Published on September 26th, 2012 | by Tina Casey7
U.S. Navy Uses Seawater to Make Jet Fuel on the Go
September 26th, 2012 by Tina Casey
Imagine a fighting force that can scavenge its own fuel as it marches along, and you’re either thinking about the Continental Army’s march to Yorktown or the U.S. Navy not too many years in the future. Scientists at the Naval Research Laboratory (NRL) in Washington are working on a process that can produce jet fuel from seawater. It sounds like something that would give the U.S. a powerful edge in action, so let’s call this Round 3 in the Navy’s efforts to free itself from dependency on fossil fuels.
Fossil Fuels and the U.S. Navy
The main supplier of fuel to Navy vessels at sea is called the U.S. Navy Military Sea Lift Command. According to the Navy, last year, Sea Lift Command transferred almost 600 million gallons of fuel to Navy vessels while they were under way.
Refueling at sea is a risky business under any conditions. Add in stormy weather and high seas, to say nothing of any kind of international situation up to and including a fire fight, and you can see how the logistics of fossil fuel delivery put a powerful burden on operations.
On top of that, the upward trend in fossil fuel prices exposes the Navy’s budget to price spikes and supply disruptions, forcing it to divert resources from other operations.
Making Jet Fuel from Seawater
The seawater comes into play as a source of raw ingredients for liquid jet fuel, namely carbon dioxide and hydrogen. Though it may seem counter-intuitive, according to NRL, drawing carbon dioxide from seawater can actually be more efficient than using airborne carbon dioxide, because the concentration of carbon dioxide in seawater is 140 times greater than in air.
To split the carbon dioxide and hydrogen away from other elements in seawater, NRL has been developing an electrochemical acidification cell based on chlorine dioxide. It works by using small amounts of electricity to acidify seawater, forming sodium hydroxide.
With the carbon dioxide and hydrogen in hand, the next step is an iron-based catalyst that NRL has tweaked to reduce the production of methane gas (an undesirable byproduct) while producing more hydrocarbons called olefins. Another step in the process converts the olefins to a liquid, and a final step using nickel-based catalysts converts the liquid to a form suitable for jet fuel.
With portability in mind, the research team has been working on a self-contained system that includes a power supply, pump and other accessories, all fitting into a movable skid measuring only 3 feet wide, 5 feet long, and 5 feet high.
So far, tests in the lab indicate that the process could produce jet fuel costing in the range of $3 to $6 per gallon. The next hurdle is to give the process a spin in open waters.
Jet Fuel from Seawater: Who Could Hate It?
Aside from the security of domestically and independently sourced fuels, non-petroleum fuel options also enable the Navy to avail itself of fuel supplies from allies around the globe. That’s especially critical as the U.S. turns its attention from the Middle East to the Pacific theater, where the Australian biofuel industry could play a key role.
With China and Japan at loggerheads over ownership of an island and Iran threatening the Strait of Hormuz, now is hardly the time for the party of “support our troops” to undermine U.S. credibility as the world’s most advanced, agile and powerful fighting force at sea.
However, that is exactly what’s happening.
Last spring, Republican leadership in Congress tried to monkeywrench the Navy’s ambitious biofuel program by prohibiting the Department of Defense from purchasing alternative fuels that cost more than conventional fuels, or from building its own biorefineries.
The Navy promptly leaped those hurdles with support from the Obama Administration, in the form of new grants for research leading to low-cost biofuels in partnership with the U.S. Department of Agriculture and new biofuel refineries built by private sector partners.
That’s why we’re calling the seawater-to-fuel research Round 3, as the Navy ramps up its efforts to insulate its fighting forces from the logistical burden of fossil fuel and the fiscal burden of global oil markets, despite pushback against alternative fuels from, primarily, leadership in the Republican Party.
Considering the politics involved, a knockout blow is probably too much to hope for. But, for now, it looks like the Navy is winning this fight.
Follow me on Twitter: @TinaMCasey.
Drive an electric car? Complete one of our short surveys for our next electric car report.
Keep up to date with all the hottest cleantech news by subscribing to our (free) cleantech newsletter, or keep an eye on sector-specific news by getting our (also free) solar energy newsletter, electric vehicle newsletter, or wind energy newsletter.