How Is Hydrogen Made?

How Is Hydrogen Made?

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Source: The National Energy Education Project (Public Domain)
Because hydrogen doesn't exist on Earth as a gas, it must be separated from other elements. Hydrogen atoms can be separated from water, biomass, or natural gas molecules. The two most common methods for producing hydrogen are steam reforming and electrolysis (water splitting). Scientists have discovered that even some algae and bacteria give off hydrogen.
Steam Reforming Is a Widely-Used Method of Hydrogen Production
Steam reforming is currently the least expensive method of producing hydrogen and accounts for about 95% of the hydrogen produced in the United States. This method is used in industries to separate hydrogen atoms from carbon atoms in methane (CH4). But the steam reforming process results in greenhouse gas emissions that are linked with global warming.1
Electrolysis Creates No Emissions but Is Costly
Electrolysis is a process that splits hydrogen from water. It results in no emissions, but it is currently an expensive process. New technologies are currently being developed.
Hydrogen can be produced at large central facilities or at small plants for local use.
How Much Hydrogen Is Produced in the United States?
About 9 million metric tons of hydrogen are produced in the United States annually, enough to power 20-30 million cars or 5-8 million homes. Most of this hydrogen is produced in three States: California, Louisiana, and Texas.
1. U.S. Environmental Protection Agency, Climate Change State of Knowledge.