Feeling the pinch of high gas prices every time you fill up your car? Be thankful you’re not the U.S. Military. Tired of wasting so much of its budget on fossil fuels, the US Navy has led the quest for greener alternatives – and scientists at the U.S. Naval Research Laboratory (NRL) have developed a process that can transform abundant seawater into fuel for Navy jets. If the technology is rolled out their efforts could have a huge impact; in 2010 alone the Department of Defense shelled out approximately $11 billion on “operational energy,” the energy used by military forces in the execution of their field missions. That’s the equivalent of the entire budget of the state of Tennessee. And that doesn’t even include all the energy needed to power vehicles and military bases here at home.
According to a recent NRL announcement, the transformation takes place during a unique gas-to-liquid process that extracts carbon dioxide from seawater, eventualy producing hydrogen gas using an electrochemical acidification cell. “The reduction and hydrogenation of C02 to form hydrocarbons is accomplished using a catalyst that is similar to those used for Fischer-Tropsch reduction and hydrogenation of carbon monoxide,” said Dr. Heather Willauer, a research chemist.”By modifying the surface composition of iron catalysts in fixed-bed reactors, NRL has successfully improved C02 conversion efficiencies up to 60 percent.”
At NRL’s Center for Corrosion Science & Engineering facility, Key West, Fla., (NRLKW) a prototype carbon capture skid has been tested using seawater from the Gulf of Mexico to simulate conditions that will be encountered in an actual open ocean process for capturing CO2 from seawater and producing H2 gas. Currently NRL is working on process optimization and scale-up. Once these are completed, initial studies predict that jet fuel from seawater would cost in the range of $3 to $6 per gallon to produce.
It makes sense that the Navy would look to transform seawater into an energy source. First, it’s convenient, as most of the Navy fleet is deployed on an ocean somewhere across the globe. Second, seawater is rife with C02, with ocean concentrations about 140 times greater than that in air. Although the conversion process has made significant advances in the past few years, it’s far from being implemented. Still, with global oil supplies dwindling by the day, it’s no surprise that the Navy is trying to plan ahead.