Highly efficient mhd generator

The laser-driven MHD converter offers high system efficiency, high power density, and closed-cycle operation. Furthermore, such a closed-cycle system can be built with few (or no) moving mechanical parts; thus it would be highly reliable and require little maintenance. A high overall system efficiency is expected because of the high conversion efficiency of the MHD generator (approximately 70 percent) and the high absorption (approximately 100 percent) of the laser beam in the working fluid.

 

https://webcache.googleusercontent.com/search?q=cache:dII1QJHWYlUJ:https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19870001331.pdf+&cd=1&hl=en&ct=clnk&gl=ca

Can mhd generators really be that efficient (70%)? If yes, why they aren't widely used yet?

Which methods could be used to dissociate water molecules present in water vapour in mhd generator?

Edited November 20, 20169 yr by Moreno