Duncan Foley

Subject: Comments to Draft Specifications for Application of UNFC-2009 to Geothermal Energy Resources: from Duncan Foley
4 August 2016
Thank you for the opportunity to comment on the Draft Specifications for Application of UNFC-2009 to Geothermal Energy Resources. I have two general comments and several comments that may help to strengthen the examples.
My general comments:

• I suggest that two tables be added to the standards. One should be a flow unit conversion table, and the second an energy unit conversion table. Such tables would help an international audience put key data into familiar terms. Not all readers will be familiar with all units for flow or energy, so presenting conversions could help.
• For existing and any new graphics, I suggest that a red-green color scheme may not be helpful for colorblind readers. There are websites that can be used to test various graphics for colorblind visual compatibility.

My comments about the example cases:

• The criteria state that the people doing the evaluations should be identified. The evaluators are not identified in the examples. I think they should be.
• If case studies are going to be broadly applicable and followed, I suggest that the citation of references be greatly strengthened. References to published, gray, or in-house publications should be included for all key data and interpretations.
• While I like the idea of listing at the beginning of case studies the data date and the evaluation date, I note that in some cases the references cited don’t support the dates. For example, the Alto Peak case study lists a data date of December 2014 and an evaluation date of September 2015. The most recent reference, however, is 1997, which is 18 years before the evaluation. If nothing was written on this area in those 18 years, it should be clearly noted in the evaluation.
• There are places in the case study examples where phrases like “present technology” are used. The examples need to be clear about when the date of the so-called “present” is. In this case (Alto Peak) the term seems to refer to 1997, not 2015. A few things might have changed in those 18 years. The phrase “so far” (pg. 57) seems to refer to 2010 rather than the 2016 date of the evaluation. Which date is it really? Instructing evaluators to use exact dates rather than qualitative terms would be helpful.
• In many of the examples I had to dig for key data. How about requiring a table at the beginning that lists key parameters such as production temperature, flow rates, aquifer characteristics, depths of productive zones, etc.? Data in this table should be clearly identified as measured or anticipated. For anticipated data, the table could include a column describing the basis for the estimate. Such estimates then should be clearly supported by the evaluation or sources cited for the evaluation. This would help me, as a reader of an evaluation, have context ahead of my reading the details.
• Where abbreviations are used in examples they should be explained. Readers should not have to guess.
• Where formulas are used in examples, the units should be specified. Readers should not have to guess.
• I suggest that where examples use tables such as that on page 34 (Habanero), that both the incremental increases and total energy for each estimate be made clear. At a quick glance, the format of this table makes it look like the low estimate is the most energy, and the best and high estimates are actually relatively small amounts. I understand that the numbers are incremental, but adding the totals to each category would make it faster for the reader to understand what is being said.
• When terms are used that are important in local descriptions but might not be broadly understood, such as “risorgive” in the case study of Canavese, the terms should be explained in the text or a footnote. This term, for instance, does not show up in the US version of the glossary of geology. It does show up in a Google search, but primarily with references in Italian. Not all readers will speak local languages.
• When computer programs are used to support examples, they should be specifically named. Saying, as case study 10 does on page 79, “a commercial dynamic building simulator” is not specific enough. Maybe there is only one, but readers may not know this.

Comments from Duncan Foley to Draft Specifications for Application of UNFC-2009 to Geothermal Energy Resources.