From the Tennessee to the Columbia rivers, hydroelectric dams have played a decisive role in making cheap electricity widely distributed throughout the North American economy. From declining fish populations to flooded land, some Canadians and Americans have had to pay a higher price to make hydro power possible.
That social trade-off is making less sense today as the levelized cost of energy (LCOE) from wind and solar generation has now dropped below the LCOE of hydro and most all thermal energy resources. The portion of a U.S. state’s power generation by hydro no longer predicts its electricity prices.