But more seriously, GPU loads are super spiky. Ground-based power grids and generators and batteries have trouble keeping up with them. You can go from 1MW idle to 50MW full power in 10ms. Unbuffered solar cells are right out.
That sounds like something that could be addressed in software, if necessary? Cap/throttle the GPUs according to the available power, and ramp power up/down gradually if spikiness is the issue.