Imagine an aircraft carrier being able to turn seawater into an endless supply of fuel for fighter jets.
A Texas company backed by the U.S. Office of Naval Research plans to do some potentially groundbreaking work on the process of making jet fuel from seawater at a state technology park on Hawaii island.
Sea Dragon Energy Inc. is proposing a research and development project to make small quantities of jet fuel from seawater and hydrogen at the Natural Energy Laboratory of Hawaii Authority.
The work is expected to cost about $16 million and last two to five years. Success, if realized, could advance the scientifically sound concept of creating fuel solely from elements in seawater closer to commercialization.
“This is a major step on the path toward truly sustainable aviation fuel for both government and commercial use,” John Kohut, Sea Dragon’s chairman and CEO, said in a statement in August after the Office of Naval Research awarded the company a $19.2 million contract to design and build the testing unit.
In September, the company published a draft environmental assessment as part of its plan to do the research and development work in a warehouse, office and lab complex formerly occupied by a company that used the tech park’s source of deep seawater off Kailua- Kona to produce desalinated bottled drinking water and research on health products derived from nutrient-rich seawater drawn from 3,000 feet below the surface.
Laurence Sombardier, NELHA’s deputy director, said the agency’s tech park is ideally suited for developing innovative technologies in the areas of ocean science and renewable energy.
“The concept is indeed very novel, utilizes the park’s marine resources and while the technology is in its infancy, producing fuel from sea water could be of high interest to island nations and communities,” Sombardier said in an email.
Advancing technology
Sea Dragon’s plan is to produce one roughly 10-gallon batch of jet fuel per month. An analysis of each batch would inform adjustments to production variables and improvements to equipment for subsequent batches.
Methods to make jet fuel from seawater have been understood and demonstrated for many years, but are far from feasible large-scale production.
Essentially, the process removes carbon dioxide and hydrogen from water and converts those two gases into a synthetic liquid hydrocarbon fuel.
According to the U.S. Naval Research Laboratory, one of the lab’s research chemists developed one such process that received the top honor in 2014 from Popular Science magazine.
Fuel made from that process, referred to as an Electrolytic-Cation Exchange Module, was used at the time to fly an off-the-shelf radio-controlled aircraft powered by an unmodified two-stroke internal combustion engine, the lab said.
However, designing catalysts needed to efficiently use the process to make lots of jet fuel has been difficult and costly, according to the University of Pittsburgh and the University of Rochester, which in 2021 received $300,000 from the Office of Naval Research to improve the process.
The same proprietary and patented Naval Research Lab process is part of what Sea Dragon is to use in its planned work, though the company would obtain hydrogen from the tech park or another supplier instead of using electricity to extract it from seawater.
Extracting hydrogen from water is not the big challenge to advance the goal of making jet fuel from seawater, but removing carbon dioxide and efficiently producing the fuel from the two gases is.
“In general, they are fairly energetic processes and difficult,” said Richard Rocheleau, director of the Hawai‘i Natural Energy Institute at the University of Hawaii. “They require a good bit of energy.”
Rocheleau said the Big Island tech park provides advantages for trying to advance seawater-to-jet fuel work because of the infrastructure there and the relative purity of the seawater.
Production steps
To make a 10-gallon batch of jet fuel, Sea Dragon would use roughly 449,000 gallons of seawater, 50,000 gallons of fresh water and 154 pounds of hydrogen in an initial step to remove most of the carbon dioxide from the water, which the company said would contain no pollutants and be deposited into the ocean through the tech park pipe system.
A second step would involve using hydrogen and electricity to convert the carbon dioxide into carbon monoxide, a process the company said would generate 80 gallons of water expected to be similar in quality to tap water. This water would be tested to ensure it can be recycled, or treated before disposal if necessary.
A third step would use metal catalysts and electricity to convert the carbon monoxide with hydrogen into synthetic petroleum. Sea Dragon said in its draft environmental assessment that byproducts in this step would be water of the same quality as in the prior step along with a small amount of hydrocarbon gases that would be combusted as a low-flow flare.
The last step would be to refine the synthetic petroleum into jet fuel using hydrogen and electricity. Hydrocarbon gases also would be a byproduct of this step and combusted as a low-flow flare. Sea Dragon said in its environmental report that such gases from the third and fourth steps would be equivalent to one gallon of fuel.
The company also said that the jet fuel will be tested, stored indoors with spill protection, and limited to no more than 120 gallons stored.
Ambitious goals
If the work is successful, it would help with possible development of a larger mobile fuel production unit. One ultimate goal is to create commercial-scale production units that could be installed in places including remote locations and on aircraft carriers.
According to Sea Dragon, preliminary studies suggest that a seaborne version of such a unit could sustain operations of a carrier strike group indefinitely, creating a huge advantage for the Navy.
The company also touts other benefits from feasible commercial production if it is one day achieved.
“SDEI believes that decentralizing and distributing energy production and storage will increase resiliency, support sustained renewable generation growth, and help address the challenges of climate change through a range of potential applications in the private and public sectors,” Sea Dragon said in the draft environmental report.
If the environmental review and permitting proceed without complications, Sea Dragon anticipates that research and development operations could begin in 2026.
