Electrical white wire and bare ground. Are they both the same ground?

Yes they are at the same potential, so what you are proposing would work, however it would be against any modern electrical codes to do so.

It is much more likely that you have a loose connection in your fuse panel/breaker box.

IF there IS a break somewhere, then the whole cable should be replaced.

If it is in conduit, then pulling a new cable should be easy as long as the conduit has not been damaged.

Good luck!

There's no risk about it, you WILL energize the metal conduit and boxes in your greenhouse as well as your breaker box and any other conduit that is connected to it, now granted the current should go to ground at the first point that bare wire touches the buried conduit, but it will do so via a poor connection (bare wire loosely touching conduit) which could heat up and cause a fire as well. To say nothing of no longer having a safety ground for any of your outlets. Replace the wire.

It will work after a fashion but if your definition of 'satisfactorily' includes safety, then no. You run the risk of energizing the metal conduit and boxes in your greenhouse, which could be quite hazardous especially in a wet environment like a greenhouse.

One advantage of conduit is that you should be able to pull a new wire.

White Wire

Home wiring used to be 2 wire, 2 prong. But, If you abandon the white wire and run a hot and use the unsheilded "ground" wire as a neutral what will you connect to the ground position on your devices? At best you have no ground. The neutral carries power back to the box when needed. Be safe, fix it right.

NO! one is the grounded conductor and the other is the grounding conductor. They do both go to the same potential point in the power panel. Since this is in conduit why not just replace the wires? Install stranded wire since it is easier to pull.

If one wire is broken inside a conduit, there is a good chance the other wires are damaged as well. You best bet is to just change the wires and sleep good without worry.

No!!!!! White is neutral black is hot bare is ground. Neutral and ground may go to the same place in he break box. You could use he ground but as its not insulated its not a good idea and than ypu wouldnt have tour greenhouse grounded

The bare wire is a safety ground and the white wire is the secondary ground.Fix it right for your safety.

It is down to potential;. If you have to ask I will tell you as you will never grasp the theory of nuetral and grounding potentials.