Navy hasn’t discovered the Holy Grail of energy independence yet using seawater as fuel. Here is the story.

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A while back, the Navy announced plans to turn seawater into fuel, thereby eliminating our dependence on fossil fuels — and despotic regimes — and discovering the Holy Grail of energy independence. And no one’s talking about it.

Well … turns out there’s a good reason for that.

See: Engineering Newswire: Naval gas from seawater

Sure, the news broke back in April, but a momentous discovery like this should still be plastered across every newspaper in the country. The end of fossil fuels. The renewable energy bombshell we’ve all been waiting for. But less than a year later, no one cares.

Back in April, the political website Addicting Info ran the headline “The U.S. Navy Just Announced The End Of Big Oil And No One Noticed.” “Curiously, this doesn’t seem to be making much of a splash (no pun intended) on the evening news. Let’s repeat this: The United States Navy has figured out how to turn seawater into fuel and it will cost about the same as gasoline,” they wrote. “Why this is not a huge major story mystifies me,” pondered the author.


The USS Nimitz on maneuvers. Could our Navy one day be powered entirely by seawater?

The Navy’s process essentially involves pulling CO2 and hydrogen from seawater and converting it into liquid hydrocarbon “jet fuel”. Addicting Info opines that this procedure could put a serious dent in climate change, since the process “pulls carbon dioxide (the greenhouse gas driving Climate Change) out of the ocean,” and the ocean already has too much of the poisonous stuff.

And in conclusion, the process would fundamentally transform the Middle East, especially the regimes which make a (literal) killing from oil profits. “And if we ‘leak’ the technology? Every dictator propped up by oil will tumble almost overnight,” notes Addicting Info.

Unfortunately, the Holy Grail of Energy Independence will have to wait. As Vice News points out in the piece “Sorry, Everyone, Making Fuel Out of Seawater Isn’t Gonna Save Humanity,” one of the major enabling technologies is nuclear power. Indeed, a 2010 report from the Naval Research Laboratory points out that “two scenarios for producing electrical power for the jet fuel process at sea are the Ocean Thermal Energy Conversion (OTEC) process and nuclear power.”

Oh, and in order to synthesize the 100,000 gallons/day of jet fuel required by the Navy, we’d need to process a lot of seawater — about 8,900,000 cubic meters/day. According to the Navy’s report, “This is equivalent to a cube of seawater that is about 200 meters on each side.”

Assuming the process is 100% efficient — and it never is — we’d only be able to process about 60% of the CO2 extracted from the seawater, and the fuel produces electricity, we’d use more energy than we’d save.

Four years ago, the Navy concluded that — with an electrical process — “there is no surplus of energy” and “The overall energy balance would be unfavorable with the produced liquid hydrocarbon fuel being a little over half the energy of the entire process needed to produce the fuel.”

So we’d have to lean on nuclear power. And there appears to be a theoretical cost savings. The Naval Research Laboratory notes that “production of electricity ($0.07/kwhr) or jet fuel ($5.74/gallon) by current Navy nuclear reactor technology is less expensive to produce than the electricity ($0.12 kwhr) or jet fuel ($8.70/gallon) produced by the LM OTEC process.

But in order to produce jet fuel from seawater, you’d have to forgo electricity. And using current OTEC and Navy nuclear power to produce fuel costs about $6/gallon – more than twice as much as what the Navy pays now. We’d be banking on the fact that the logistics of delivering the cheaper fuel — at $2.80/gallon — would even out the price discrepancies. And also that the price of crude oil increases dramatically over the next decade.

This was back in 2010, and little has changed. And the environmental benefits aren’t as rosy as they first appear. In fact, the seawater conversion process would introduce more methane into the atmosphere — about 25% of the extracted CO2 would come out as this harmful greenhouse gas.

I’d love to be able to shout from the rooftops the end of fossil fuels. But this ain’t it.

Henry Sapiecha

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