Ok, I'm not a physicist, but here's my take on things.
Let's assume you've got a station or whatever in geo orbit, and you've got a very strong lightweight cable.
If you carry a rock to the top of a building, you are increasing it's potential energy. All the effort you put into hefting it up is "stored" in the rock.
Orbit is a trick by which you spin around the earth, thus rotating the direction of gravity, and thus preserving your potential energy while spinning around. The point: the amount of energy it took to "lift" it into orbit is still there.
So, to lower your fancy fan assembly manufactured free of defects in zero-g, you need to exert as much energy as was needed would be needed to heft it to begin with.
The space shuttle uses all that juice in the big bottle to get into orbit; and it uses drag to return. This is why the space shuttle has a very low operating altitude. If it's too far up, it's little reserve of fuel is not enough to slow it to the point it drag can take over.
Thus, because of all this energy expenditure, I believe a space elevator is of little use.
Of course, I'm not a physicist, so be nice to me, ok?
