U.S. Department of Energy - Energy Efficiency and Renewable Energy

Fuel Cell Technologies Office – Hydrogen Production

Thermal Processes

Some thermal processes use the energy in various resources, such as natural gas, coal, or biomass, to release hydrogen, which is part of their molecular structure. In other processes, heat, in combination with closed-chemical cycles, produces hydrogen from feedstocks such as water—these are known as "thermochemical" processes.