Death by Injection - Reopening the Klaipeda Geothermal Cold Case

Abstract

In 2017 the Klaipeda geothermal plant in Lithuania was shut-down and the operating company declared bankruptcy. Between 2001 and 2017, the low enthalpy project was supplying heat to a local heat loop. That project was part of the Lithuania energy transition plan and as such had received substantial public funding. From the beginning, the injector wells were unable to accommodate the desired rate, while producers had excellent delivery. A string of studies identified a string of damaging mechanisms and suggested as many remedial actions. These remedial actions included: drilling a second injector, acidization, side-tracking and radial jet drilling (RDJ). These actions had only disappointing and at best short-lived impacts on the issue. We conducted a post-mortem review, admittedly limited to the amount of data publicly available in the related literature. Nonetheless, after a thorough analysis of observations, petrophysical and production logs, injection and production data, we can explain the most prominent damage mechanism plaguing the Klaipeda injector wells. Along, we identify the major flaws pertaining to the injector well design. Based on these conclusions, we propose remedial actions to revive the Klaipeda geothermal project, hoping that the present work will also serve as a basis for best practices to all who want to drill and complete efficient injector wells in clastic reservoir rock.