First Efforts to Address Challenges in Klaipeda Geothermal Site (WP4)
At the western coast of the Baltic state, warm salty water is pumped from rocks 1000 m beneath the city of Klaipeda. Sigitas Petrauskas, Robertas Valickas and Antanas Petraitis from Geoterma, the local operator, are especially proud of the recently received certificate, which approves that the water is clean and even eligible for spa purposes.
Although the team is happy about the strong discharge from the reservoir, at the same time they worry about low recharge into the underground: Running geothermal fluids in a subsurface loop is a main requirement for sustainable use of geothermal energy. Therefore, produced fluid has to be injected back into the reservoir formation. However, geothermal fields often face problems during injection, as the Klaipeda geothermal demonstration site does. Several treatments on site did not bring expected increase of injection rates. Reasons can be manifold and will be investigated with interdisciplinary methods within DESTRESS.
In March and July 2016 geochemists, reservoir engineers and rock mechanic experts from GFZ Potsdam visited the site to sample fluids, filter residual and core pieces for analysis in the laboratory. Discussions between local and visiting experts revealed interesting details, which will presumably help to solve the challenges at Klaipeda Geothermal Power Plant.