Renewable Hydrogen

Hydrogen is the most abundant element in the universe. While hydrogen gas does not occur naturally on earth, it can be made from a variety of domestic sources, such as coal, natural gas, nuclear power, and renewable power. When consumed, hydrogen produces zero emissions besides water vapor, which makes it the ultimate clean fuel.

However, according to the U.S. Department of Energy (DOE), Hydrogen is an energy carrier, not an energy source. This means that hydrogen does not contain inherent energy as other fuels do, but can be used to store, move, and deliver energy produced from other sources. The energy in hydrogen is therefore considered to be transferred energy derived from the fuels and processes used to produce the hydrogen.

Since hydrogen is so plentiful in our environment, it can be produced from a variety of local resources like water, plants, coal, natural gas and even algae. Additionally, various technologies can be used to produce the power needed to release hydrogen from these resources, including fossil fuel combustion, nuclear power and renewable technologies such as solar, wind, hydropower, bioenergy and geothermal.

With the exception of hydroelectric power, less than 1% of the electricity generated in the U.S. today is produced by renewable energy - primarily because of costs. However, the advantages of producing hydrogen from renewable sources are immense, and the advancements associated with these technologies are continually improving, which can contribute significantly in producing hydrogen from renewable energy sources. Today, this is achieved most commonly through a process that uses electricity to separate water into hydrogen and oxygen called an electrolysis.

Renewable Hydrogen and Electrolysis

Electrolysis basically separates water into its various elements - hydrogen and oxygen. It does this by charging water with an electrical current, which breaks the bond between hydrogen and oxegen. When this is done using renewable energy sources, the renewable source becomes more valuable and can meet a variety of needs, since hydrogen produced during off-peak hours can be stored and used to provide reliable power throughout the day. This means that various types of clean renewable energy resources can be used to meet the many different transportation needs that we have, to provide emission-free fuel for vehicles, to provide reliable stationary power (where renewable energy sources can provide constant power), as well as provide portable power when and where needed to name just a few of the applications.

The various options available for using renewable energy source to produce hydrogen makes renewable-hydrogen systems effective in providing flexible, reliable energy in whichever form is needed most. When compared with energy storage in batteries, renewable-hydrogen systems are more practical and less costly. Other available energy storage systems (e.g.; pumped water systems, compressed air systems, etc.) are generally limited to geographical areas.

Conclusion

Currently, most hydrogen produced in the U.S. is from fossil fuels. However, the future goal for producing hydrogen on a wide-scale from renewable energy sources is fast approaching. Hydrogen can help renewable electricity technologies mature and become more cost-competitive. Until the time when renewables are used on a wide-scale, the production of hydrogen from fossil fuels can lower costs, and help to establish new and innovative methods to capture and store greenhouse gas emissions to provide hydrogen while minimizing environmental impact.

Renewables provide an emissions-free way to produce hydrogen through electrolysis, and hydrogen, on the other-hand, offers a way for renewables to generate transportation fuel and reliable power. The advantages that these offer, along with the environmental benefits of each make these a good solution to meet future energy needs.

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