| Title | Development of superhot resources at Hengill |
|---|---|
| Authors | Sigurdur H. Markusson, Arna Pálsdóttir, Pálmar Sigurdsson |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | The Hengill volcanic system is one of Iceland’s most productive geothermal sites, powering both the Hellisheiði and Nesjavellir plants with combined heat and power production accounting for 43.9% of Iceland's primary energy extraction from geothermal. With an estimated coverage of 110 km², and most of the current extraction occurring above 2,000 meters, the next phase of development focuses on accessing deeper, superhot zones where temperatures exceed 400°C, unlocking vast volumes of stored thermal energy. Reykjavik Energy is advancing a multi-staged R&D plan exploring three different approaches: 1.Deep reinjection into superhot formations below the current production 2.Direct production of superhot fluids from deep wells 3.An EGS-style coupled deep production-injection with enhanced permeability To successfully develop new solutions for these extreme conditions, an integrated scientific and engineering approach is required. This includes improved equipment design and material use for key components and advancing our understanding of fluid behavior and reservoir characteristics at depth. Essential to this plan is a strong international academic and industry cooperation, such as through the IDDP project and multiple EU grant programs. The next IDDP well, IDDP-3, is scheduled in 2028 in the Hengill area. Meanwhile, pilot testing of new technologies and methods will be conducted. Testing will utilize shallow superhot zones (~2 km depth) intersected previously in four wells across three different subregions, offering a lower-risk platform before proceeding to 3-5 km custom-designed wells. |