Our society needs more and more energy to accommodate an ever-increasing population. According to the Energy Information Agency's (EIA) most recent predictions, global power consumption will rise about 28% by 2040. Unfortunately, in a power grid reliant on coal and oil, this will inevitably lead to more CO2, aggravating climate change. Decarbonizing the Earth, however, will see tremendous progress by 2050. Our power grid will be more efficient, sustainable, accessible, and powered by clean energy sources like green hydrogen.
Green Hydrogen Leverages Renewable Energy to Produce Clean Fuel
Producing green hydrogen relies on electrolysis, a technique that separates the hydrogen and oxygen in water by using an electrical current. Provided the electricity comes from a renewable source, we can create hydrogen fuel without spewing carbon dioxide into the environment. The result is a reactive, light, and abundant fuel that parts of our existing infrastructure can accommodate.
According to the International Energy Agency (IEA), using electrolysis to create green hydrogen could avoid emitting 830 million tons of CO2 per year, which would otherwise be expelled when making hydrogen with fossil fuels (a product known as grey hydrogen).
Unfortunately, replacing all grey hydrogen in the globe would need 3,600 TWh/year of additional renewable power, roughly equal to Europe's total energy consumption rate. Moreover, there are other concerns regarding the practicality of green hydrogens, such as high costs. Nevertheless, these obstacles will diminish as decarbonization proceeds, and renewable energy becomes less expensive.
Green Hydrogen Requires Electricity, Water, and High School Chemistry
The electrolytic process that makes green hydrogen uses renewable energy to separate the hydrogen and oxygen molecules in water (H2O). Producing green hydrogen requires four steps:
- The water source must contain the correct levels of minerals and salt to conduct electricity.
- Two electrodes connected to a renewable power supply enter the water, emitting a direct current.
- The electrodes attract ions of the opposite charge.
- As the ions move, an oxidation-reduction reaction produces hydrogen (H2) molecules on the reduction side and oxygen molecules (O2) on the oxidation side.
Hydrogen Fuel Has a Long History That's Gaining Steam
The most prevalent chemical element in nature is hydrogen, making it an abundant resource. And worldwide demand for hydrogen fuel has tripled since 1975, according to the IEA, reaching 70 million tons per year in 2018. Furthermore, unlike coal and oil, green hydrogen is a clean energy source that produces only water vapor and causes no greenhouse emissions.
Hydrogen has seen industrial use for a very long time. Since the nineteenth century, people have used this gas to power machines, automobiles, airships, and spacecraft. The global economy's decarbonization, a crucial goal, will elevate hydrogen's profile. Furthermore, if its manufacturing costs are reduced by half by 2030, as forecasted by the World Hydrogen Council, hydrogen will surely become one of the most important fuel sources over the next several decades.
Using Green Hydrogen Has Advantages and Disadvantages
As with any fuel source, hydrogen has qualities that recommend it, along with some that may prove to be obstacles. The most important advantages of hydrogen fuel are -
- Versatility – We can convert green hydrogen into energy or synthetic gas and utilize it in commerce, industry, or transportation.
- Sustainability – The manufacturing and combustion of green hydrogen emit no GHGs to pollute the atmosphere.
- Storability: We can build a stable supply of hydrogen to use whenever we need it because we have the technology to store it long-term.
However, there are certain disadvantages to using green hydrogen that we must overcome in the future -
- Energy – Hydrogen requires more energy to produce than most other fuels. This requirement is exceptionally high for green hydrogen.
- Cost – It is more expensive to produce renewable energy than fossil fuels. Therefore, powering electrolysis to make green hydrogen is costly as well.
- Safety - Because hydrogen is a volatile and highly flammable material, substantial safety precautions are necessary to avoid leaks and explosions.
Green Hydrogen Fuel Can Solve More than Energy Problems
Hydrogen fuel is already available in nations such as Germany, France, the United States, Russia, and China. Moreover, Japan is going even further, aiming to develop a hydrogen economy. As green hydrogen becomes more common, there are several applications where it will be particularly useful.
For example, hydrogen fuel cells can produce drinkable water and electricity simultaneously. This phenomenon is a natural result of the reactions between oxygen and hydrogen within the cell. It has already seen practical employment in space missions, giving astronauts a sustainable power and water source.
In addition, the versatility of green hydrogen makes it a prime candidate for use in industries that have proven challenging to decarbonize. Foremost among these are aviation, heavy transportation, and marine transportation. The EU has already sponsored several projects like Cryoplane and Hycarus and has begun looking to employ them in passenger aircraft.
Finally, hydrogen has an excellent shelf life and several modes of storage. Hydrogen tanks are much lighter than lithium-ion batteries and can be easier to handle and transport. Furthermore, parts of our existing infrastructure can accommodate hydrogen fuel, whereas a complete electrical conversion may not be as efficient in time or money.
Green Hydrogen May Be the Best Fuel for Decarbonizing Our Industrial Base
As our energy needs rise to keep pace with the population, there are many different sources of power we ought to consider. Hydrogen is an abundant element, and (most importantly) it can burn clean. Furthermore, attaching hydrogen production to renewable power makes the entire life cycle of hydrogen green, allowing it to decarbonize sectors that have been difficult to address. Although there are several impediments to hydrogen use, such as safety and cost, it is poised to become an integral part of our sustainable energy system.
- Embrace Renewable – Hydrogen can be green or grey depending on the energy source for electrolysis. Likewise, your domestic power source can help or hinder the push for sustainability. Consider exploring greener options than oil or LNG to power your home.
- Save Water – Electrolysis produces pure water in addition to hydrogen. You can do your part to help conserve the water supply by using greywater to irrigate a flower garden and avoiding artificial fertilizers that pollute the water table with runoff.
- Stay Up-to-Date – Every fuel source is potentially flammable, not just hydrogen. So ensure your home and office boilers are inspected and serviced according to the manufacturer's recommendations.