You could search coal auger, several posts on the subjuct, here is one,http://nepacrossroads.com/about5516.html#p53431
In the posts above they have linked to another topic with a Youtube video link showing a flexible auger loading a bin.
Most of the auger work discussed on this forum is in topic, Venting, Plumbing, Chimneys, Controls, Coal Bins
GeorgiePorgie seamed fairly low key, but I didn't read all his work, he definaltly put in the effort to build and film his auger.
Basically is looks like augers do a fairly good job moving coal, thats how it gets from my coal hopper into my fire, at a very slow metered rate.
I thing the mayor has a post about delivering coal into an auger with his delivery truck.