| Title | Integrated Reservoir Management Strategies for Sustained Production at Krafla Geothermal Field, NE-Iceland |
|---|---|
| Authors | Anette K. Mortensen, Ásgerður K. Sigurðardóttir, Helgi Arnar Alfreðsson, Karl Emil Sveinsson, Kristján |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | The Krafla high-temperature geothermal field in northeast Iceland has been operational since 1978, currently with 60 MW of installed capacity. Declining output over time has resulted from reservoir pressure drawdown due to mass extraction and scaling-induced clogging in high-enthalpy production wells. To enhance sustainable utilization and mitigate production losses, a combination of five strategies has been implemented: 1.Intermittent Infield Reinjection to restore reservoir pressure. 2.Push-Pull Reinjection: Acidic wells undergo push-pull operations to improve fluid chemistry and output 3.Infield Micro-Reinjection: Focused reinjection near production zones has led to rapid output gains of targeted production wells. 4.Seasonal Well Resting: Selected wells are rested during summer, when hydropower output is high, allowing for short-term recovery in productivity. 5.Mechanical and Chemical Well Cleaning: Descaling has partially restored flow capacity in affected wells. These combined efforts have helped maintain full production capacity offsetting an estimated decline rate of 2 MW per year through eight years. Infield reinjection has emerged as the most impactful measure, but stimulation efforts have increased steam supply by up to 16%, delaying the need for drilling new makeup wells. Environmental benefits have also been significant. The reinjection of degassed brine has reduced the CO₂ concentration in the produced steam resulting in an annual reduction of approximately 3,000 tonnes of CO₂ emissions. These results underscore the potential of integrated production and reinjection strategies to enhance both sustainability and environmental stewardship in high-temperature geothermal fields. |