GPOS Evaluation for Geothermal Projects in the Netherlands

Summary Every subsurface project has the risk of failure or disappointment if the predictions made by the subsurface evaluation team are incorrect. In some cases the reality is so much different from the expected that no production is possible or allowed. This is well known for hydrocarbon wells, but also in geothermal projects prediction errors are possible that could result in a total write off of the well or the project. To cater for these risks a fit-for-purpose GPOs evaluation scheme for geothermal projects has been developed within EBN. A consistent GPOS evaluation will help EBN to determine the correct usage of funds in its mission to explore for and accelerate the use of geothermal energy in the Netherlands. Five subsurface aspects are seen as the main parameters determining the technical success of a geothermal project in the Netherlands: Aquifer, Permeability, Fluid Compatibility, Temperature and Connectivity. These five parameters constituting GPOS are estimated by different techniques. The main data and evaluation techniques, both for the pre-drilling estimate of GPOS and the post-drilling evaluation of the project are discussed.