I heard about this a few weeks back on the news (I live in Erie, PA)
Scientific inconsistencies aside, if it saltwater was a reliable fuel source, there's no way big oil companies would allow this to go through. For years, we've been able to use cleaner fuel sources (electricity, sunlight), but we haven't switched over yet.
Same thing with the cure for cancer. There are rumors of it being developed, but the FDA would never approve such a blasphemous medication. It would hurt their money-making business of just treating cancer rather than curing it.