Shallow geothermal energy system in fractured basalt: A case study from Kollafjørður, Faroe Islands, NE-Atlantic Ocean

Abstract

A shallow (≈200 m) geothermal energy system is examined in the Faroe Islands, a 60-million-year-old volcanic archipelago in the Northeast Atlantic. The geothermal water has a heating capacity of approximately 150 individual households and consists of meteoric water approximately 3 years old. Water temperatures as high as 27 °C in artesian wells are explained by a topography-driven vertical convection. The water flows into the boreholes from the north-northwest through fractures and flow tops and bases in the basalt exposed in surrounding high terrains. Of six influx zones, three are water carrying fractures that strike N–S and dip E.