The Army wants to use oil-eating enzymes to power its electric vehicles

When an oil tanker spills its contents into the ocean, one way to clean up the mess is to cover the spill with enzymes that eat oil.

The U.S. Army wants to use the same process for a less benign cause: developing a high-efficiency fuel cell that can power electric vehicles and drones.

“An enzyme fuel cell is an excellent power source for electric vehicle range extension, auxiliary power, or robotic power for payloads,” notes the Army Small Business Innovation Research (SBIR) announcement.

“The technology is based on the use of enzymes to ‘digest’ hydrocarbons successfully demonstrated on the cleanup of oil spills, and on lab scale demonstrations of [Jet Propulsion grade 8] (JP-8) fuel to generate hydrogen for use in fuel cells producing electrical power,” the announcement continues.

The project seems primarily aimed at supplementing or replacing the JP-8 kerosene-based fuel widely used in military aviation. The goal is to develop an enzyme fuel cell that is much more efficient at converting fuel into energy.

Gasoline-powered automobile engines, for example, range from 20 percent to 40 percent efficiency. For military aircraft that rely on fuel cells, existing cells are limited. “Currently, large engines can get in the 40 to 50 percent efficiency range, but this is not likely using JP-8 fuel,” the Army said. “Small engines can get in the 20 to 25 percent efficiency range, but are very loud.”

Hydrogen-based fuel cells suffer from the lack of easily available pure hydrogen on Earth. This often means adding a fuel reformer to the cell to extract hydrogen from hydrocarbons and other energy sources.

“But this process is also inefficient. Current JP-8 fuel cells utilizing fuel reformer technology are large and heavy, with 30 percent efficiency,” the Army noted.

Eating their way to better engines

JP-8 refueling enzymes power up electric vehicles — Airman 1st Class Nicholas Clendenen, prepares to drain the tank of an R-11 refueling truck on RAF Mildenhall, England, so that it’s light enough to undergo maintenance. Maintaining the R-11 refueling trucks is essential to keeping up the flow of Jet Propulsion grade 8 (JP-8) fuel to aircraft and equipment. (U.S. Air Force photo by Airman 1st Class Preston Webb/Released)

The Army wants an enzyme fuel cell with at least 70 percent fuel-to-energy efficiency. The cell should be capable of generating one kilowatt of electric power. Somewhat unusually, the project is skipping the initial Phase I stage of SBIRs, which usually involves showing that the concept is theoretically feasible.

Instead, the Army is going to Phase II – demonstrating a working prototype – on the basis that the enzyme fuel cell idea is already proven to be sound through real-life applications such as the cleaning up of oil spills.

“This concept will be successful because it leverages demonstrated technology utilizing enzyme hydrocarbon digestion,” said the Army. “Engineering challenges, integration, and system scale up remain and will be the focus of this effort.”

The prototype fuel cell must successfully demonstrate an “enzyme prototype digester.” These enzymes must convert fuel into energy in a wide range of temperatures.

Ultimately, the Army aims to scale up enzyme fuel cells to produce up to 25 kilowatts, or 25,000 watts. For comparison, a small UAV might need up to 200 watts of power to operate, while a large one might need several thousand.

This technology may also be used on electric vehicles, whose limited range, and difficulty in recharging, are hampering their advent on the battlefield. “While this topic is mainly geared towards aviation use cases, the creation and adoption of this technology has the potential to significantly contribute to the commercial adoption and success of electric vehicles,” the Army said.

Michael Peck is a contributing writer for Sandboxx and Forbes. He can be found on Twitter and LinkedIn.