Adapting Unconventional Oil and Gas CompletionTechnology: a Key Factor in Reducing Risks Associated to EGS projects

2nd International Geothermal Conference, GEOHEAT2018

Meier, P.M.^1 ; Guinot, F.^1

Geo-Energie Suisse AG, Reitergasse 11, Zürich

CH 8004, Switzerland^1

关键词: Completion technology;    Energy depletion;    Energy productions;    Geothermal fluids;    Geothermal projects;    Multistage system;    Net present value;    Unconventional oil and gas;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/249/1/012024/pdf
DOI  :  10.1088/1755-1315/249/1/012024

来源: IOP

【 摘 要 】

When two wells are drilled into a petrothermal formationnormally the transmissivity is so low that no economical project is possible. Therefore there is a lot at stake, for geothermal developers, in understanding EGS reservoir creation, and in developing technologies that achieve the EGS designed size and transmissivity.The EGS becomes an economical proposition only when enough rock surface can be contacted by the geothermal fluid, and when the flow path runs smoothly through a sufficient rock volume. Then, energy depletion is minimized and the project can run over a long period, compatible with a positive net present value (NPV). To that end, the well design and its completion system have to be engineered to maximize the chances of properly creating and operating the EGS. In this paper, lessons learnt from the Basel geothermal project are reviewed and analyzed to propose a multi-stage system as a mean of reducing some of the risks associated to geothermal wells (not enough energy production and seismic risks). Current oil and gas (namely "unconventional") completion technologies related to multi-stage stimulation have been evaluated in the scope of a deep geothermal EGS project.