When I hear the words “district heating,” I often think of the potential for geothermal whereby geothermal heat is captured and rather than converted into electricity, it’s used directly to heat large portions of cities. Well, Seattle is looking into district heating but it’s not targeting geothermal as the the heat source. Rather the city is looking at capturing excess heat from its plethora of data centers and using the heat in commercial buildings.

The city is in discussions with Seattle Steam and utility company Corix to use excess heat from data centers in the South Lake Union area, a location that includes the new Amazon headquarters. The district heating/data center idea has been tried in Helsinki, Finland but this is the first I’ve heard of it being tried in the U.S. I’m a little skeptical just in terms of the actual volume of heat energy that can be captured from data centers to make a system worthwhile. But I do wonder whether in cities with existing district heating systems, data centers might be able to sell their excess heat back to the grid, maybe in the same vein that net metering is working for solar.