I like the fact that there is continued interest in New types of engines. Maybe the materials at hand now can accommodate these types of stresses, where as, 20 years ago, there weren't the processes of foundry that are available today. I'm excited to see how far they take it.
Most of the energy that is produced by an internal combustion engine, is both blown out the exhaust as unburned fuel and heat. If it where possible to harness and make use of those wastes, you'd really have something there!
Ron