Because the plasmoid is far from any solid surface, surrounded by lower temperature gas, melting the surroundings is not of concern, although a commercial system will need heat removal systems (particularly for the anode, which is closest to the plasmoid). Our FoFu-1 chamber does get warm to the touch after a series of experimental shots. In a potential commercial system, energy will be extracted from the ion beam that exits the plasmoid, and from the X-rays using an "onion" type device that takes advantage of the photoelectric effect over many thousands of layers. Both these methods promise very high efficiency, while eliminating any steam turbine. The video might better explain:
http://www.youtube.com/watch?v=jVif4hUAJ8c 
