CARBFIX AND SULFIX IN GEOTHERMAL PRODUCTION, AND THE BLUE LAGOON IN ICELAND: GRINDAVÍK URBAN SETTLEMENT, AND VOLCANIC ACTIVITY

Abstract

This article analyses ways to maintain reservoir sustainability in the area surrounding the Blue Lagoon in Iceland, near the urban settlement of Grindavík on the Reykjanes Peninsula in Iceland. The Svartsengi geothermal power plant operations have pioneered the simultaneous production of electricity and hot water from a geothermal reservoir. The Blue Lagoon is a warm geothermal pool using brine from the power plant. This paper reports on the processes and procedures at the Blue Lagoon and the Svartsengi power station, aimed at increasing sustainability of the geothermal resource by injecting the geothermal brine back to ground, to ensure the geothermal resource sustainability in the area. This paper also discusses and explains in details the reduction of greenhouse gas emissions from geothermal plant operations in Iceland. When the steam from a geothermal reservoir emerges from the ground, it comes up with enough energy to drive turbine generators for electricity production. However, this involves releasing several greenhouse gases into the atmosphere, including hydrogen sulphide (H2S) and carbon dioxide (CO2). This research spotlights a geothermal power plant in Hellisheiði, Iceland, and the use of the CarbFix procedure of capturing and storing carbon dioxide, reducing CO2 emissions from the harnessing of geothermal resources for electricity. CarbFix is a carbon capture and storage (CCS) or carbon mineralization procedure aimed at binding CO2 to rock. This procedure has been used at Hellisheiði power plant for the past decade in Iceland. Scientists have also developed the SulFix procedure, to capture sulphate H2S in ground. These procedures, SulFix and CarbFix, reduce outlet of greenhouse gases by storing them in basalt rock – also referred to as mineral carbonation or carbon capture and storage. This involves dissolving the greenhouse gases in water, and re-injecting them back into the ground through boreholes, in Hellisheiði. This current research also shows the geology in these areas and reports on calculations that have found re-injection of greenhouse gasses to ground to be economically feasible. The paper covers several scenarios that have already been tested to determine the financial feasibility of capture and storage. These have involved calculating the estimated internal rate of return (IRR), the return on investment (ROI) and the present value (NPV). Economic calculations have been made, showing the CarbFix project to be a feasible option contributing to decreased greenhouse gas emissions.