When Elon Musk speaks about the future, the world listens—whether it’s about colonizing Mars or building tunnels beneath cities. This time, his sights are firmly set on something closer to home: our planet’s energy consumption. In a recent post on X (yes, that’s what Twitter goes by these days), Musk painted an ambitious picture of humanity powered entirely by solar energy, hinting that such a shift could catapult us up the famed Kardashev Scale.