What is the hydrogen economy?
The hydrogen economy encompasses the many systems required to ensure the sustainability of hydrogen as a fuel source. Here we discuss the current state of the hydrogen economy and the benefits presented by an established hydrogen infrastructure as well as the challenges that must still be overcome.
Current state of the hydrogen economy & projected trajectory
The idea of a hydrogen economy has been around since the 1970s, yet the high cost and lack of established infrastructure has left it on the backburner – until recently. A global push toward sustainable systems is rekindling interest in the concept of a hydrogen economy. In 2020, Europe took a huge step forward by spending in excess of €45 billion to establish hydrogen production from “greener” sources and to scale hydrogen distribution and fuel cell infrastructure – and it is projected that by 2050, €180-470 billion will be invested into renewable hydrogen.
Benefits of using hydrogen as a fuel source
Hydrogen has a lot to offer as an energy efficient, environmentally friendly alternative fuel source. Whereas hydrocarbon based fuels used to power combustion engines release harmful emissions into the air, hydrogen fuel can be used to power fuel cells – with water as the only byproduct!
Fuel cell equation: 2H2 + O2 -> 2H2O + Energy
Hydrogen can also be used synergistically with other renewable energy sources. Energy generated by solar and wind must be used immediately and relies on weather patterns, but hydrogen can be stored as a liquid or gas until it is needed and can be produced as long as supply permits. This makes the hydrogen economy an ideal bridge between renewable energy sources and our current energy demand.
Challenges faced by the developing hydrogen economy – and solutions
For the time being, the hydrogen economy lacks the economies of scale required for hydrogen and fuel cells to immediately replace fossil fuels and combustion engines – and getting to that point will require several initial investments in technology. As groups like the automotive industry continue R&D into fuel cell technology, more affordable and scalable solutions will become available.
Energy intensive hydrogen production
One hurdle for the hydrogen economy is optimizing the energy intensive electrolysis and water purification processes required to produce green hydrogen. Several industrial scale projects are working on providing the necessary solutions. One such solution is high temperature electrolysis, which can greatly improve electrolysis efficiency due to the added heat energy (although this can also induce electrolyzer lifetime limitations). Additionally, early research in photochemical, photobiological, and biomass methods present promising alternatives for green hydrogen production.
Lack of hydrogen electric vehicles & fueling stations
Hydrogen powered vehicles present numerous benefits over combustion engines and battery-powered vehicles, offering carbon neutrality, greater driving ranges, and reduced fuel times all in one. But the automotive industry is facing a dilemma: there is a lack of hydrogen powered vehicles, partially due to lack of hydrogen fueling stations… and there is a lack of fueling stations, partially due to a lack of hydrogen vehicles. Fixing this dilemma is certainly not cheap, but the benefits are quite intriguing, and several government initiatives are working to accelerate the transition to an established hydrogen economy.
Need for better hydrogen storage and dispensing techniques
Storing and dispensing hydrogen is also a challenge for the hydrogen economy due to the extreme pressures and temperatures required to store pure hydrogen efficiently, but new technologies are being developed to overcome this. One such development is the use of metal oxides for storage – e.g. storing hydrogen as magnesium hydride paste.
Additionally, existing infrastructure for off-shore oil and gas can be repurposed with hydrogen generation and storage infrastructure, using oil rigs to mount electrolysis systems and depleted natural gas caverns and pipelines for hydrogen storage and transport.
The hydrogen economy will likely play a significant role in the decarbonization of our existing systems – and given the large allocation of funding and efforts into this infrastructure, this will hopefully become a reality within the next few years!