ANCHORAGE (AP) — The U.S. Department of Energy is looking for research proposals that could advance what’s known about methane hydrates. It is being considered a potential new source of fossil fuel.

Methane is the main ingredient of natural gas. The department describes methane hydrate as a lattice of ice that traps methane molecules but does not bind them chemically. Methane is released when the material is warmed or depressurized.

Methane hydrate is found on Alaska’s North Slope and in sediment on the outer continental shelf. 

The department is offering grant money for research projects in Alaska that could explore how to economically extract methane.