Figures 3, 4) disposed within a hot sedimentary aquifer (HSA) (see abstract and section 1 introduction on Page 54, “hot sedimentary aquifers”), wherein the HSA comprises fresh or salt-water bearing sedentary rock (hot sedimentary aquifers, by definition, are sedimentary rock formations comprising pockets/layers of water. On Page 56, Willems teaches water density of 1050 kg/m^3, and uses a salinity dependent viscosity variable in one of the numerical approximations, indicating that the water is briny and comprises some salt content), wherein the well system comprises:
an extraction well (see wells in Figures 3, 4, at least one which is a production/extraction well as per section 3 on Page 56) that enables the pump system to provide heated water (hot water, see section 3 on Page 56) at an extraction depth of the HSA to the power generation unit (see section 3), and
an injection well (see wells in Figures 3, 4, at least one which is an injection well as per section 3 on Page 56) that enables the pump system to inject cooled water (“cold water” see section 1) from the power generation unit into the HSA at an injection depth (see section 3), wherein
a thickness of the HSA is equal to or less than about 100 meters (see Figure 4A showing a 50 m thick aquifer, see also caption of Figure 5 describing a base scenario with a “50 m thick aquifer”, and section 6, describing the lifetime of the aquifer “even if aquifer thickness is reduced to 50 m”), and
wherein a first portion of the extraction well and a second portion of the injection well are disposed within the HSA (see Figures 3 and 4, see also caption of Figure 3, which states that the well target the aquifer itself).
For the sake of compact prosecution, Willems does not explicitly disclose a power generation unit in the vein of the present disclosure. Leary (Figure 1) teaches a power generation unit geothermal system (power plant 160) receiving hot water (130) from a geothermal reservoir (200) and “configured to at least extract a natural (hot water) resource from the (geothermal) reservoir 200” (Page 6, Line 5) and reinjecting cooled water (110) back into the aquifer for reheating and to replenish the water extracted. Although Leary teaches an artificially created aquifer, from the perspective of the power plant, it is receiving hot water from some hot water source and using it to generate power. One of ordinary skill in the art would have found it obvious to employ a power generation system as shown in Leary to the hot sedimentary aquifer taught by Willems in order to extract energy from the hot water to produce electricity.
Willems also does not explicitly teach a regulatory device as recited. Leary teaches a regulatory device (control system 170) configured to (see Page 10, Lines 15+ for ability to generate signals): generate a first control signal configured to instruct the pump system to pump the heated water, from the extraction well, to the power generation unit (Page 6, Line 23: “The plant 160 may be arranged to extract a hot fluid from the reservoir at a controlled rate and/or temperature and/or pressure determined by the control system based on the factor relating to the effective wellbore region to maintain a parameter of the extracted fluid, such as the temperature or a temperature range of the extracted fluid or to substantially improve or maximise productivity of the plant 160”); generate a second control signal configured to instruct the power generation unit to extract thermal energy from the heated water and to transform the heated water into cooled water (Page 6, Line 23); and generate a third control signal configured to instruct the pump system to pump the cooled water from the power generation unit to the injection well (Page 4, Line 1: “Preferably the plant is configured to inject the cold fluid into the input wellbore while controlling one or more of the temperature, rate and/or pressure of the cold fluid during injection”). MPEP 2143A teaches it is obvious to combine prior art elements according to known methods in order to yield predictable results. In this case, one of ordinary skill in the art would have found it obvious to modify Willems to include a regulatory device in the mold of Leary in order to better control the power plant and the retrieval of hot water to substantially improve or maximise productivity of the plant.
Claims 4 – 7 and 13 – 15 are rejected under 35 U.S.C. 103 as being unpatentable over Willems et al. (hereafter “Willems” - C.J.L. Willems, H.M. Nick, T. Goense, D.F. Bruhn, “The impact of reduction of doublet well spacing on the Net Present Value and the life time of fluvial Hot Sedimentary Aquifer doublets”, Geothermics, Volume 68, 2017, Pages 54-66, ISSN 0375-6505, https://doi.org/10.1016/j.geothermics.2017.02.008, (https://www.sciencedirect.com/science/article/pii/S037565051630147X), in view of Leary (WO 2014148924), further in view of Wang et al. (hereafter “Wang” – CN 107461603) and Zhang et al. (hereafter “Zhang” – CN 105840146).
With regards to Claim 4:
The Willems modification of Claim 1 teaches the thickness of the HSA is equal to or less than about 50 meters (see Figure 4A of Willems showing a 50 m thick aquifer, see also caption of Figure 5 describing a base scenario with a “50 m thick aquifer”, and section 6, describing the lifetime of the aquifer “even if aquifer thickness is reduced to 50 m”), but does not explicitly teach a depth difference between the extraction depth and the injection depth is equal to or less than about the thickness of the HSA.
Wang (Figure 2) teaches a geothermal system including an injection and extraction well with laterals that connect to a heat exchanger (8) and a geothermal heat source (6). Wang also teaches vertical depth difference between the laterals that is approximately equal to or less than a rock reservoir (6) thickness, into which water is injected (as shown in Figure 2). In Wang, the injection and extraction wells are horizontally offset and the laterals of each well are vertically offset.
Zhang (Figures 1, 2) teaches a similar system including an extraction well (7) and an injection well (5) with a vertical depth difference between them that is approximately equal to or less than a rock reservoir (6) thickness into which water is injected. Zhang teaches that the extraction well is deeper than the injection well in order to “effectively utilizes the potential energy of different depth difference, greatly increases the flow capacity of the heat carrying medium” (see abstract). In other words, the direction of injection and gravity aid in directing the water downwards where it collects heat and is extracted at the extraction well. Given the teachings of Wang and Zhang, it would have been obvious to one of ordinary skill in the art to modify the system of Willems by arranging the injection and extraction wells spaced horizontally apart (as already shown in Figures 3, 4 of Willems) and adding laterals at different heights, as shown in Wang and Zhang, in order to utilize the existing potential energy and gravity force to reduce the pumping power required to direct the water to the extraction well from the injection well. Since Willems teaches the extraction depth and injection depth being located within the HSA itself (see Figures 3 and 4, see also caption of Figure 3, which states that the well target the aquifer itself), one of ordinary skill in the art would have also concluded that the depth difference between the extraction and injection depth is equal to or less than the thickness of the HSA.
With regards to Claim 5:
The Willems modification of Claim 4 teaches the first portion of the extraction well comprises an extraction lateral (see laterals of extraction wells in both Wang and Zhang); and the second portion of the injection well comprises an injection lateral (see laterals of extraction wells in both Wang and Zhang). The Willems modification further teaches a horizontal distance between the extraction lateral and the injection lateral is equal to or greater than about 300 meters (see Figures 3, 4 of Willems, where the distance L between the wells varies from 400 meters to 1000 meters and a closer spacing may result in an increase in the net present value of the HSA).
With regards to Claim 6:
The Willems modification of Claim 4 teaches the pumping the heated water (Page 8, Line 25 of Leary) comprises pumping the heated water via a production element and an extraction lateral of the extraction well (see laterals of extraction wells in both Wang and Zhang); the production element comprises an extraction pump (Page 8, Line 25 of Leary teaches controlling a pumping rate, so some form of pump must be present) and a vertical extraction component (see extraction bore 130 in Figure 1 of Leary) extending between the extraction depth and the power generation unit (as shown in Figure 1 of Leary); and the extraction lateral is mechanically coupled to the production element and comprises one or more lateral production branches that extend from the production element at the extraction depth (see laterals of extraction wells in both Wang and Zhang, which are connected to their respective vertical extraction components).
With regards to Claim 7:
The Willems modification of Claim 4 teaches the injecting the cooled water (Page 8, Line 25 of Leary) comprises injecting the cooler water via an injection element and an injection lateral of the injection well (see laterals of injection wells in both Wang and Zhang); the injection element comprises an injection pump (Page 8, Line 25 of Leary teaches controlling a pumping rate, so some form of pump must be present) and a vertical injection component (see injection bore 100 in Figure 1 of Leary) extending between the injection depth and the power generation unit (as shown in Figure 1 of Leary); and the injection lateral is mechanically coupled to the injection element and comprises one or more lateral production branches that extend from the injection element at the injection depth (see laterals of injection wells in both Wang and Zhang, which are connected to their respective vertical injection components).
With regards to Claim 13:
The Willems modification of Claim 10 does not explicitly teach a depth difference between the injection depth and the extraction depth is based on the geothermal characteristic.
Wang (Figure 2) teaches a geothermal system including an injection and extraction well with laterals that connect to a heat exchanger (8) and a geothermal heat source (6). In Wang, the injection and extraction wells are horizontally offset and the laterals of each well are vertically offset.
Zhang (Figures 1, 2) teaches a similar system including an extraction well (7) and an injection well (5) with a vertical depth difference between them that is approximately equal to or less than a rock reservoir (6) thickness into which water is injected. Zhang teaches that the extraction well is deeper than the injection well in order to “effectively utilizes the potential energy of different depth difference, greatly increases the flow capacity of the heat carrying medium” (see abstract). In other words, the depth difference is based at least partially on permeability and the possibility to utilize a potential energy/gravity to facilitate flow from the injection well to the extraction well. Given the teachings of Wang and Zhang, it would have been obvious to one of ordinary skill in the art to modify the system of Willems by arranging the injection and extraction wells spaced horizontally apart (as already shown in Figures 3, 4 of Willems) and adding laterals at different heights based on permeability / the ability to facilitate flow from the injection well to the extraction well, as shown in Wang and Zhang, in order to utilize the existing potential energy and gravity force to reduce the pumping power required to direct the water to the extraction well from the injection well.
With regards to Claim 14:
The Willems modification of Claim 13 teaches a depth difference between the extraction depth and the injection depth is equal to or less than about the thickness of the HSA (see Figures in both Wang and Zhang, depth difference between laterals is equal to or less than the thickness of their HSA).
With regards to Claim 15:
The Willems modification of Claim 13 teaches the first portion of the extraction well comprises an extraction lateral (see laterals of extraction wells in both Wang and Zhang); and the second portion of the injection well comprises an injection lateral (see laterals of extraction wells in both Wang and Zhang). The Willems modification does not explicitly teach a horizontal distance between the extraction lateral and the injection lateral is equal to or greater than about 300 meters (see Figures 3, 4 of Willems, where the distance L between the wells varies from 400 meters to 1000 meters and a closer spacing may result in an increase in the net present value of the HSA).
Claims 8, 9, 18, and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Willems et al. (hereafter “Willems” - C.J.L. Willems, H.M. Nick, T. Goense, D.F. Bruhn, “The impact of reduction of doublet well spacing on the Net Present Value and the life time of fluvial Hot Sedimentary Aquifer doublets”, Geothermics, Volume 68, 2017, Pages 54-66, ISSN 0375-6505, https://doi.org/10.1016/j.geothermics.2017.02.008, (https://www.sciencedirect.com/science/article/pii/S037565051630147X), in view of Leary (WO 2014148924), further in view of Lovelock (WO 2013/067570).
With regards to Claims 8 and 18:
The Willems modification of Claims 1 and 10 does not explicitly teach improving the permeability. Leary teaches the injecting the cooled water comprises: injecting, via the injection well, the cooled water to enhance the permeability of the HSA, wherein: before the injecting the cooled water, the permeability of the HSA does not satisfy the threshold permeability range; and after the injecting the cooled water, the permeability of the HSA satisfies the threshold permeability range (Page 6, Line 11 of Leary: “The region 131 preferably has an increased fracture connectivity and/or permeability through induced fracturing”, Page 6, Line 31 of Leary: “In particular, the system 300 is configured to induce fracturing thermally however, in alternative embodiments other fracturing techniques may be used instead”, Page 2, Line 10 of Leary: “increasing bulk permeability through the rock. The invention in effect increases the reservoir volume from which heat can be sustainably extracted in comparison with the reservoir volume that can be sustainably supplied by thermal conduction alone” – all of which suggest that the permeability is increased in order to meet heat transfer criteria, i.e. thresholds). Given these teachings, it would have been obvious to improve the permeability of the HSA of Willems in order to meet heat demands and from the power plant.
The Willems modification of Claims 1, 10, and 20 does not explicitly teach that the cooled water includes a supplemental agent. Lovelock teaches that “geothermal water often contains a high concentration of dissolved silica (Si0.sub.2) which, without treatment, may produce amorphous silica scale in plant equipment, surface pipelines or the injection well. Such scale can cause blockages or otherwise impair equipment operation and performance, leading to loss of production, which may impose significant costs” (Page 1, Line 21). Lovelock goes on to teach “one practice for dealing with such silica super-saturated water is to acidify the geothermal water to a pH of about 5 with a strong acid, such as sulphuric acid (H.sub.2S0.sub.4) or hydrochloric acid (HC1). Sulphuric acid has the advantages of low cost and being diprotic. The lowering of pH has the effect of delaying the polymerisation of the silica for sufficient time to allow the water to be piped to the injection well and be dispersed in the deep underground formation” (Page 1, Lines 27). MPEP 2143A teaches it is obvious to combine prior art elements according to known methods in order to yield predictable results. In this case, given the teachings of Lovelock, it would have been obvious to one of ordinary skill in the art to modify the system of Willems by adding a supplemental agent such as sulfuric or hydrochloric acid to the water in order to lower the pH to reduce scaling and blockages in the piping.
With regards to Claims 9 and 19:
The Willems modification of Claims 8 and 18 teaches the supplemental agent comprises a material selected from the group consisting of a muriatic acid, a hydrochloric acid, and a propellant-based agent (see Page 1, Line 27 of Lovelock, hydrochloric acid).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/Laert Dounis/
Primary Examiner, Art Unit 3746
Monday, January 12, 2026