Risk Governance of Deep Geothermal and Hydro Energy (RISK-GOV: DGE & Hydro)

The exploitation of underground energy resources as well as the use and expansion of hydropower, are, like all energy technologies, not completely risk free. The primary risks identified in the domain of deep geothermal are induced seismicity and other risks (e.g. borehole blowout, environmental risks). The hazard factors for hydropower are those classically affecting large arch or gravity dams, aggravated by the pronounced topography of the Alpine region and by the rapidly changing climatic conditions in the Alps. Moving towards a safe and more resilient energy sector requires tools for hazard and risk assessment, particularly in the low probability-high consequence (LP-HC) event settings. This project aims to develop a risk governance framework by integrating risk assessment (in its various forms) and related risk perception models and tools. The work of the TA group is focused on hydro power risk, thus complementing and strengthening the activities in SCCER-SoE T4.1. The failure of a dam could lead to a catastrophic flood. This could happen during the filling of the reservoir or the operational phase of the dam itself, but also during dam construction. In Switzerland, about 200 dams exist, and ca. 25 have a height of ≥ 100 m. Furthermore, the Swiss “Energy Strategy 2050” foresees an expansion of hydropower production of about 10% with respect to current levels. Therefore, the risk assessment of possible future dam accidents is of great importance in order to reduce/avoid possible large consequences in downstream areas of dams that have high population density and/or an accumulation of high economic value objects and activities. The proposed approach within this project consists of three distinct tasks:

• Update of the Energy-related Severe Accident Database (ENSAD), the core element in PSI’s quantitative risk assessment framework In addition, the analytical approach will be further developed by including new analytical elements (e.g. Bayesian methods), and by converting the currently stand-alone ENSAD database into a flexible online tool with GIS-capabilities, thus allowing stakeholders to interactively explore various aspects of accident risks.
• A detailed probabilistic analysis of accident risk for hydropower will be carried out. This will be done at the global scale (ENSAD has a worldwide coverage of energy-related accidents) and Swiss scale (specific analysis to adapt the general results and insights to Swiss conditions).
• Finally, case studies for selected Swiss dams will be conducted, for which different dam failure scenarios will be modelled. Topography data will be collected to develop a grid for the propagation scenario of the flood wave, in terms of wave height and speed including the non-linear part (bottom friction, advection terms). The flood propagation time will be estimated to calculate a warning time downstream of the dam. This task also aims to improve the estimation of loss of lives and other consequence categories under Swiss conditions.

Summary Report: How water and geothermal energy should shape our electricity future.

The RISK GOV:  DGE & Hydro project has completed. For more information, please refer to here.