Complex sentence: The Klaipėda Geothermal Demonstration Plant in Klaipėda, Lithuania, constructed during the late 1990s and early 2000s, was the first geothermal heating plant in the Baltic Sea region.
Split into simpler sentences: The Klaipėda Geothermal Demonstration Plant is a geothermal heating plant in Klaipėda, Lithuania, constructed during the late 1990s and early 2000s. It was the first geothermal heating plant in the Baltic Sea region.