a feature this week on which cities around the world are doing the best at phasing out power from fossil fuels. Scanning their table, I see that the cities doing best by this metric mostly rely on hydropower, that is, on dams. In other contexts National Geographic has been a big supporter of dam removal, and they wrote a skeptical piece on Brazil's plan to generate power with a huge system of new dams on Amazon tributaries. Well, which is more important? Free-flowing rivers or reducing CO2 emissions?
At this point in time I lean toward reducing CO2 emissions. But whatever we choose, we have to recognize that there is no free lunch anywhere.