Continuous H2S Monitoring Solution Protects People and the Environment in Reykjavik

Geothermal energy is generated by tapping into heat stored beneath the Earth’s surface and is particularly prevalent in areas with high volcanic activity or underground sulfur deposits. Although it is a relatively clean and renewable energy source, H₂S can be released throughout the production process, creating concerns due to its potential toxicity and strong, unpleasant odor often compared to rotten eggs.

According to the Environment Agency of Iceland, geothermal energy production in the Reykjavik area continues to increase. With the smell of H₂S periodically noticeable throughout the area, the Department of Environment for Reykjavik City has measured H₂S concentrations since 2006, with levels expected to remain below 50 micrograms per cubic meter.

Managing H₂S in Geothermal Energy Production

Developed on one of Iceland’s largest high-temperature geothermal fields, this extensive site is one of the world’s foremost geothermal power plants, producing and supplying both electricity and hot water for district heating networks serving Reykjavik.

District heating uses a centralized heat source, in this case geothermal fields, to distribute hot water through a network of insulated pipes to homes and commercial buildings. As geothermal fluids are used throughout the energy and hot water production process, monitoring H₂S provides plant operators with important information about sulfide levels within the system.

To support regulatory compliance and better manage H₂S levels, managers at the geothermal power plant turned to Badger Meter for a BlueEdge™ solution capable of continuously monitoring sulfide within the district heating water.

Monitoring H₂S in District Heating Water

The Q46S/81 Dissolved Sulfide AutoChem Monitor was selected to provide continuous measurement of sulfide within the district heating system.

Falling within the measurement and control element of the BlueEdge portfolio, the Q46S/81 uses a gas-phase measurement method to continuously measure sulfide without contact between the sensor and water sample. This approach provides reliable measurement while limiting sensor exposure to the sample.

The system is compatible with communication protocols including Modbus-RTU, Profibus-DP and Ethernet/IP, allowing measurement data to be incorporated into broader plant monitoring and control systems.

Combined with connectivity and communication capabilities, continuous sulfide measurement provides plant operators with near real-time data on changing conditions and greater visibility into H₂S levels throughout the district heating system.

Supporting Safer Geothermal Operations

Continuous monitoring of H₂S within the district heating water gives plant operators greater visibility into sulfide conditions and helps identify changes that may require attention.

Access to reliable H₂S data supports regulatory compliance, worker and community safety and more informed management of geothermal operations. It also helps the facility manage potential environmental impacts while continuing to provide electricity and hot water to the Reykjavik area.