That video link is amazing - here's another one.
https://www.youtube.com/watch?v=YyKIZPuepl8The fact that it circulates itself with the boiling and condensing back into the pool is awesome. Just need some way to get the heat out of the tank. One of them uses a water circulated external cooler to cool the area inside the sealed tank. Some of the review videos look more like an open tank setup with condensation bars which are removable - probably more manageable than the sealed off tank. Not sure how much 'pressure' there is or if it's more of an atmospheric chamber of low pressure. Very fascinating.