Healthy Glaciers Keep the Power Flowing

Healthy Glaciers Keep the Power Flowing

Rhone Glacier (Blake Johnson/CC-SA-BY-2.0)

Rhone Glacier (Blake Johnson/CC-SA-BY-2.0)

Joerg Schaefer’s work with colleagues, including Summer Rupper and Pierre Gentine, includes studying the impact of glacier loss on hydro and nuclear power systems. 

Glaciers act as natural water towers, dispensing melt water during peak summer months when precipitation is often scarce. That helps ensure the continuous annual water supply that efficient hydro- and nuclear power production depend on, the latter using the water as cooling agent. France, for example, relies on nuclear for about 75 percent of its power, and almost half of those power plants are cooled by the Rhone River. The Rhone also supplies about 15 percent of the country’s hydropower. During the heat waves in 2003 and 2006, water levels of the Rhone River dropped and water temperatures rose to a level that forced a shut down of several nuclear power plants. This very costly crisis triggered a variety of new research.

With support from a Crosscutting Initiative (CEI) seed fund, an inter-disciplinary group of paleoclimate, glaciology, and hydro-engineering experts is evaluating the Rhone Glacier-nuclear power nexus as an exemplary research study. Our preliminary results paint a gloomy picture: Rhone Glacier has been much more sensitive to summer temperature than to precipitation change, and rising global temperatures have reduced the estimated melt water discharge over the last century dramatically. During the summer peak months, almost all of the upper Rhone River waters, including the catchment area’s groundwater, are glacier-fed.

Our group will model these results down-stream, using simple hydro-engineering models, to quantify the changes of the Rhone Glacier meltwater reduction on the lower Rhone River level and temperature. Near-global glacier recession is one of the direct consequences of ongoing anthropogenic heating of our planet, and it is already clear that climate change has altered the glacio-hydrology in the Alps dramatically. We are evaluating to what degree the downstream hydro and nuclear power generation is impacted, despite the fully engineered Rhone River system. Our team is also studying the affects of glacier retreat on the glacier-hydropower nexus in the monsoonal Himalayas. Much more such research is needed to evaluate the impacts, quantify the costs, and eventually create a better fact-base for designing a sustainable energy concept in mountain areas with dwindling glacier meltwater.  —Joerg Schaefer

Changes in the Rhone Glacier from 1900 to 2008. Power systems downstream depend on the glacier's meltwater. (Joerg Schaefer)

Changes in the Rhone Glacier from 1900 to 2008. Power systems downstream depend on the glacier’s meltwater. (Joerg Schaefer)