Chapter 8 - Life cycle assessment of geothermal power technologies

Abstract

This chapter starts with an overview of available technologies for generating electricity from geothermal resources. These technologies are introduced in the order of the quality of the geothermal resource that they harness, starting from steam-dominated reservoirs. The overview covers four mature technologies: dry-steam, single- and multistage flash plants, and binary plants, as well as enhanced geothermal systems, an emerging technology. The core of the chapter provides a compendium of methodological recommendations for applying life cycle assessment (LCA) to the geothermal power sector. The discussion intends to cover each phase of the LCA methodology, that is, goal and scope of definition, life cycle inventory (LCI) analysis, life cycle impact assessment, and life cycle interpretation. Since the LCI analysis is arguably the most challenging phase, the discussion is extensive. It includes key aspects and parameters that require consideration for modeling the life cycle of a geothermal power plant and the main activities that makeup such a life cycle. The chapter concludes with a summary of results from a few case studies.