Pretty interesting platform.
Looks to have around 16x300W solar panels, so roughly 4.8KW. A lot but no unreasonable given it has 4 electric turbines and it would take a lot of grunt to influence a balloon of that size especially given air density altitude.
If it is a civilian craft it's either government or maybe one of the big Chinese universities.
Supporting the spy angle is the pretty obvious connectivity (looks to be Ku-band satellite or similar) but it also doesn't really make that much sense... surely a satellite does what this does but better? China has no shortage of high quality spy satellites.
I don't think it's obvious what the purpose is. It's clearly very large, probably reasonably pricey. The platform alone has ~100k of solar on it, probably another 80k in propulsion, power systems and connectivity.
By no means is it outside the means of civilian agencies or even private companies in China. Given the cost of high resolution civilian aerial imagery this actually looks pretty compelling vs aircraft or satellite (which lack the resolution of normal aerial photography platforms).
The other thing is that it stands to reason is that if you build this thing, regardless of it's purpose it's going to circle the Earth pretty much no matter what. Except if you deliberately down it of course. A balloon this big, up this high isn't coming down and that propulsion system isn't going to have enough authority to choose which continent you fly over.
Anyways, super interesting. Maybe we see legit commercial implementations of this sort of platform in the coming years though it seems like it will be good fun trying to register these with all the various airspace it will inevitably fly through if you launch it.