Comment by Figs
7 hours ago
Hmm. Couldn't you put solar panels on top for power (and fly above the clouds) + use some sort of sail when wind is available? It might be really slow, but if you can get the systems to be fully autonomous (no people needed to pilot it) and need very little / no fuel... then couldn't it become a rather cheap way to ship things that aren't urgent?
Solar panels don't have good enough power to weight ratios and aren't likely to contribute effectively.
As far as sails go, you need a second medium to act as a keel, otherwise it's impossible to get a net push in any direction other than downwind.