> ”Fair comparison here is overall energy invested for energy obtained.” We think of “energy invested” as having an environmental cost, and of course that’s tr

> ”Fair comparison here is overall energy invested for energy obtained.” We think of “energy invested” as having an environmental cost, and of course that’s true when it comes from polluting fossil sources. But as grids get cleaner, and transport vehicles and construction equipment are electrified, this is no longer such a concern. Eventually we’re just using clean energy to build more clean energy - a virtuous cycle! New low-carbon concrete formulas and steel production technology are also needed, of course, since these are a major source of emissions whether for a nuclear plant or wind farm.