The present patent incorporates major improvements and simplifications of 1976 U.S. Pat. No. 3,967,449 necessary to make the concept functional and useful on a large scale. The earlier patent listed many approaches to the several design problems believed to be necessary at the time of the earlier application, while this one reflects the extensive research and laboratory investigation to identify, validate and demonstrate the functionality of the various parts. In particular, the methods for producing the necessary nuclei for steam bubble production, the method of insuring bubble growth, the method of condensing the steam bubbles produced and methods for minimizing the release of air in large bubbles, and for dealing with those that are released are covered in detail. The first patent, with 50 claims listed many approaches to many problems, some of which were either misunderstood from an unsatisfactory literature or unnecessarily complicated. To an extent those have been eliminated, resulting in what appears to be the simplest embodiment of the concept.