[sandworm101]

Refuelling sats won't ever be a thing. There is no real need. Any refuelling vehicle will need it's own propulsion/rcs system and a docking scheme. Once docked and/or latched onto the target ... job done. The refuelling vessel becomes the new orbital manoeuvring system for the depleted sat. Cost wise, that makes more sense than having a large tanker bouncing around between clients. With the switch to ion propulsion total fuel may also not be the limiting factor. Ion thrusters can become very inefficient and/or useless after years in space. Flying up and bolting on a new rig is simpler than trying to actually service/replace such parts.

[gibsjose]

Refueling satellites will absolutely be a thing :) Restore-L is going to do just that in 2020-2021, and do it autonomously to boot.

I work on Restore-L and believe me, there is a huge need for on-orbit satellite refueling and reservicing. The vast majority of satellites reach their end of life due to depletion of fuel, not due to electrical problems or sensor issues. This will be a huge business one day.

[sandworm101]

But will sats be refueled or will they simply have new service modules attached to them, bypassing all the tricky plumbing issues?

[colechristensen]

They will be refueled.

https://sspd.gsfc.nasa.gov/restore-l.html