Geothermal Heat Utilization Feasibility Study

Research output: ThesisMaster's Thesis

Authors

Abstract

A few reasons why OMV plans to diversify its existing energy portfolio are policy changes, zero-emissions targets, and public interest in environmentally friendly and low-carbon-emitting energy sources. Available know-how from decades of successful oil and gas production in the Vienna Basin facilitates OMV to achieve a competitive advantage. OMV's recent strategy changes and a planned investment of 5 billion euros into geothermal energy and alternative renewable energy sources accelerate the development and interest in heat utilization. Due to the lower geothermal gradient encountered in the Vienna Basin, heat recovery is the best way of utilizing the stored geothermal energy from the subsurface. Therefore, this study investigates the technical and economic feasibility of a hydrothermal doublet implemented into a Triassic reservoir in the Vienna Basin. The research aims to determine whether it can recover heat from the Reyersdorfer Dolomite commercially. Based on the literature review, environmental aspects of the application of geothermal energy, energy trends, potential, and state-of-the-art technologies are depicted. Analytical approaches are combined with geothermal reservoir simulation to investigate enthalpy production rates and temperature breakthroughs depending on altering several parameters to assess sensitivities. Technical considerations set the boundaries for economic estimations, which reveal NPV, IRR, and payout time for different production rate scenarios. Sensitivity analysis demonstrates parameters having the highest impact on the cash-based and non-cash-based approaches. The importance of appropriately selecting tubing diameters due to the encountered high friction pressure losses and resulting high power consumption is characterized. Heat transfer during production and injection strongly depends on the production rate and completion of components installed in the wellbore. Numerical reservoir simulation shows high initial enthalpy production rates facing a 16.5 % decline throughout 40 years of production. The assessment depicts the sensitivity of non-human controllable parameters and the importance of appropriately designing human-controllable parameters to counteract early temperature breakthroughs. This work demonstrates technical and economic feasibility. However, it reveals the complexity of geothermal heat recovery from the Triassic Dolomite and repeatedly emphasizes parameters that must be well understood and vital for a successful project.

Details

Translated title of the contributionGeothermische Wärmegewinnung Machbarkeitsstudie
Original languageEnglish
QualificationDipl.-Ing.
Awarding Institution
Supervisors/Advisors
  • Ott, Holger, Supervisor (internal)
  • Behrend, Jens, Supervisor (external), External person
Award date31 Mar 2023
Publication statusPublished - 2023