The ammonia plants at the moment are in the $100M range. I am helping with fund raising for a small company that has a solid state ammonia synthesis method which will bring the minimum plant size down to a single synthesis tube, putting ammonia production costs at a small scale in the same realm as the purchase price of a large tractor. I think that an individual turbine purchase as you suggested would be a nice thing to do, but even better would be seeding some of the things out there that just need a little bit of money to get moving. I was at the Ammonia Fuel Network conference a few weeks back and I saw several things that seemed to fit into that category.
Neal