SPEAKER: Jeff Witter, Ph.D Geothermal Geologist / Project Geophysicist, S.J.V. Consultants Ltd.
TITLE: Volcanic Hazards and Geothermal Development
DATE: Thursday, May 24, 2012, 4:30pm
LOCATION: Room 451, 409 Granville (UK Building at Granville and Hastings)
Abstract: Volcanoes can be attractive for geothermal energy developers thanks to the high temperature resources often found beneath them. However, volcanic eruptions and their effects pose a significant hazard to geothermal development and infrastructure. Examples of volcanic phenomena which can have a negative impact on geothermal power operations include: ash fall, lava flows, pyroclastic flows, lahars and sector collapse. In general, siting of geothermal installations is critical to avoid many volcanic hazards. In some cases, though, exploiting a geothermal resource and siting infrastructure outside of volcanic hazard zones may be incompatible. A review of the literature suggests that direct impacts of volcanic eruptions on geothermal infrastructure have so far been limited. However, in the world’s top ten geothermal energy producing countries there is a clear positive correlation between the number of volcanoes with Holocene eruptions and geothermal MW capacity. Planned increases in geothermal development worldwide in the coming decades, coupled with the attractiveness of volcanically-hosted resources, suggest that volcanic hazards will become an increasing concern to developers. Fortunately, scientific researchers have recently developed a Bayesian event tree scheme to perform complete probabilistic volcanic hazard assessment for individual volcanoes. This method combines the probabilities of: an eruption, the occurrence of different types of hazardous volcanic phenomena, and the impact on specific areas that lie at specific distances from the volcano. A probabilistic volcanic hazard assessment can be quite useful to geothermal developers to help limit financial losses as it provides a quantification of the magnitude of volcanic risk for the project. These results can then be directly compared to other natural and non-natural sources of risk which can help senior management, investors, and others make informed risk decisions when working on geothermal projects in volcanic areas.