Northwest Energy Association

NWEA Speaker Program for 2017-2018

May 17, 2018 Luncheon

Energy-related thesis presentations by Portland State Graduate Students.

Is there Geothermal Potential in the Portland Metro Area?

by Ellen Svadlenak, Darby Scanlon, and Alison Horst (all Portland State University)

Deep direct-use thermal energy storage (DDU-TES) is a low carbon method of heat storage and supply that has potential within the Portland Basin. DDU-TES supplies buildings with hot water for heating during the winter or cooling during the summer via seasonal cycles of hot/cold water injection, storage, and subsequent extraction from evolved groundwater within the Columbia River Basalt Group. Though a promising technology, DDU-TES cycles may trigger or accelerate mineral dissolution and precipitation that can reduce operation efficiency. One aspect of this research addresses hydrogeochemical concerns by modeling the interactions between reservoir rock and heated water to determine the extent to which DDU-TES induced processes may impact reservoir properties and system components. Depth to the target reservoir and hazards posed by active faults within the basin also need to be evaluated before DDU-TES can be implemented. A second aspect utilizes existing well log, seismic, outcrop, and potential fields data to define the geometry of the Portland Basin, track basin depocenters, and construct isopach maps to better understand the depth to reservoir and basin history. A third aspect focuses on characterizing faults in the Portland and Tualatin Basins to refine basin geometry and assess seismic hazard in the region with a focus on estimating the most recent rupture along the Gales Creek fault through a paleoseismic trench and radiocarbon dating. This research is improving our understanding of the hydrogeology, stratigraphy, and structure of the Portland Basin, critical for both development of DDU-TES resources and an improved geologic understanding of the region.