> with enough power you could just push the air around any way you like
Maybe a real god could, but we can't. Unless you have tractor beams, anti-gravity force fields and other sci-fi tech, either you'd have to have these "weather machines" placed in a fairly tight grid, or intractability would rule (outside a small area of influence). The problem isn't just energy, but directing it.
Also, the inefficiency of ex: wind turbines would add a lot of energy which would be counter productive. You might be able to control the weather by blocking out the sun and then selectively lighting some areas over others. But that's not really controlling weather so much as setting the temperature on an AC.
Maybe a real god could, but we can't. Unless you have tractor beams, anti-gravity force fields and other sci-fi tech, either you'd have to have these "weather machines" placed in a fairly tight grid, or intractability would rule (outside a small area of influence). The problem isn't just energy, but directing it.