GREEN HYDROGEN PRODUCTION AND ELECTROLYSIS; OVERVIEW, ADVANCEMENTS AND CONSIDERATIONS

According to Statista, the global market value for green hydrogen stood at $2.14 billion in 2021 and is expected to rise to over $135 billion by 2031. Forecasts also show that the global green energy market is expected to rise to $84.03 billion by 2029 from $6.42 billion in 2023. It's worth noting that these statistical projections would not exist without the obvious benefit of using green hydrogen.

Thanks to advancements in electrolysis, green hydrogen production technologies have gained popularity and resulted in economic growth. This article examines these advancements and their benefits to a world needing improved energy solutions.

Understanding Green Hydrogen and Electrolysis

By definition, green hydrogen is produced by water electrolysis using renewable electricity. Its production produces significantly fewer greenhouse emissions than grey hydrogen from fossil fuels without carbon capture. Green hydrogen can also be used to decarbonize sectors that are hard to electrify, such as heavy-duty transport, shipping, and aviation.

Green hydrogen can be applied in numerous ways. For instance, it can also store excess renewable energy, which can be converted back into electricity, thus balancing supply and demand. From an industry standpoint, green hydrogen can be applied in the following ways:

●????? Transportation: Green hydrogen can be used in fuel cells to power vehicles, emitting only heat and water vapor as byproducts. It is also perfect for buses and trucks where battery solutions might be impracticable due to weight and range limits.

●????? Shipping and Aviation: Hydrogen and hydrogen-derived fuels such as ammonia can power ships and reduce sulfur oxide and CO2 emissions. In aviation, hydrogen can be used in fuel cells or as a basis for synthetic fuels, assisting in the reduction of carbonized air travel.

●????? Public and Commercial Buildings: Hydrogen fuel cells offer reliable backup power for crucial infrastructure such as data centers, hospitals, and telecom towers. Hydrogen combined heat and power (CHP) systems can generate electricity and useful heat for buildings, increasing energy efficiency.

How Does Electrolysis Work?

Electrolysis is a process that uses electrical energy to create a non-spontaneous chemical reaction. Concerning green hydrogen production, electrolysis involves splitting water (H20) into hydrogen (H2) and oxygen (O2) using electricity obtained from renewable sources. There are different types of electrolysis technologies, including:

Alkaline Electrolyzers

Alkaline electrolyzers generate hydrogen using an alkaline solution, typically potassium hydroxide (KOH) or sodium hydroxide (NaOH), as the electrolyte. Water splits into hydrogen and oxygen at the electrodes. These electrolyzers are known for their simplicity, robustness, and cost-effectiveness, making them a mature technology for hydrogen production.

Proton Exchange Membrane (PEM) Electrolyzers

PEM electrolyzers provide high efficiency and function at higher current densities. They are also more flexible about rapid response to fluctuating power inputs, making them ideal for integration with renewable energy sources such as wind and solar.

Solid Oxide Electrolyzers

Solid oxide electrolyzers are perfect for utilizing waste heat from industrial processes. This has led to their widespread integration with industries requiring high temperatures. Their applications include large-scale hydrogen production, promoting industrial energy efficiency, and maximizing renewable energy for power and heat.

Recent Advancements in Electrolysis Technology

There have been various advancements in electrolysis technology that have improved green hydrogen production. These include:

Advances In Materials And Catalysts That Increase Efficiency

Nanotechnology is being used to create nanostructured electrodes, which improve the interaction between the electrode and the electrolyte. Porous electrodes are also more effective because they have a higher surface area and better gas diffusion, improving the electrolysis process's efficiency.

Advances in catalysts produced from non-precious metals, such as nickel, iron, and cobalt, have shown promise in achieving high efficiency while being more abundant and cost-effective.

Cost Reductions

Technological innovations such as improved and less expensive, non-precious metal catalysts reduce dependence on costly materials such as iridium and platinum. High-temperature electrolyzers such as solid oxide electrolyzers (SOEs) function at high temperatures, which can increase efficiency and reduce electricity costs.

From an economic perspective, scaling up the manufacturing of electrolyzers results in economies of scale and reduces the cost per unit. Larger production volumes also lower manufacturing costs through efficient production processes and the bulk purchase of materials.

There have also been energy efficiency improvements, as the increased efficiency of electrolyzers reduces the amount of electricity needed to produce hydrogen. This cuts operational costs since electricity is a major component of overall costs.

Innovations In Electrolyzer Designs

Developing enhanced proton exchange membranes (PEMs) with higher conductivity and durability increases the life span of PEM electrolyzers. Innovations such as novel polymers and composite materials can achieve this.

Creating bipolar plates with advanced materials, such as coated metals, can reduce weight and improve corrosion resistance, enhancing the performance and durability of electrolyzers.

Considerations

Green hydrogen production is an area of energy sustainability worth developing to new energy heights. However, there are multiple considerations, including:

Regulatory and Standardization Issues

Creating a clear and comprehensive regulatory framework, including permitting processes, safety standards, and environmental regulations, is crucial for safely storing and transporting hydrogen.

Technological Challenges

Hydrogen has a low energy density by volume,meaning it is to store and transport efficiently. Compressed and liquefied hydrogen are common solutions requiring significant energy input and advanced technology.

Hydrogen can also make metals brittle, resulting in possible leaks and failures in storage tanks and pipelines.

Transportation Issues

Establishing a pipeline network for hydrogen transportation is expensive and requires addressing material compatibility to prevent leaks and embrittlement.

Hydrogen can be shipped as a liquid or converted to ammonia for international transportation. However, these methods require additional complex conversion processes, which lead to higher costs.

Economic Considerations

Building and maintaining hydrogen storage and transportation infrastructure requires substantial investment. This includes pipelines, compressors, liquefaction plants, and specialized transport vehicles.

Infrastructure Development

Leveraging and improving existing natural gas infrastructure for hydrogen use can reduce costs, but it requires careful consideration of compatibility and safety issues.

Conclusion

Green hydrogen provides numerous energy benefits, from fuel cell technology for vehicles and portable power systems to promoting energy independence from fossil fuels. With the right structures, Nigeria can adequately tap into this power source and resolve energy issues that have persistently plagued the nation.