Kinetic energy = 1/2 m * v^2. Hyperloop trains wouldn't have "much" less energy, because the scaling factor on velocity is so high that your savings on train we

Kinetic energy = 1/2 m * v^2. Hyperloop trains wouldn't have "much" less energy, because the scaling factor on velocity is so high that your savings on train weight don't mean much. You are right that it would take less power.