These wings are obviously very thin, light and flexible. The battery is also a lithium-polymer one, which can deliver a lot of power for a short duration (eg: 20 watts for 5 minutes). With current tech, it wouldn't be possible for this robot. I also don't think it would be possible for this robot to generate enough power to keep flying continuously, even if you had 100% efficient ultra-light solar cells.

All of that being said, there are solar-powered drones with large static wings out there, typically based on glider designs. We can also imagine a design where a drone lands and recharges using solar power for ten minutes, and then flies for a short one-minute trip. With the fly-inspired design in this video, it could probably take off vertically.

No. Not enough ratio of surface area to volume.

One of the reasons these systems (and their insect inspirations) can fly so nimbly, while a jumbo jet or elephant is more plodding in comparison, is the "cube/square law" - an object increases in weight much more quickly than it increases in area, and it in reases in area much more quickly than it increases in length.

You can get a decent ratio of volume (weight and chemical power storage) to surface area and heat dissipation/respiratory potential with tiny systems. If you want a lot of area (solar power insolation), you need to go bigger and slower.

I don't know that it would be possible with this design. The wings are a kind of plastic sheeting. They kinda look like bits of shower curtain, actually