International Geothermal Association Lennershofstr. 140 44801 Bochum Germany White Paper Progress Update IGA Working Group for the Development of Geothermal Specifications for the UNFC-2009 Issue no. 2 2 November 2015 Prepared by: Gioia Falcone Reviewed by: the Working Group, the IGA R&R Committee and the Chair of the Task Force on Renewables Acronyms and Abbreviations (kept unaltered from the 1 st issue, with additions) AAPG American Association of Petroleum Geologists BVG German Geothermal Association CRIRSCO Committee for Mineral Reserves International Reporting Standards DOE US Department of Energy ECE United Nations Economic Commission for Europe ECOSOC United Nations Economic and Social Council EGRC Expert Group on Resource Classification EGS Enhanced/Engineered Geothermal System ESMAP Energy Sector Management Assistance Program of the World Bank GEA Geothermal Energy Association Generic Specifications Specifications for the application of the UNFC-2009 Geothermal Specifications Specifications for the application of the UNFC-2009 to Geothermal Energy Resources GSHP Ground source heat pump GtES Geothermal Energy Science IAEA International Atomic Energy Agency IEA-GIA International Energy Agency Geothermal Implementing Agreement IGA International Geothermal Association IGA R&R Committee IGA Resources and Reserves Committee IGA-SC IGA Service Company IRENA International Renewable Energy Agency MoU Memorandum of Understanding NEA Nuclear Energy Agency OECD Organisation of Economic Co-operation and Development PRMS Petroleum Resource Management System Red Book OECD NEA/IAEA Uranium Classification Renewables Specifications Specifications for the application of the UNFC-2009 to Renewable Energy Resources SPE Society of Petroleum Engineers SPEE Society of Petroleum Evaluation Engineers Task Force on Renewables Task Force on Application of UNFC-2009 to Renewable Energy UNECE United Nations Economic Commission for Europe UNFC United Nations Framework for Fossil Energy and Mineral Reserves and Resources UNFC-1997 United Nations Framework Classification for Reserves and Resources of Solid Fuels and Mineral Commodities UNFC-2004 UNFC for Fossil Energy and Mineral Resources 2004 UNFC-2009 United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009 WG IGA Working Group for the development of geothermal specifications for the UNFC-2009 WPC World Petroleum Council IGA Secretariat c/o Hochschule Bochum Lennershofstr. 140 44801 Bochum Gemany E-Mail: iga@hs-bochum.de Phone: +49 234 32 10712 Fax: +49 234 32 14809 IGA homepage: http://www.geothermal-energy.org
Introduction The scope of this 2 nd issue of the White Paper is to share with the public the progress being made by the WG since the release of the 1 st issue on 17 April 2015. The reader of this issue is referred to the 1 st issue for an introduction to the general principles and current status of the UNFC-2009, its applicability to renewable energy resources, and an explanation of the proposed structure to include geothermal energy via dedicated Geothermal Specifications. In what follows, an update on the WG s activities for the period 18 April 2015 to 30 October 2015 is provided, together with the first draft of the Geothermal Specifications (not yet in official UNECE format), inclusive of three initial application examples. The intended use of the Geothermal Specifications is in conjunction with the UNFC-2009 incorporating its Generic Specifications (as set out in ECE Energy Series No. 42, ECE/ENERGY/94) and the Renewables Specifications. The Renewables Specifications represent rules of application of UNFC-2009 to Renewable Energy Resources via the Generic Specifications, while the Geothermal Specifications represent rules of application of UNFC-2009 to Geothermal Resources, via the Renewables Specifications and the General Specifications (as opposed to stand-alone geothermal specifications). Progress on the application of UNFC-2009 to geothermal Since the release of the 1 st issue, the WG has met six more times by teleconference (on 11 May 2015, 3 June 2015, 9 July 2015, 20 August 2015, 13 October 2015 and 28 October 2015) and one more time in person, during a 2.5-day workshop in Reno, Nevada (23-25 September 2015), hosted by the GRC and co-sponsored by the U.S. DOE Geothermal Technologies Office and the World Bank-ESMAP. The WG kept extremely active, engaging in several technical discussions by email exchanges and via a dedicated Google Drive folder for its internal use. It also thoroughly reviewed the draft Renewables Specifications, offering valuable suggestions for improvement that are currently being evaluated by the Task Force on Renewables for implementation in a revised draft of the Renewables Specifications. The central concept in UNFC-2009 is the project. Resources are the quantities that are estimated to be extracted during the lifetime of the project, and are classified according to the status of the project. The project provides the basis for economic evaluation and decisionmaking. The identification and definition of the project remains the fundamental starting point also for the application of UNFC-2009 to geothermal resources. This led to several discussions within the WG on how to coherently capture situations where the evaluation is in the early stages, with a project being defined only in conceptual terms and yet with the need to define a reference point at which to report the estimated quantities. In the end it became clear that the choice of reference point may indeed vary from project to IGA Secretariat c/o Hochschule Bochum Lennershofstr. 140 44801 Bochum Gemany E-Mail: iga@hs-bochum.de Phone: +49 234 32 10712 Fax: +49 234 32 14809 IGA homepage: http://www.geothermal-energy.org
project, but its definition and disclosure (including any conversions applied downstream of it) aims precisely at avoiding misinterpretation of the reported quantities under UNFC-2009. Another focus point in the discussions of the WG was the reconciliation of different types and uses of geothermal resources within the same Geothermal Specifications. Clearly, the main challenge is posed by the inclusion of GSHPs, although a systematic approach to the definition of the reference point will again offer a path to resolution. Starting from the table of contents, which the Task Force on Renewables had already drafted (see 1 st White Paper), the WG started to build the Geothermal Specifications, avoiding as much as possible redundancy with the Renewables Specifications, given that the intended use of the Geothermal Specifications is not as stand-alone rules. Instead, the WG focused on the points where the geothermal context may need to be specifically addressed to clarify the application UNFC-2009 to geothermal resources, via the Renewables Specifications. During the activities of the WG, it became apparent that the best way to put the UNFC-2009 to the test with regards to its applicability to geothermal energy resources was to actually try t0 classify real and/or synthetic geothermal case studies. To support this process, in August 2015 the Task Force on Renewables provided the WG with examples of petroleum resources classification using the UNFC-2009. The WG then put considerable effort in selecting representative application examples for geothermal, with the goal of testing different possible situations (e.g. mature vs. immature project, country-wide vs. operator perspective, EGS systems vs. GSHPs, individual project classification vs. aggregation) and identifying any ambiguity in the interpretation of the UNFC-2009. Three selected application examples are presented in this first draft of the Geothermal Specifications, with the aim of producing around ten in the final draft to be submitted to the EGRC in April 2016. The application examples focus on classification of the estimates, rather than on their quantification, since this is in line with the spirit of the UNFC-2009 as a framework classification. Given that no reporting template is offered (or enforced) as part of the ECE Energy Series No. 42, ECE/ENERGY/94, the WG decided to develop one solely for the purpose of consistently presenting its application examples to the public, but with no intention of making it a rule. Via its Leader, the WG liaised with the Task Force on Renewables, the EGRC Technical Advisory Group and the EGRC E-axis and G-axis sub-groups. It also liaised with the IGA R&R committee via its Chair. Update on WG Process, milestones and schedule This 1 st issue of the White Paper was released at a side event at the World Geothermal Congress in Melbourne (presentation by Graeme Beardsmore) and at the 6 th session of the EGRC in Geneva (presentation by Gioia Falcone), both in April 2015. As of May 2015, IGA implemented a new structure of the IGA R&R Committee webpage to include the activities of the WG and represent a platform for public outreach. White Papers can be found there, along with other material: IGA Secretariat c/o Hochschule Bochum Lennershofstr. 140 44801 Bochum Gemany E-Mail: iga@hs-bochum.de Phone: +49 234 32 10712 Fax: +49 234 32 14809 IGA homepage: http://www.geothermal-energy.org
http://www.geothermalenergy.org/resources_and_reserves/working_groups/unfc_2009_working_group.html As of the date of this 2 nd issue of the White Paper, the tentative process schedule laid out in the 1 st issue remains unaltered, indicating that the progress of the WG is on track. The original schedule is reported here, with minor updates: WG to submit complete draft specifications to the IGA R&R Committee for review, and implement recommendations (~January 2016). [An incomplete draft is being shared with the public together with this 2nd issue] WG to submit draft specifications to the Task Force on Renewables and to the EGRC Technical Advisory Group (via the Task Force) for review, and implement recommendations (~February 2016). Following implementation of recommendations, IGA to submit a formal draft of the specifications to the UNECE at ~end February 2016, to allow time for translations, in line with UN protocol. Via the UNECE Secretariat, submit the draft specifications to the EGRC at its 7 th session in April 2016. After review by the EGRC, UNECE to post the draft specifications for a 3-month period of public comment (~June/July-September 2016) WG to formally address all comments and modify the draft as needed. Via the UNECE Secretariat, submit the modified draft specifications and the catalogue of comments and responses to the EGRC. If the modifications implemented following the public comment period are substantial, resubmit draft to the EGRC in April 2017. If the modifications are minor, the EGRC can endorse the Geothermal Specifications at an earlier date. The WG will continue to work according to this schedule, towards a complete set of draft Geothermal Specifications. References White Paper IGA Working Group for the Development of Geothermal Specifications for the UNFC-2009, Progress Update, Issue no. 1, 17 April 2015. IGA Secretariat c/o Hochschule Bochum Lennershofstr. 140 44801 Bochum Gemany E-Mail: iga@hs-bochum.de Phone: +49 234 32 10712 Fax: +49 234 32 14809 IGA homepage: http://www.geothermal-energy.org
UN Economic Commission for Europe Expert Group on Resource Classification Specifications for the application of the United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009 (UNFC-2009) to Geothermal Energy Resources Draft document prepared by the Geothermal Working Group Version 01 November 2015
Contents INTRODUCTION A B C D E F G H I Geothermal Resources and Products Corporate vs. National Resource Reporting Project and Reference Point Definition Project Lifetime/Limit Access to Source Access to Market Intermittent or Variable Extraction Projects with Multiple Resource Types E-axis Categories I.1 Distinction between and considerations for E1, E2 and E3 I.2 Considerations for use of Foreseeable Future I.3 Treatment of Policy Support I.4 Environmental and Social Considerations I.5 Definition and Use of E-axis Sub-Categories J F-axis Categories J.1 Distinction between and considerations for F1, F2 and F3 J.2 Treatment of Technology Developments J.3 Additional Quantities in place/in situ (Category F4) J.4 Definition and Use of F-axis Sub-Categories K G-axis Categories K.1 Considerations for Confidence Level (G1, G2 and G3) 2
K.2 Potential vs. Known Deposit (Category G4) L M Estimation & Classification Workflows Evaluator Qualifications ANNEXES E/F/G table Application examples 3
PREFACE At the 5 th session of the Expert Group on Resource Classification (EGRC) in April 2014, the Task Force on Application of the United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009 (UNFC-2009) incorporating Specifications for its Application (as set out in ECE Energy Series No. 42, ECE/ENERGY/94) to Renewable Energy was requested to provide at least one draft renewable commodity-specific specification for review at the 6 th session. To this end, the Task Force called upon the expertise of the International Geothermal Association (IGA) to provide specifications for the application of UNFC-2009 to geothermal energy resources using the full granularity of UNFC-2009. Through a Memorandum of Understanding (MoU) that was signed in September 2014, the UNECE and IGA agreed that their goals in the area of geothermal resources were mutually supportive. It was also agreed that the IGA represented the best platform and international umbrella to develop specifications and guidelines for the application of UNFC-2009 to geothermal energy, and to maintain evergreen the texts in a manner consistent with their proper application through regular and periodic review, under the aegis of the EGRC. Following the MoU, on 15 October 2014, the IGA issued a call for volunteers interested in joining a Working Group to draft the geothermal specifications for the UNFC-2009. A 12-member Working Group was appointed on 15 January 2015. Growing awareness and interest in renewable energy resources, including geothermal resources, has highlighted a need to normalize the way in which renewable energy potential is reported. The renewable energy industry has become a fully commercialized sector, in which several oil and gas majors have already started to play a significant role. These players have voiced a need for a common platform to assess and compare in a transparent way the potential of their renewable and non-renewable energy portfolios. A common assessment and comparison framework for renewable and nonrenewable energy resources is also needed by investors, regulators, governments and consumers as a foundation for a comprehensive overview of current and future energy sustainability scenarios at project, company, country, region or world level. With no globally agreed geothermal standards, guidelines or codes existing prior to the development of this document, it is hoped that the inclusion of geothermal energy within the UNFC-2009 will facilitate the improvement of global communication in the geothermal sector as part of the larger energy sector. 4
ACKNOWLEDGEMENTS The development of these specifications was undertaken by a Working Group of expert volunteers led by Gioia Falcone (Leader) with Miklos Antics, Roy Baria, Larry Bayrante, Paolo Conti, Malcolm Grant, Robert Hogarth, Egill Juliusson, Harmen F. Mijnlieff, Annamária Nádor, Greg Ussher and Kate Young. The efforts made by the Task Force on Renewables and by the IGA R&R committee (chaired by Graeme Beardsmore) in reviewing this document are greatly appreciated, as well as the roles of Graeme Beardsmore and Horst Rueter as observers of the activities of the Working Group. Further acknowledgements go to the EGRC Technical Advisory Group and to James Ross for their input in addressing technical issues that emerged during the activities of the Working Group. Face-to-face meetings of the Working Group by means of periodic workshops were made possible by the support of the Energy Sector Management Assistance Program of the World Bank (ESMAP), the US Department of Energy (DOE) and the Geothermal Research Council (GRC), with the logistical organization of the IGA Service Company. 5
INTRODUCTION The purpose of this document is to enable the application of the United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009 (UNFC-2009) incorporating Specifications for its Application (as set out in ECE Energy Series No. 42, ECE/ENERGY/94) to Geothermal Energy Resources. The intended use of this document is in conjunction with the UNFC-2009 incorporating Specifications for its Application (as set out in ECE Energy Series No. 42, ECE/ENERGY/94) and the Specifications for the Application of UNFC-2009 to Renewable Energy Resources (Renewables Specifications). The Renewables Specifications represent rules of application of UNFC-2009 to Renewable Energy Resources, while this document represents rules of application of UNFC-2009 to Geothermal Energy Resources, via the Renewables Specifications. Hence, this document is to be used only in conjunction with the two documents listed above, and not as a stand-alone document. Text that has been kept unaltered from the UNFC-2009 incorporating Specifications for its Application and/or the Renewables Specifications is indicated in this document in italics for clarity. A. Geothermal Resources In the geothermal context, the Renewable Energy Source is the internal energy contained in a body of rock, sediment and/or soil, including any contained fluids, that is available for extraction and conversion into Energy Products. This source is termed the Geothermal Source, and is equivalent to the terms deposit or accumulation used for solid minerals and fossil fuels. An Energy Product is directly linked to (or a direct replacement of) a fungible energy commodity and is saleable in an established market. Examples of Geothermal Energy Products are electricity and heat. Other non-energy products, such as inorganic materials or water for non-energy use, extracted from the Geothermal Source in the same extraction process do not qualify as Energy Products. However, where these non-energy products are sold, the revenue streams should be included in any economic evaluation. Geothermal Energy Resources are the cumulative quantities of Energy Products that will be extracted in the future from the Geothermal Source, measured or evaluated at the Reference Point. B. Corporate vs. National Resource Reporting The UNFC-2009 is geared toward classifying the resources associated with single projects. For reporting of corporate or national geothermal resources, the estimated quantities of the single projects may need to be aggregated. 6
The UNFC-2009, Part II, section IV and section VI.K provide guidance on the issues of national resource reporting and aggregation of estimated quantities. For national resource reporting, the aggregation of known projects from commercial and/or non-commercial and/or governmental organizations may not cover the total national geothermal resources. The creation of notional or hypothetical standard projects (with associated reference point) may allow an estimate and classification of all the nation s Geothermal Energy Resources, including those not yet linked to defined projects. These notional projects could be adequately classified as e.g. E3,F3.3,G4. C. Project and Reference Point Definition The resource classification process consists of defining a Project, or Projects, associated with a Geothermal Source, estimating the quantities of energy that can be recovered and delivered as Geothermal Energy Products by each Project, including any regenerative potential, and classifying the Geothermal Energy Resource based on the criteria defined by the E, F and G categories. The Project is the link between the Geothermal Source and quantities of Geothermal Energy Products and provides the basis for economic evaluation and decision-making. In the context of geothermal energy, the Project includes all the systems and equipment connecting the Geothermal Source to the Reference Point(s) where the final Geothermal Energy Products are sold, used, transferred or disposed of. The Project shall include all equipment and systems required for extraction and/or conversion of energy, including, for example, production and injection wells, ground or surface heat exchangers, connecting pipework, energy conversion systems, and any necessary ancillary equipment. In the early stages of evaluation, a Project might be defined only in conceptual terms, whereas more mature Projects will be defined in significant detail. (Definition of Reference Point in the geothermal context tba) D. Project Lifetime/Limit The estimated Geothermal Energy Resources for a Project are limited to quantities that will be produced during the Project Lifetime. The Project Lifetime will be the minimum of the economic limit, design life, contract period and entitlement period, as defined below. Because of its importance in estimating energy quantities, the Project Lifetime and its basis must be disclosed in association with any reported quantities. The economic limit is defined as the time at which the Project reaches a point beyond which the subsequent cumulative net operating cash flows from the Project would be negative. For a geothermal project, the economic limit may be the time when the expected extraction rate declines to make the Project uneconomic, or when it is uneconomic to invest in further extraction infrastructure such as additional wells. 7
E. Access to Source F. Access to Market The design life of a Project is the expected operating life of major physical infrastructure as defined during the technical and economic assessment of the Project. The replacement of significant project components will constitute a new Project and a new evaluation and estimation of Geothermal Energy Resources shall be performed. The contract period for a geothermal project is the term of all existing, or reasonably expected, sales contracts for the Energy Products. The contract period should not include contract extensions unless there is reasonable expectation of such extensions, based upon historical treatment of similar contracts. Entitlement defines the quantities that accrue to project participants. The entitlement period is the term of all licences and permits which provide rights to access the Geothermal Source, extract the Geothermal Energy Resources and deliver the Geothermal Energy Products into the market. The entitlement period should not include licence extensions unless there is reasonable expectation of obtaining such extensions, based upon historical treatment of similar licences issued by the issuing authority. The Geothermal Source may be expected to last much longer than the Project Lifetime, but any future extracted quantities beyond those estimated for the Project would be assessed and classified as subsequent or additional Projects. A geothermal Project gains access to an energy market through the application of processes and technologies, the development of needed infrastructure and policy settings that provide support and opportunity for financial reward through the subsequent sale of the Geothermal Energy Product(s) to target markets and stakeholders. Market access may or may not be supported by entitlements of the Geothermal Energy Product(s) to relevant tariff and non-tariff measures, incentives and certifications as set by the country s governing bodies. G. Intermittent or Variable Extraction When estimating Geothermal Energy Resources associated with a Project, future production scenarios are assumed (either explicitly or implicitly). Such scenarios describe expected yearly load hours and anticipated production rates, and should include operational/maintenance downtime. Depending on the market or the nature of the off-take of the Geothermal Energy Product (s), the Project may deliver at a constant base rate or with periodical variation between no (or minimum) production and maximum production, for example, the seasonal delivery of heat to a district heating system. 8
Assumed future production scenarios are generally based on estimated future annual energy production rates. These should include the seasonal swing in energy production and load hours. Taking into account the expected (seasonal) variability of future production within a given year, it is possible to report the cumulative energy produced in the subsequent reported years. Reduced or halted production due to a force majeure event (e.g. typhoon, landslide, flooding, earthquake, volcanic eruption) or unexpected operational issues are generally not included in the production forecast. If this is the case and production is halted for an extended period of time (> 1 year) then the classification of the Geothermal Energy Resources should be revised to reflect the likelihood of restarting production. H. Projects with Multiple Energy Products I. E-Axis Categories Where a Project produces more than one Geothermal Energy Product (e.g. heat and electricity), the Geothermal Energy Resources for each shall be classified separately, but included in a single report for the Project. The same information must be declared for each reported quantity, including the type of Geothermal Energy Product and its Reference Point. When a Project requires relevant input energy fluxes (e.g. electrical energy to drive heat pump compressors), these quantities should be estimated and reported along with the Geothermal Energy Resources. I.1 Distinction between and considerations for E1, E2 and E3 (To be completed) I.2 Considerations for use of Foreseeable Future (To be completed) I.3 Treatment of Policy Support When considering use of the subcategories E1.1 and E1.2, market based mechanisms such as a Feed in Tariff that are designed to recognise the value that offtakers or the state place on renewable energy (or geothermal energy specifically) and which are available to all such projects in the market, should not be considered a subsidy. I.4 Environmental and Social Considerations (To be completed) 9
I.5 Definitions and Use of E-axis Sub-Categories (To be completed) J. F-axis Categories J.1 Distinction between and considerations for F1, F2 and F3 A Geothermal Energy Resource associated with an Exploration Project (as defined in the UNFC-2009, Part II, Annex I) shall be classified as F3. The F3 category has three sub-categories (see UNFC-2009 Part II, section VI. R). The F3.3 sub-category relates to the earliest stages of exploration activities. These can include notional estimates of Geothermal Energy Resources for national resource reporting (see section B above). If the result of the first test well is dry, unsuccessful or inconclusive, the Geothermal Energy Resource estimate shall still be classified as F3, despite the presence of at least one exploration well. Note that, by definition, energy estimates associated with Exploration Projects are also classified as G4 under the G category (see section K). J.2 Treatment of Technology Developments (To be completed) J.3 Additional Quantities in place/ in situ (Category F4) In the context of finite resources, additional quantities in place make up the material balance between extracted quantities and total initial quantities inplace. Although a portion of these quantities may become recoverable in the future, as technological development occurs, some or all of these quantities may never be recovered. In the context of geothermal energy, however, the total initial quantity in place is poorly defined because: the physical limits of the Geothermal Source, particularly with depth, are poorly defined; recharge of the Geothermal Source replaces extracted energy at a rate that is also often poorly defined; and, the cut-off temperature below which heat extraction is no longer commercially viable is dependent upon the technology used in the Project. There may be situations where it is desirable to report additional quantities in place for a geothermal Project. At such times, by definition, the Reference Point for additional quantities in place is in situ. The assumed physical limits, the recharge rate and the cut-off temperature for the Geothermal Source shall be stated in any report showing additional quantities in place. 10
Additional quantities in place (F4) should not be reported unless classified using one of the following three F4 sub-categories: (a) F4.1: the technology necessary to recover some or all of the these quantities is currently under active development, following successful pilot studies on other deposits, but has yet to be demonstrated to be technically feasible for the style and nature of deposit in which that commodity or product type is located; (b) F4.2: the technology necessary to recover some or all of the these quantities is currently being researched, but no successful pilot studies have yet been completed; (c) F4.3: the technology necessary to recover some or all of these quantities is not currently under research or development. J.4 Definition and Use of F-axis sub-categories K. G-axis Categories K.1 Considerations for Confidence Level (G1, G2 and G3) The level of confidence for quantities is classified on the G-axis as G1, G2 and G3, defined as high, medium and low confidence, respectively. These category definitions are not specified more precisely because of the fundamental differences between the resource estimation methods commonly used in geothermal projects. There are three established approaches to determining the appropriate classification of Geothermal Energy Resource estimates within categories G1, G2 and G3. Two are based on an assessment of a range of uncertainty for the Geothermal Energy Resource estimate, and the third reflects different levels of confidence for different discrete portions of the Geothermal Source. The terms used within these specifications are as follows: The incremental approach, which is based on estimates for discrete portions of the Geothermal Source where each portion is assigned a level of confidence (high, medium or low) reflecting available geological knowledge; The scenario approach, which is based on three discrete scenarios that are designed to reflect the range of uncertainty in the possible outcomes (low, best and high estimates) of a Project acting upon the Geothermal Source as a whole; The probabilistic approach, where multiple possible scenarios are generated (e.g. by Monte Carlo analysis) from input distributions of parameter uncertainty associated with the Project acting upon the Geothermal Source as a whole. Three specific outcomes are then selected from the output distribution as representative of the range of uncertainty (e.g. P90, P50 and P10, where P90 means there is 90% probability of exceeding that quantity). 11
Where the scenario or probabilistic approaches are used, the low (or P90) estimate is classified as G1, the best (or P50) estimate is classified as G1+G2 and the high (or P10) estimate is classified as G1+G2+G3. Regardless of the analytical procedure used, Geothermal Energy Resource estimates may be prepared using the incremental, scenario or probabilistic approach. However, whichever approach is used, all three categories (G1, G2 and G3) should be reported to provide an indication of the range of uncertainty in the estimate. The above considerations also apply to G4.1/2/3 categories for Potential Geothermal Sources. K.2 Known versus Potential Geothermal Sources A Known Geothermal Source is one where one or more wells have established through testing, sampling and/or logging the existence of a significant quantity of potentially recoverable heat. In this context, significant implies that there is evidence of a sufficient quantity of recoverable heat to justify estimation of the Geothermal Resources demonstrated by the well(s) and for evaluating the potential for economic development. Recoverable implies that the thermal, permeability and fluid properties of the Geothermal Source have been shown to be suitable for recovering heat at rates which have a reasonable chance of being sufficient to support a commercial project. Estimated Geothermal Energy Resources associated with Known Geothermal Sources shall be classified and reported using the G categories, G1, G2 and G3. In the context of a ground sourced heat pump (GSHP) Project, the Geothermal Source shall be considered Known. A Potential Geothermal Source is one that has not yet been demonstrated to exist by direct evidence (e.g. drilling and - in some cases - well testing), but is assessed as potentially existing based primarily on indirect evidence (e.g. surface or airborne geophysical measurements, geochemical sampling of hot springs, etc.). Estimated Geothermal Energy Resources associated with Potential Geothermal Sources shall be classified and reported using the G category G4 or its sub-categories G4.1, G4.2 and G4.3. For Potential Geothermal Sources, the Probability of Discovery should be reported. This probability is the chance that further exploration, drilling and well testing will result in the confirmation of a Known Geothermal Source. Where heat in place has been identified by drilling, but the heat is not currently considered recoverable, such quantities may be classified and reported as G4 or its sub-categories, G4.1, G4.2 and G4.3, if considered appropriate for resource management purposes. A portion of these quantities may become recoverable resources in the future as commercial circumstances change or technological developments occur, but until recovery is demonstrated to be viable, these quantities shall be classified as Additional Quantities in Place through the use of the F4 category. 12
L. Estimation & Classification Workflows Geothermal Energy Resources are typically extracted from fluids and the mobile nature of those fluids generally precludes assigning recoverable quantities to discrete parts of a source. This is the same as for petroleum resources. Therefore, the scenario or probabilistic approach to resource estimation tends to be used far more often than the incremental approach. The incremental approach tends to be used primarily in mature hydrothermal environments. In these cases, typically, high confidence (G1) is assigned to portions of the Geothermal Source that have been drilled and to adjacent areas where there is high confidence in continuity of productive reservoir. Medium confidence (G2) and low confidence (G3) are assigned to progressively more remote areas. In the scenario approach, three separate analyses are prepared to bracket the uncertainty through sensitivity analysis (i.e., estimated values for three plausible sets of key geoscience and engineering input parameters). These scenarios are designed to represent the low, the best (qualitatively considered the most likely) and the high realizations of the original Geothermal Source and associated Geothermal Energy Resource quantities. The probabilistic approach is really an extension of the scenario approach, where a large number of discrete scenarios are generated from probability distributions of input parameters. The results define a probability distribution over the range of possible outcomes. The use of P90, P50 and P10 terminology is a way of reconciling the probabilistic approach with the scenario approach. In the context of the volumetric estimation approach, for example, a specific scenario means a single set of discrete parameter estimates (gross rock volume, average reservoir temperature, recovery factor etc.) that represent a physically realizable and realistic combination. The outcome is a single, specific estimate of recoverable energy. There should be no attempt to consider or report a range of uncertainty separately for energy estimates classified in categories G1, G2, or G3 because the objective is to estimate the range of uncertainty for the Project as a whole. M. Evaluator Qualifications Where a report detailing Geothermal Energy Resources is prepared for publication or submission to government authorities, the Geothermal Energy Resources shall be estimated by, or under the direction of, a Competent Person. Competent Persons must possess an appropriate level of expertise and relevant experience in the estimation of Geothermal Resources associated 13
with the type of Geothermal Source under evaluation. Some relevant national or financial reporting regulations may require a Competent Person to have specific qualifications and/or experience. As a minimum, a Competent Person shall have qualifications of, or equivalent to, a four-year tertiary course in geoscience, science or engineering and at least five years experience relevant to the type of Geothermal Source being evaluated. Any public report detailing Geothermal Energy Resources shall disclose the name of the Competent Person, state whether the Competent Person is an employee of the entity preparing the report, and, if not, name the Competent Person s employer. Estimation of Geothermal Energy Resources is very commonly a team effort, involving several technical disciplines. It is, however, recommended that only one Competent Person sign the Geothermal Energy Resource report, and that that person be responsible and accountable for the whole of the documentation. It is important in this situation that the Competent Person accepts overall responsibility for a Geothermal Energy Resource estimate and supporting documentation prepared in whole or in part by others, and is satisfied that the work of the other contributors is acceptable. 14
ANNEXE I E/F/G TABLE Category Definition Supporting Explanation (UNFC-2009, Part I, Annex I) Sub Categories Definition Additional Renewable Energy Context Additional Geothermal Energy Context E1 Extraction and sale has been confirmed to be economically viable Extraction and sale is economic on the basis of current market conditions and realistic assumptions of future market conditions. All necessary approvals/ contracts have been confirmed or there are reasonable expectations that all such approvals/contracts will be obtained within a reasonable timeframe. Economic viability is not affected by short-term adverse market conditions provided that longer-term forecasts remain positive. E1.1 E1.2 Extraction and sale is economic on the basis of current market conditions and realistic assumptions of future market conditions Extraction and sale is not economic on the basis of current market conditions and realistic assumptions of future market conditions, but is made viable through government subsidies and/or other considerations. Extraction is the process of converting a primary energy source (e.g. wind, solar power, biomass) into a marketable energy product (e.g. electricity, liquid transport fuel). In the geothermal context, heat is extracted from the Geothermal Source. In most projects, this heat is carried from the Geothermal Source to the surface via a fluid, typically brine or steam. At surface, the heat may be transferred to another working fluid through heat exchangers and may also be converted into electricity. This includes subsidies needed for present or future operation. If subsidies were used in the past (e.g. to drill a well), they are no longer relevant to the classification of the Geothermal Energy Resource. E2 Extraction and sale is expected to become economically viable in the foreseeable future. Extraction and sale has not yet been confirmed to be economic but, on the basis of realistic assumptions of future market conditions, there are reasonable prospects for economic extraction and sale in the foreseeable future. None --- --- ---
Extraction and sale is not expected to become economically viable in the foreseeable future or evaluation is at too early a stage to determine economic viability On the basis of realistic assumptions of future market conditions, it is currently considered that there are not reasonable prospects for economic extraction and sale in the foreseeable future; or, economic viability of extraction cannot yet be determined due to insufficient information (e.g. during the assessment phase). Also included are quantities that are forecast to be converted, but which will not be available for sale. E3.1 Quantities that are forecast to be extracted, but which will not be available for sale. --- For example, quantities produced and used internally (e.g. parasitic use, such as well pumping, power conversion loss, etc.) E3 E3.2 Economic viability of extraction cannot yet be determined due to insufficient information (e.g. during the exploration phase) For example, pre-successful well drilling exploration complete (if a drilled dry or unsuccessful, but further drilling is planned, this subcategory is still appropriate). Or, Where there is an active effort to obtain approval, the outcome is unknown or unclarified. E3.3 On the basis of realistic assumptions of future market conditions, it is currently considered that there are not reasonable prospects for economic extraction and sale in the foreseeable future. Uneconomic sites, for example sites far from transmission and/or demand Or Where there is an active effort to obtain approval, the likelihood of receiving approval is low. 16
Category Definition Supporting Explanation (UNFC-2009, Part I, Annex I) Sub Categories Definition Additional Renewable Energy Context Additional Geothermal Energy Context F1 Feasibility of extraction by a defined development project or mining operation has been confirmed. Extraction is currently taking place; or, implementation of the development project is underway; or, sufficiently detailed studies have been completed to demonstrate the feasibility of extraction by implementing a development project or mining operation. F1.1 Extraction is currently taking place. The term development Project is the renewable energy Project as described in Part II Category F4, i.e. in situ (in place) quantities, can be used to classify the currently nonextractable quantities at the geographical location of the defined Project due to, for example, site/area constraints, technology limitations and/or other constraints. Successful sustained operation of the Project up to Reference Point. For power projects, this typically includes wells and plant. For directuse projects, this typically includes the wells, piping and ancillary equipment up to the heat delivery point. For GSHP projects, this typically includes wells or ground heat exchangers, piping, heat pump unit(s) and ancillary equipment up to the user heat delivery point. Any adverse operational issues (e.g. chemistry, gas content, scaling, corrosion) can be managed. 17
F1.2 Capital funds have been committed and implementation of the development project or mining operation is underway. --- F1.3 Sufficiently detailed studies have been completed to demonstrate the feasibility of extraction by implementing a defined development project or mining operation. --- F2 Feasibility of extraction by a defined development project or mining operation is subject to further evaluation. Preliminary studies demonstrate the existence of a project in such form, quality and quantity that the feasibility of extraction by a defined (at least in broad terms) development Project or mining operation can be evaluated. Further data acquisition and/or studies may be required to confirm the feasibility of extraction. F2.1 Project activities are ongoing to justify development in the foreseeable future. --- For direct use and electricity projects, at least one well drilled indicating potential for production. For GSHP, studies are still ongoing (no drilling needed) F2.2 Project activities are on hold and/or where justification as a commercial development may be subject to significant delay. 18
Category Definition Supporting Explanation (UNFC-2009, Part I, Annex I) Sub Categories Definition Additional Renewable Energy Context Additional Geothermal Energy Context F3 Feasibility of extraction by a defined development project or mining operation cannot be evaluated due to limited technical data. Very preliminary studies (e.g. during the assessment phase), which may be based on a defined (at least in conceptual terms) development project or mining operation, indicate the need for further data acquisition in order to confirm the existence of a project in such form, quality and quantity that the feasibility of production can be evaluated. F3.1 (*) Where site-specific geological studies and exploration activities have identified the potential for an individual deposit with sufficient confidence to warrant drilling or testing that is designed to confirm the existence of that deposit in such form, quality and quantity that the feasibility of extraction can be evaluated; --- Pre-successful well drilling exploration complete (if a drilled well is dry or unsuccessful, but further drilling is planned, this subcategory is still appropriate). F3.2 (*) Where local geological studies and exploration activities indicate the potential for one or more deposits in a specific part of a geological province, but requires more data acquisition and/or evaluation in order to have sufficient confidence to warrant drilling or testing that is designed to confirm the existence of a deposit in such form, quality and quantity that the feasibility of extraction can be evaluated; --- Pre-drilling exploration in progress 19
F3.3 (*) At the earliest stage of exploration activities, where favourable conditions for the potential discovery of deposits in a geological province may be inferred from regional geological studies. --- Regional geothermal potential studies F4 No developmen t project or mining operation has been identified. In situ (in-place) quantities that will not be produced by any current development project or mining operation. F4.1 F4.2 The technology necessary to recover some or all of the these quantities is currently under active development, following successful pilot studies on other deposits, but has yet to be demonstrated to be technically feasible for the style and nature of deposit in which that commodity or product type is located; The technology necessary to recover some or all of the these quantities is currently being researched, but no successful pilot studies have yet been completed; --- --- --- --- F4.3 The technology necessary to recover some or all of these quantities is not currently under research or development. --- --- (*) For quantities associated with Exploration Projects. 20
Category Definition Supporting Explanation (UNFC-2009, Part I, Annex I) Sub Categories Definition Additional Renewable Energy Context Additional Geothermal Energy Context G1 Quantities associated with a known deposit that can be estimated with a high level of confidence. For in situ (in-place) quantities, and for recoverable estimates of fossil energy and mineral resources that are extracted as solids, quantities are typically categorised discretely, where each discrete estimate reflects the level of geological knowledge and confidence associated with a specific part of the deposit. The estimates are categorised as G1, G2 and/or G3 as appropriate. For recoverable estimates of fossil energy and mineral resources that are extracted as fluids, their mobile nature generally precludes assigning recoverable quantities to discrete parts of an accumulation. Recoverable quantities should be evaluated on the basis of the impact of the development scheme on the accumulation as a whole and are usually categorised on the basis of three scenarios or outcomes that are equivalent to G1, G1+G2 and G1+G2+G3. --- Highconfidence estimate (low estimate) The G-axis represents the level of confidence in estimates of the quantities of extractable, or potentially extractable, Renewable Energy Resources associated with the Project. These could be considered as reflecting uncertainties impacting the Project and typically would cover areas such as meteorology, climatology, topography and other branches of geography, ecology, and geology (for Geothermal Projects). Typically the various uncertainties will combine to provide a full range of possible outcomes, comparable to the extraction of fluids in the petroleum sector. In such cases, categorization should reflect three scenarios or outcomes that are equivalent to G1, G1+G2 and G1+G2+G3. --- G2 Quantities associated with a known deposit that can be estimated with a moderate level of confidence. --- Moderateconfidence estimate (best estimate) incremental to G1 --- 21
G3 Quantities associated with a known deposit that can be estimated with a low level of confidence. --- Lowconfidence estimate (high estimate) incremental to G2 --- 22
Category Definition Supporting Explanation (UNFC-2009, Part I, Annex I) Sub Categories Definition Additional Renewable Energy Context Additional Geothermal Energy Context G4 Estimated quantities associated with a potential deposit, based primarily on indirect evidence. Quantities that are estimated during the exploration phase are subject to a substantial range of uncertainty as well as a major risk that no development project or mining operation may subsequently be implemented to extract the estimated quantities. Where a single estimate is provided, it should be the expected outcome but, where possible, a full range of uncertainty in the size of the potential deposit should be documented (e.g. in the form of a probability distribution). In addition, it is recommended that the chance (probability) that the potential deposit will become a deposit of any commercial significance is also documented. G4.1 G4.2 High-confidence estimate (low estimate Moderateconfidence estimate (best estimate) incremental to G4.1 Category G4 (Exploration Projects) is equally applicable to Renewable Energy quantities, based on the definition Estimated quantities associated with a potential Project, based primarily on indirect evidence. G4 could be used to classify Renewable Energy from resource mapping studies (indirect evidence) that generally require more detailed and further (onsite) data acquisitions and evaluation to confirm the (economic) potential of the Renewable Energy Source (the Deposit ) at location. For example, delineation by surface surveys; evidence, of rock-water interactions, spring analysis, temperature gradient, regional heat-flow maps, etc. For GSHP projects, G4 does not apply. G4.3 Low-confidence estimate (high estimate) incremental to G4.2) 23