> Similarly hydroelectric dams contain water by volume but you only need to dam a cross-section of the valley. I would caution that the cost of a dam does not

> Similarly hydroelectric dams contain water by volume but you only need to dam a cross-section of the valley. I would caution that the cost of a dam does not increase linearly, either (and that most resources that are profitably dammable at utility scale have already been dammed)