I was thinking tera or exa watt output would be needed, which is less than our global energy consumption, but hilariously more than any individual power plant could produce, regardless of whether it's fission, fusion, natural gas, or coal.
An antimatter powered generator might be able to hit the mark, but good luck with that; both building an antimatter power plant, and creating enough antimatter in the first place
Yes, it all works in theory and in the lab, but in practice we have no idea if cloud seeding "makes it rain" or if it would have rained anyway (to make a long story very short).
So take anything anyone says about "them making it rain" with, like, two grains of salt.