Trying to work with the current myriads of non-standardised terms, definitions, and well design types for geothermal projects is challenging. Interest in the sector is growing rapidly, but its technical complexity and lack of a standard nomenclature are inhibiting the clarity of debate worldwide. The challenge of the IADC Geothermal Committee is to bring simplicity and standardisation to the entire geothermal ‘ecosystem’.
The motivation of this committee is to create universally acceptable guidelines for the benefit of the geothermal community, operators, investors, and regulators. We talked to Kevin Gray and Daria Ivakhnenko from Black Reiver Geothermal Consulting, members of the IADC Geothermal committee steering group who were the instigators of this classification initiative.
How would regulators and investors benefit from the Classification?
“Regulators will be able to use the Classification to more easily identify the risks that may exist within geothermal projects. The Classification part of our work, in conjunction with the evolving guidelines, aims to help bring clarity and, hopefully, a more widespread harmonisation of the current globally diverse permitting processes.”
“For any well categorised within the framework the IADC Geothermal Committee is developing, it will be easier for the authorities to identify the required regulatory input. Thus, it will simplify the process and shorten the time required to receive approvals. It will also help identify wells that may benefit from a regulatory ‘light touch’ approach within, for example, the environmental aspects of the permitting system.”
“Investors have become quite excited about this development too, as it gives them a shortcut to the first stage due diligence as it more clearly defines the specifics and complexity of a geothermal project. It will help them evaluate the risks associated with a specific project, which goes a long way in making an investment decision. In addition to the classification itself, the committee have been developing a risk assessment tool that assigns an overall project risk to any classified well.”
What was the most difficult classification issue?
“Without a doubt, that was the Well Design and Construction categories. Too many entrenched opinions and existing temperature-based geothermal well classifications often lead to heated discussions as soon as any temperature threshold is raised. This Classification is based on well construction, the practicality of ‘putting a hole in the ground’, hence we decided to move away from existing academic disputes and concentrate on well equipment operating temperatures.”
“The result was to define wells that require no active cooling measures and those that need additional cooling strategies for the downhole tools or surface drilling equipment.”
“In the end, the committee chose the most straightforward and pragmatic approach of using the existing API and ISO drilling equipment standard operating temperatures. Beyond these thresholds, mitigating measures such as insulated tubulars or cooling techniques are required.”
