Hydrogen
Hydrogen is the simplest element on Earth. A hydrogen atom consists of only one proton and one electron.
It is also the most plentiful element in the universe.
But despite its simplicity and abundance, hydrogen doesn't occur naturally as a gas on Earth. It is always combined with other elements. Water, for example, is a combination of hydrogen and oxygen. Hydrogen is also found in many organic compounds, notably the "hydrocarbons" that make up fuels such as gasoline, natural gas, methanol, and propane.
To generate electricity using hydrogen, pure hydrogen must first be extracted from a hydrogen-containing compound. Then it can be used in a fuel cell.
It is also the most plentiful element in the universe.
But despite its simplicity and abundance, hydrogen doesn't occur naturally as a gas on Earth. It is always combined with other elements. Water, for example, is a combination of hydrogen and oxygen. Hydrogen is also found in many organic compounds, notably the "hydrocarbons" that make up fuels such as gasoline, natural gas, methanol, and propane.
To generate electricity using hydrogen, pure hydrogen must first be extracted from a hydrogen-containing compound. Then it can be used in a fuel cell.
Hydrogen Fuel
Hydrogen Fuel Hydrogen is a clean fuel that, when consumed, emits only water and oxygen. It can be made from a variety of domestic sources, such as coal, natural gas, nuclear power, and renewable power. This makes it an attractive fuel option for transportation and electricity generation applications.
However, unlike other fuels, hydrogen is an energy carrier. This means that hydrogen fuel is much like a battery. It does not contain inherent energy but can be used to store, move, and deliver energy produced from other sources. The energy in hydrogen fuel therefore is transferred energy derived from the fuels and processes used to produce the hydrogen.
Today, hydrogen fuel can be produced through several methods. The most common methods are thermal, electrolytic, and photolytic processes. Thermal Processes Several thermal processes are viable for near- and mid-term hydrogen production:
Photolytic Processes Photolytic processes use light as the agent for hydrogen production. Photobiological processes use the natural photosynthetic activity of bacteria and green algae to produce hydrogen. Photoelectrochemical processes use specialized semiconductors to separate water into hydrogen and oxygen.
Content Credit: U.S. Department of Energy - Office of Energy Efficiency & Renewable Energy
However, unlike other fuels, hydrogen is an energy carrier. This means that hydrogen fuel is much like a battery. It does not contain inherent energy but can be used to store, move, and deliver energy produced from other sources. The energy in hydrogen fuel therefore is transferred energy derived from the fuels and processes used to produce the hydrogen.
Today, hydrogen fuel can be produced through several methods. The most common methods are thermal, electrolytic, and photolytic processes. Thermal Processes Several thermal processes are viable for near- and mid-term hydrogen production:
- Steam reforming uses heat to create pure hydrogen by separating it from hydrocarbons such as natural gas, coal, methanol, or even gasoline. Today, about 95% of all hydrogen is produced from steam reforming of natural gas.
- Gasification technologies use coal or biomass (organic material) to generate fuel gas that can also be reformed into hydrogen.
- Reforming of renewable liquid fuels, similar to natural gas reforming, uses biomass-based liquid fuels as an energy source.
Photolytic Processes Photolytic processes use light as the agent for hydrogen production. Photobiological processes use the natural photosynthetic activity of bacteria and green algae to produce hydrogen. Photoelectrochemical processes use specialized semiconductors to separate water into hydrogen and oxygen.
Content Credit: U.S. Department of Energy - Office of Energy Efficiency & Renewable Energy