There really are few drinks as refreshing as a cold glass of water, but many don't realize what else is in that cool glass ready to get gulped. There is energy in there, for one thing.
But you can bet the U.S. Navy knows this. I read where they are exploring technologies to coax enough energy out of seawater to run their ships. Think of the advantages they would have by not needing to refuel. Not to mention the cost and time savings.
What they are looking into is extracting carbon dioxide and hydrogen from the seawater under the ship and turning these elements into J-5 jet fuel. The trick is to do it at a rate that equals or exceeds their rate of usage in their critical operations modes.
As most know, it takes energy to do the extraction and then the conversion - a fact not lost on the Navy. They report that the hydrogen production part of the process alone will take 60% of the total energy available in the produced product. And where will this energy come from? The two most likely sources are from ocean thermal energy conversion (OTEC) or nuclear power from onboard reactors. Before you get too excited, the Navy is expecting an 8-10 year time frame before any of this may even get tested. And that's assuming funding can be found and a cost-effective process can be developed.
First it was NASA turning to water for future mission use, now it appears to be the U.S. Navy. I suppose next we'll hear from Detroit?! One thing is for sure, if all our energy needs are eventually going to come from water, I'll bet the water supply shortages are going to get worse. Of course, if all our water needs are going to come from the ocean, that should help keep the sea-level rise in check.
Finally, for those who claim the Water/Energy Nexus is the next big thing, it sounds like you might be right.