When you hear of Hydrogen, what is the first thing that strikes your mind? If you’re thinking it’s the lightest element on the planet, then you’d be right.
However, can Hydrogen also become known as the fuel of the future? According to recent studies, a kilogram of hydrogen has about three times as much energy as a comparable amount of diesel or gasoline.
It’s worth noting that there is more hydrogen in the universe than any other element (approximately 90% of all atoms are hydrogen). In fact, you can get hydrogen from the most abundant resource found in nature: water or H2O.
No wonder so many countries and government officials are investing millions of dollars into researching the development of hydrogen and fuel cells.
What is green hydrogen and how do you make it?
In simple words, Green Hydrogen is produced from using renewable energy instead of fossil fuels. To produce green hydrogen, you need water, a big electrolyzer, and a plentiful supply of electricity.
The ability to produce large amounts of green hydrogen will play a crucial role in providing an alternative to fossil fuels as we transition to low emissions and work towards a clean, healthy environment.
Hydrogen, as an energy carrier, is versatile, as it can be used in gas or liquid form, be converted into electricity or fuel, and there are many ways of producing it.
Approximately 70 million metric tons of hydrogen are already produced globally every year for use in oil refining, ammonia production, steel manufacturing, chemical and fertilizer production, food processing, metallurgy, and more.
The problem here is that we are talking about “dirty” or “grey” hydrogen – as producing it needs lots of (usually coal fired) electricity.
What are the advantages of transitioning to Green Hydrogen?
Green Hydrogen can supply up to 25% of the world’s energy needs by 2050. Australia, Chile, Germany, Japan, New Zealand, Saudi Arabia are a few to have published hydrogen strategies.
Let’s look at the advantages of green hydrogen:
Green hydrogen does not emit polluting gases either during combustion or during production. It is friendly toward the environment and doesn’t cause any harm or destruction to human health.
It has the potential to provide clean power for manufacturing, transportation, and more — and turning it’s only byproduct when turning it back into energy is water. It’s energy density is quite high (ammonia has a similar energy density as coal).
So this seems to be a perfect carrier of excess renewable energy when there is more wind or sun being turned into green energy than the network can take.
Green hydrogen can be transformed into electricity or synthetic gas and used for domestic, commercial, industrial or mobility purposes.
It can be mixed with natural gas at ratios of up to 20% and travel through the same gas pipes and infrastructure – increasing this percentage would require changing different elements in the existing gas networks to make them compatible.
What are its challenges?
The issue with hydrogen is that its highly flammable and its light, therefore transporting and storing is not easy.
Compared to gasoline, natural gas, and propane, hydrogen is more flammable in the air. Since hydrogen is so much less dense than gasoline, it is also difficult to transport.
It either needs to be cooled to -253˚C to liquefy it, or it needs to be compressed to 700 times atmospheric pressure so it can be delivered as a compressed gas.
One way around that could be producing green ammonia – which takes more energy and nitrogen from the air to produce. Even though it’s energy balance is less appealing than pure hydrogen, it is easier to transport and store (and apart from turning it into electricity it also has its traditional use in agriculture and industry).
It can be transported in common containers on (hopefully hydrogen powered) container ships around the world. Big energy utilities in Europe are already looking into that as an option by securing supply from yet to be built green ammonia projects around the world.
For bulk transport, the supply of hydrogen requires dedicated pipelines, which are costly. For instance, natural gas pipelines (of which there are plenty) are sometimes used to transport only a limited amount of hydrogen because a high concentration of hydrogen can make steel pipes and welds brittle, causing cracks.
To reduce overall hydrogen cost, currently the research is focused on improving hydrogen production technologies, operations and maintenance.
Besides this, other factors to keep in mind are:
High in cost
Generating it through electrolysis is what makes hydrogen more expensive to obtain. Countries like Germany are putting some of their money towards research on bringing the cost of those electrolysers down as well.
High energy consumption
The production of hydrogen in general and green hydrogen in particular requires more energy than other fuels.
Hydrogen is a highly volatile and flammable element and thus extensive safety measures and precautions are required to prevent leakage and explosions.
How can green hydrogen be used?
Described by the International Energy Agency as a “versatile energy carrier,” hydrogen has a diverse range of applications and can be deployed in sectors such as industry and transport.
Electricity & Drinking Water Generator
Hydrogen-powered electricity turbines that can generate electricity during a high peak demand to help firm the electricity grid.
Compressed Green hydrogen tanks are capable of storing energy for long periods of time and are also easier to handle than lithium-ion batteries because they are lighter.
Transport & Mobility
Green hydrogen is a great suited for heavy transport that is difficult to decarbonise, such as aviation and maritime transport. Also, ideal for electric cars.
A substitute for natural gas for cooking and heating in home.
Burning hydrogen as a heat instead of coal.
What is green hydrogen’s future?
Green hydrogen has a great potential because thanks to its versatility, it can be used in multiple sectors. Experts and scientists believe that there will be substantial use of green hydrogen over the next five to ten years, and thus, it is predicted that green hydrogen production is set to exceed $1 billion a year by 2023.
Ultimately, whether or not green hydrogen fulfills its promise and potential depends on how much car manufacturers, fueling station developers, energy companies, and governments are willing to invest in it over the next number of years.
Doing nothing about global warming is not an option which is where green hydrogen, despite its drawbacks with infrastructure and economics, has a great deal of potential.