Green Hydrogen

Hydrogen is the most abundant element in the universe and it is considered to represent the chemical "template" for every other atom. Not only is hydrogen a necessary component of our very existence, but it is often associated with energy production. Traditional sectors (such as the oil & gas industry) produce hydrogen as a byproduct of fossil fuels. This can result in damage to the environment. The good news is that an emerging technology referred to as "green hydrogen" could very well transform energy production as we know it.

There are nonetheless several topics to address if we hope to understand what green hydrogen technology may be able to offer. How do we define green hydrogen? How do green hydrogen systems function? Are there any specific benefits and possible drawbacks to address with green hydrogen? This article will take an objective look at green hydrogen so that the proper conclusions can be subsequently drawn.

What is Green Hydrogen?

There are many different ways in which hydrogen can be used as a means to produce energy. To be clear, we are not referring to the disparate isotopes in this sense. We are instead focusing around the applications of the gas itself. While most consumers are unaware of this fact, hydrogen-based sources of energy can be broken down into two categories^[1]:

• Blue hydrogen
• Green hydrogen

Blue hydrogen is essentially based on models that perpetuate the consumption of fossil fuels (such as oil and natural gas). The name is derived from the blue flame that is produced during the combustion process. The issue here is that these methods can still have a negative impact upon the environment thanks to the release of carbon dioxide into the atmosphere. Thus, companies are now researching ways to phase out blue hydrogen.

This is when the power of green hydrogen comes into play. Green hydrogen production is directly associated with the electrolysis of water. In this case, an electrical current is sent through a vessel of water. The water is then broken down into its constituent components (hydrogen and oxygen). The green hydrogen generated can either be used immediately or stored for future consumption. The same holds true in regards to oxygen. To put it simply, the electrolysis of water represents a pollutant-free process and it is therefore highly attractive.^[2]

How is Green Hydrogen Produced?

The exact process of producing green oxygen is likewise relatively straightforward. As mentioned in the previous section, this involves the electrolysis of water. Positive and negative terminals (known as the "anode" and the "cathode") are placed into a vessel of water referred to as an electrolyser. When a current is supplied, the atoms of water are "split" into hydrogen and oxygen. To observe & automate this process you could use a SCADA system.

However, it should be noted that the water will need to contain minerals and salts in order to conduct a current. This process is very difficult to achieve using pure water. Once green hydrogen and oxygen are generated, these two gases can be collected at the cathode and anode (respectively). They may then be directly used or stored for later purposes. From a technical perspective, this type of electrolysis to generate green hydrogen is known as an oxidation-reduction reaction.^[3]

What Advantages and Possible Drawbacks are Associated with Green Hydrogen?

We can already see that green H2 production is relatively straightforward from the point of view of a chemist or physicist. However, it is still important to highlight some of the primary benefits of green hydrogen before moving on to summarise a handful of possible pitfalls.

The Benefits of Green Hydrogen

From a macroscopic perspective, switching to a hydrogen-based economy could theoretically reduce global carbon dioxide production by as much as 99 percent. In terms of green hydrogen, it is also estimated that this technology may be able to reduce greenhouse gas emissions by 830 million tonnes on an annual basis.^[4] In other words, the large-scale deployment of green hydrogen could have an immensely positive impact upon the environment and help to address issues such as climate change.

Versatility is another distinct advantage attributed to green hydrogen. This arises from the ways in which it can be produced. Green hydrogen can either be stored in the form of a synthetic gas or converted directly into electricity via a generator. The same holds true in regard to the green hydrogen uses themselves. Some potential applications include^[5]:

• Industrial (for example for backup power supply).
• Domestic (fueling everyday appliances such as stoves and boilers)
• Traffic technologies (hydrogen fuel cells employed to power vehicles)

Efficiency is yet a final point to emphasise. As green hydrogen is extremely lightweight, it is easy to transport and thus, the associated consumer costs can be reduced over time. Green hydrogen is also capable of providing more energy per kilogramme when compared to fossil fuels and certain other alternative technologies.^[5]

Possible Disadvantages to Note

It is nonetheless prudent to take on the role of devil’s advocate before a moment before further examining green hydrogen. There are indeed some possible drawbacks that need to be mentioned. Perhaps the most logistically confounding problem is that at the moment, green hydrogen is still relatively expensive to produce on a large-scale basis. Thus, it might not represent as much of a viable solution when compared to standard forms of energy production.

Also, the electrolysis process requires a relatively large amount of energy to produce green hydrogen. This has caused some experts to question the economic benefits outlined in the prior section.^[6]

A final concern is that green hydrogen is a highly flammable gas. Storage could therefore present a problem; particularly to those who do not possess the proper level of training. It is therefore somewhat reasonable to appreciate why firms are rather hesitant to adopt green hydrogen in favour of tried-and-tested technologies.

Are There Alternatives to Green Hydrogen?

While it is indeed true that green hydrogen shows promise in terms of its potential to embrace a net-zero approach to emissions, scientists are still looking at possible alternatives until these systems become slightly more advanced. So, what options currently exist?

One solution that has already existed for some time comes in the form of solar power (photovoltaics). As energy is generated from the power of the sun, this option is also associated with a low carbon footprint. Solar cells have already enjoyed widespread use and the number of associated applications continues to increase.

Leveraging clean natural resources is another very real possibility that has already enjoyed widespread prevalence. Some examples of the ways in which the energy of the earth can be used to our advantage include^[7]:

• Geothermal power
• Wind turbines
• Wave energy

Having said this, there is little doubt that the techniques associated with the production of green hydrogen will continue to evolve. It is therefore perfectly reasonable to assume that this industry should enjoy a growing presence in the not-so-distant future.

What Does the Future of Green Hydrogen Have in Store?

Might the term "green hydrogen" one day become a household name? Considering the fact that green hydrogen is an extremely clean source of renewable energy, it could very well provide an alternative to fossil fuels. However, the cost of producing green hydrogen and its flammable nature will require innovative solutions if this technology hopes to further evolve.

It is still a fact that cutting-edge firms such as SFC have already leveraged hydrogen-based technology in order to provide their customers with innovative off-grid solutions and this is only the tip of the proverbial iceberg. While green hydrogen may still be in its infancy, the advantages attributed to hydrogen gas cannot be overstated.

Hydrogen fuel cells are now utilised to provide a redundant source of power, to ensure that electrical systems remain functional in the event that mains electricity is lost and these hydrogen fuel cells have become popular within vehicles. Logic alone dictates that green hydrogen should enjoy an increased market share thanks to these systems alone. Either way, there is little doubt that green hydrogen represents yet another means to offset the effects of climate change.