Beyond Oil and Gas - The Hydrogen Future

The world is currently experiencing a transition in energy sources. Fossil fuels, predominantly coal, oil, and natural gas, have been the world's primary energy sources over the last century. Now, more and more countries are looking toward renewable energy sources like wind, solar, geothermal, and hydropower. One of these emerging energy sources is hydrogen fuel, which is becoming increasingly popular due to its potential to reduce greenhouse gas emissions and provide a clean source of energy. As we explore the transition potential to hydrogen fuel and to the benefits of hydrogen as an energy source, it is clear there is lots of work to be done and significant opportunity for technological advancement. In addition to the high cost of production and limited infrastructure, there are also substantial technical requirements associated with using hydrogen fuel, particularly in the compression and storage of hydrogen gas.

What Is Hydrogen?

Hydrogen, in its simplest form, is a chemical element. Hydrogen is the first element on the periodic table. It is the lightest and most abundant element in the universe, representing roughly 75% of the known universes elemental mass. Hydrogen is a colorless, odorless, and tasteless gas at ambient temperature and atmospheric pressure and is highly flammable. When we use the term “Hydrogen Fuel.” we are referring to the use of hydrogen as a fuel source. This fueling can involve using hydrogen as a standalone fuel or as a feedstock to produce other forms of energy, such as synthetic fuels or electricity.

Fun Fact:  Did you know that hydro-gen in Greek translates to water-maker? 

One of the key advantages of hydrogen fuel is its environmental benefits. When hydrogen is burned, it produces only water and heat, making it a cleaner energy source. It can be produced from various sources, including natural gas, biomass, and water, using processes such as steam methane reforming, electrolysis, and photovoltaic cells. Hydrogen fuel cells convert hydrogen into electricity, making it an ideal energy source for transportation, power generation, and industrial processes. Hydrogen fuel cells also have high efficiency levels, making them a sustainable energy source. 

In transportation, hydrogen fuel cells are being produced as a source to power electric vehicles, providing a clean and efficient alternative to traditional combustion engines. Additionally, Hydrogen fuel cell technology is significantly more achievable than battery power for electric vehicles, as hydrogen is an abundant renewable resource and has considerably less environmental impact than resource mining required for battery production.

In power generation, hydrogen can be used to generate electricity through fuel cells, which can be harnessed to power homes and businesses. In industrial processes, hydrogen can be used as a feedstock to produce chemicals and materials, reducing reliance on traditional fuel sources. Industrial production is commonly found in the form of steam reforming of natural gas, oil reforming, or coal gasification. Most hydrogen is utilized near the site of its production, the two most prominent uses being fossil fuel processing (e.g., hydrocracking) and ammonia production for fertilizers. The reason for this speed-to-use is due to the current difficulty to transport hydrogen long distances and the reduced economic impact of producing hydrogen at or near its use site.

What are the challenges on the road ahead?

Some challenges are on the horizon associated with this transition to hydrogen fuel. One of the primary challenges is the cost of producing hydrogen. Currently, hydrogen production is more expensive than traditional fuel sources due to the relatively small infrastructure developed around supporting this emerging market. However, as the technology for producing hydrogen improves and the demand for hydrogen increases, the cost of producing hydrogen is expected to decrease. Another challenge is the infrastructure required to support the transition to hydrogen fuel. This includes the production, storage, and transportation of hydrogen, and the installation of fueling stations for hydrogen-powered vehicles. This infrastructure is currently limited, but efforts are underway to expand it to support the growing demand for hydrogen fuel.

Compression is one of the primary technical requirements for using hydrogen fuel. Hydrogen gas has a low density, meaning it takes up a lot of space in its natural form. To be used in transportation or other applications, the gas must be compressed to increase its density and reduce the space it occupies. The compression process is typically achieved using diaphragm or reciprocating compressors, which can compress the gas to pressures of up to 10,000 psi. Some compressor manufacturers are exploring increasing this discharge pressure to upwards of 15,000 psi. 

This presents significant technical challenges as new materials must be developed to achieve these demanding pressures. The materials used in the compression system must withstand these high pressures while ensuring the gas is contained safely. The compression process requires high-strength polymer materials.  In some cases, the process necessitates the development of currently unproduced polymers resistant to hydrogen embrittlement, a phenomenon in which hydrogen gas can cause materials to become brittle and crack.

Another challenge associated with hydrogen fuel is the storage of the gas. Hydrogen is typically stored as a compressed gas, requiring high-pressure tanks to contain the gas safely. However, the high pressure and corrosive nature of hydrogen gas means that revolutionary containment designs, unique materials, and special coatings are required to prevent leakage and ensure the safety of the storage system. In addition to compressed gas storage, hydrogen can be stored as a liquid or a solid. Liquid hydrogen is stored at exceptionally low temperatures, typically below -253°C, and requires special cryogenic storage tanks and seals that can withstand these ultra-low temperatures.

On the other hand, solid hydrogen storage uses materials that can absorb and release hydrogen gas, such as metal hydrides, carbon nanotubes, or other advanced materials. The process for solid hydrogen storage varies depending on the specific material being used. However, in general, the process involves loading the material with hydrogen gas and then releasing it when needed. This can be achieved through a variety of mechanisms, such as heating the material to release the hydrogen gas, applying pressure to release the gas, or using a catalyst to facilitate the release of the gas. While solid hydrogen storage has the potential to offer advantages over compressed gas storage, such as lower pressure requirements and increased safety, it is still a developing technology, and there are challenges associated with its use. Some materials may have limited hydrogen storage capacity, and the gas release may require significant energy input to convert.

Material Advancements

The extreme requirements of materials and sealing technologies for hydrogen storage and transport are challenges our industry has never faced before. Common materials used today in the manufacturing of seals for the high-stress environments found in hydrogen compression and storage are polymer-based materials, such as polytetrafluoroethylene (PTFE) and polyetheretherketone (PEEK), as well as metal-based materials, such as aluminum, titanium, and stainless steel. These materials are selected for their high strength, resistance to hydrogen embrittlement, and compatibility with the high-pressure and corrosive environment of hydrogen gas. 

PTFE, for example, is a widely used polymer material for hydrogen compressor seals due to its high chemical resistance, low friction, and high-temperature tolerance. PTFE is often combined with other materials, such as carbon, graphite or glass fiber, to enhance its strength and wear resistance.

PEEK is another high-performance polymer sourced for hydrogen compressor seals due to its excellent mechanical properties, high-temperature resistance, and resistance to hydrogen embrittlement. PEEK can also be reinforced with glass or carbon fiber fillers to increase its strength and stiffness.

In addition to these traditional seal materials, advanced materials such as carbon fiber-reinforced polymer composites (CFRP), ceramic materials, and nanocomposites are being developed for hydrogen compression systems. These materials offer unique combinations of high strength, stiffness, and hydrogen permeation resistance, making them promising candidates for future hydrogen compressor seals. These extreme working environments continue to push the need to develop advanced technologies and materials that can withstand greater temperatures and pressures as we continue to expand hydrogen fuel. These include innovations in high-strength polymers and composites, such as carbon fiber-reinforced polymers. Other technologies, such as nanostructured materials, are constantly being developed to improve the safety and performance of hydrogen storage and transport systems.

Despite these technical challenges, hydrogen fuel offers significant environmental and economic benefits. It is rapidly gaining popularity as one of the front runners in the search for clean and sustainable energy sources. As the demand for hydrogen fuel grows, the development of new technologies and materials will continue to improve the safety and efficiency of hydrogen storage and transport, making it a promising energy source for the future.

The transition from traditional fuel sources to hydrogen fuel is not without its challenges, particularly in the compression and storage of the gas and the need for more advanced technologies and materials to perform in these demanding applications. As the world continues on the path of energy transition, seeking alternative fuel sources, hydrogen is positioned as a vital step in the shift towards a more sustainable and clean energy future.