Trelleborg explains why is it only now being considered as a fundamental part of a more sustainable world.
Currently, around 51% of the hydrogen that is used in the global economy goes to refineries, and 43% as an input for ammonia synthesis, primarily in the production of fertilizers. The most common process for producing hydrogen is steam methane reforming (SMR). This is fossil fuel-based and consumes around 6% of the world’s natural gas and 2% of its coal.
Hydrogen is rarely available in its pure form on Earth, so it requires extraction from compounds in which it is present. Any compound with ‘H’ in its chemical formula has hydrogen as one of its constituents, such as hydrocarbons, methane (CH4) and water (H2O). In fact, hydrogen makes up about 75% of the universe.
Although hydrogen is colourless, its different types are defined through a palette of colours that range from black (which comes from coal), pink (from nuclear), and turquoise (produced by pyrolysis of methane) to blue hydrogen (produced from natural gas with carbon capture technology), and what is currently the most common form, grey (extracted from coal gas). It is the source material and the production method that determine the extent to which the type of hydrogen is environmentally friendly.
So, if hydrogen derives from fossil fuels, why is it being seen as such an important part of a sustainable future? The holy grail is completely carbon-neutral or ‘green’ hydrogen.
Green hydrogen is made by passing water through an electrolysis cell powered by electricity generated from a renewable source, such as wind, solar or hydropower. The electricity divides hydrogen from oxygen, creating hydrogen gas at one electrode and oxygen at the other. The potential of green hydrogen in the sustainable energy mix lies in the fact that it can be burned in much the same way as natural gas is burned; and it can be run through a fuel cell, where it behaves in a similar way to a battery.
Though it has many uses, what has limited hydrogen’s applications so far is its energy-intensive extraction process, which sometimes uses more energy than the energy that is produced. Fossil fuel-based grey hydrogen is relatively cheap; up until now, the greener the hydrogen, the more costly it is to produce. However, this is changing as the production of green hydrogen becomes a more viable option and to some extent, an essential one.
Fossil fuels are becoming more and more expensive and increasingly unacceptable due to their impact on climate change. They are also being used as a bargaining tool in geopolitical conflicts, so the push for a reduction in dependence on these fuels is becoming more urgent by the day. There is also pressure on governments, global bodies, and industry to slash greenhouse gases to meet the zero emissions targets they have set. Realistically, these are only achievable through substantial new solutions, such as green hydrogen.
In addition, initiatives like the United Nations Green Catapult, the U.S. Department of Energy Hydrogen Program, China’s longterm hydrogen plan and legislative proposals from the European Commission are all leading to hydrogen extraction becoming prioritized, more efficient, and thus more cost-effective. Meanwhile, the falling costs of the production of solar and wind energy are significantly lowering the total costs of green hydrogen manufacturing.
Manufacturers will definitely be ‘greening’ the critical chemical processing applications that currently dominate hydrogen use. There will be a shift from grey to green hydrogen for fertilizer production, for instance. What about hydrogen cars? In fact, the first four-wheel vehicle powered by hydrogen and oxygen was conceived as long ago as 1807. Even back in the 1970s and 1980s, many saw hydrogen as the answer to the quest for green automobiles. Jack Nicholson, the Hollywood actor, wowed onlookers in 1978 with a car fueled by what today we would call ‘green hydrogen’.
In the intervening period, battery technology has improved dramatically so that battery electric vehicles (BEVs) now rival traditional powertrains in terms of range — the distance travelled on one charge at an electric point or after filling up at a gas station. Most experts agree that batteries rather than hydrogen fuel cells have won the race for sustainable car technology, although Honda became one of the first original equipment manufacturers (OEMs) to offer a hydrogen fuel-cell electric vehicle (FCEV) to retail customers, in 2008.
For other types of vehicles though, batteries have their limitations and hydrogen could be a better option. According to SAE International, OEMs and global suppliers are looking to hydrogen propulsion as a solution for decarbonizing heavy transport. However, hydrogen has been long the poor relation of the BEV, and it was only in 2020 that Hyundai began producing its Xcient hydrogen-fueled truck.
It’s therefore unsurprising that, until now there has been limited uptake and acceptance of hydrogen vehicles. According to Information Trends, only 56,000 hydrogenpowered vehicles are on the world’s roads in 2023, and very few of those are commercial or heavy-duty trucks. However, current breakthroughs in hydrogen technology could reduce fleet emissions while still providing reliable service with similar uptime to modern diesel trucks.
OEMs are focusing on developing the technology for difficult-to-electrify applications: for trucks that travel 400 kilometers or more daily and are being used in areas where the ambient air quality is low, or which have high duty-cycle applications (continuously in use for much of the day).
As a first step, most OEMs are concentrating on hydrogen-powered engines that utilize current technology and chassis. However, FCEVs could eventually provide a longterm solution to decarbonizing long haulage trucking. Hydrogen fuel cells offer great promise for heavyduty trucks in applications requiring a higher density of energy, fast refueling and additional range.
Beyond this there are also pressures on the shipping industry to lower its carbon footprint. Ships currently emit 3% of the world’s greenhouse gases. Several projects are underway, testing how hydrogen and other fuels made from it, such as ammonia and methanol, could power a low-carbon maritime industry.
Another area of interest is long-distance rail, and here technology is already a reality. Alstom’s Coradia iLint™ is the world’s first passenger train powered by a hydrogen fuel cell; in September 2022 it reached a new world record distance of 1,175 kilometers on a single filling.
The most significant sustainable application for hydrogen is its potential role in the stabilization of the electricity grid. This is because hydrogen is produced from electricity, is storable and has the capability to be converted back to electricity.
Renewable energy is inherently intermittent as it is dependent on when the sun shines or the wind blows. Although the efficiency of solar panels and turbines keeps increasing, there is a need for an alternative source when there is no energy generated. Currently, coal gas is the back-up and that is unsustainable due to its climate impact.
The panacea is filling that gap with green hydrogen. When there is peak production for wind and solar, turbines and panels produce more energy than is needed for the electricity grids they supply, so they shut down. That results in a loss of up to 20% of renewable energy’s capacity.
Major investment now focuses on integrating hydrogen with renewables. Instead of switching off panels and turbines at peak production times, the excess electricity would divert to produce green hydrogen, which goes into storage facilities. When the grid needs energy, the hydrogen would be converted back to electricity. Source