[NonZeroSum]

But the point of the space elevator is that it reduces the cost of transportation to a little above the basic energy costs, so I don't understand your original comment.

[John Jamieson]

Just HOW does it do that?

You can't just pullup a payload without throwing yourself out of obit. The payload has to be boosted up the line, same as it would be without the line.

Now if you happen to have an infinite supply of mass already at the top end, you can send down the same amount as your pulling up and remain stable.

There ain't no free lunch (or launch, either).