Hellisheiði Power Station

Hellisheiði Power Station. Located on the Hengill volcanic area in southwestern Iceland, it is one of the world's largest geothermal power stations. Owned and operated by Orkuveita Reykjavíkur, the facility provides electricity to the Capital Region and thermal energy for district heating in Reykjavík. Its development represents a major milestone in Iceland's transition to renewable energy.

History

Planning for the facility began in the early 2000s to meet growing energy demand in the Reykjavík area. Construction commenced in 2005, with the first phase inaugurated in 2006. Subsequent expansions in 2007 and 2011, involving additional turbines from Fuji Electric, increased its capacity significantly. The project was developed by Orkuveita Reykjavíkur, the main utility for the Capital Region, drawing on decades of experience from older plants like the Nesjavellir Geothermal Power Station. The site was chosen for its proximity to the high-temperature Hengill geothermal field, which had been studied extensively by the Iceland GeoSurvey.

Technical specifications

The station has an installed capacity of 303 MWe of electrical power and 133 MWt of thermal energy. It utilizes a combination of flash steam and binary cycle technology to maximize efficiency from the geothermal fluid. The plant operates with multiple high-pressure turbines supplied by Fuji Electric, extracting energy from steam separated from brine extracted from over 30 production wells. The residual hot water is then used for the district heating network before being reinjected, while non-condensable gases like hydrogen sulfide are processed. The control systems are integrated with the wider grid managed by Landsnet.

Environmental impact

While generating clean energy, the operation has notable environmental effects. The reinjection of spent geothermal fluid is designed to minimize ground subsidence and sustain reservoir pressure. A primary challenge is the emission of non-condensable gases, including hydrogen sulfide and carbon dioxide; the station employs a pilot project, CarbFix, in collaboration with the University of Iceland and Columbia University, to inject CO₂ into basalt for mineralization. The project's footprint on the Hellisheiði plateau has altered local landscapes, though efforts are made to protect surrounding areas like the Þingvellir National Park. Monitoring is conducted by the Environment Agency of Iceland.

Economic significance

The power station is a cornerstone of the local economy, providing stable, low-cost electricity for energy-intensive industries such as the Alcoa Fjarðaál smelter in Reykjanesbær. It secures the energy supply for the Capital Region, supporting households and businesses. The project has fostered expertise exported globally by Icelandic firms like Reykjavík Geothermal and Mannvit. Revenue from power sales funds further renewable energy research and municipal services for Reykjavík. Its operation reduces Iceland's reliance on imported fossil fuels, improving national energy security.

Future developments

Ongoing research focuses on enhancing efficiency and mitigating emissions. The CarbFix project aims to be scaled up for permanent carbon storage. There are plans to increase the utilization of waste heat for industrial applications and greenhouses. Exploration of deeper, hotter resources within the Hengill area is underway to potentially boost capacity. The station is also a testbed for international projects, including collaborations with the European Union and the International Energy Agency, exploring the future of geothermal energy and carbon capture and storage technology.

Category:Geothermal power stations in Iceland Category:Buildings and structures in the Capital Region (Iceland) Category:2006 establishments in Iceland