U.S. Marines tested prototypes of solar-powered drones along with other concept technologies at an energy-saving expo in Camp Lejeune, N.C. last week.

The Tactical Long Endurance UAS, or "TaLEUAS," is a solar- and thermal-powered drone glider designed for high-altitude reconnaissance, surveillance and intelligence operations. Made by the Naval Research Lab in Washington, D.C., and the Naval Postgraduate School in Monterey, Calif., the system utilizes sensors that locates thermals in the atmosphere, according to the Marine Corps Times.

From June 23 to June 25, about 200 East Coast Marines were able to sample the TaLEUAS and other gear prototypes at the annual Expeditionary Energy Concepts demonstration, formerly known as the Experimental Forward Operating Base or ExFOB.

Also displayed was a ballistic body armor plate insert that doubles as a battery for Marine equipment, an electric all-terrain vehicle and a gear system comprising a backpack and knee braces that harvest kinetic energy from a Marine's movements and includes an individual water filtration system.

The expo derives from the 2011 Expeditionary Energy Strategy of Gen. James Amos, the 35th Commandant of the Marine Corps.

According to the Marine Corps, "The overall goal for the Expeditionary Energy Office is to help the Marine Corps find new, innovative solutions for energy efficiency in the battlefield and to increase operational reach and combat effectiveness."

Col. James Caley, director of the Expeditionary Energy Office, said the expo was a good deal for the Marines and the Department of Defense.

"We haven't spent a dime," Caley said. "These companies have spent their money to build prototypes for the Corps. We are getting the best ideas from industry with their initial investment."

Attending Marines came from 20 different military occupational specialties and were asked to fill out surveys about the gear they sampled in order for the Corps to determine what would be selected for future testing and development.

"We want the Marines giving their input," Caley said. "It's not as easy as handing them something cool; it has to be useful. We want the Marines to use the solutions we present them."

The finished product of the TaLEUAS is expected for completion in 2016, and developers are planning a concept demonstration of the system later this year.