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Hydrogen, the holy grail of the energy transition?





Written by Jeroen Eblé, edited by Tessa Weersma & Denise De Cleene


Hydrogen, the most abundant element in the universe, is increasingly regarded as one of the key players in a future sustainable energy system. Some even go so far as to call it “the holy grail” of the energy transition. Whether they are right remains to be seen, but hydrogen does indeed boast interesting properties that are worth exploring. Let us go through them together and see how hydrogen can be positioned in the current energy transition.



What is hydrogen


How is hydrogen related to the energy transition?

One of the biggest challenges that humanity is currently facing is the energy transition that is necessary to combat climate change. Our current energy system runs largely on fossil fuels, a natural but finite source of energy, which emit vast amounts of CO2 causing harm to people and planet like climate change and global warming. To limit the consumption of fossil fuels (and its emissions), we must switch to an energy system that runs predominantly on renewables such as wind and solar power.


However, these forms of energy are not completely flawless yet. One of the main rules for energy systems is that supply and demand remain balanced – overproduction will result in a waste of energy and overdemand will result in unhappy customers. When it comes to wind and solar power, the supply cannot be controlled. And seeing that electricity can only be used at the time of production, this may result in a mismatch between production and consumption.


Mismatches occur in the short term, but also in the longer term. In this case, we often speak of seasonal mismatches. In the Netherlands for example, about 75% of the total yearly solar electricity is produced during six summer months, compared to only 25% during winter. Knowing that our energy consumption is significantly higher during winter (think of heating and lighting), this further distorts the balance in consumption and production of renewable electricity. Add to this that the share of renewable energy is only increasing, we can only see this mismatch widening.


This finding poses a challenge to our society as we must learn to capture the surplus of energy and put it to use according to demand. One of the best-known methods for this is battery energy storage, which is very suitable for short term mismatches. Unfortunately, however, batteries are not yet able to store energy in the long term and to such a large extent.


Figure 1: Electrolysis Process

Hydrogen is a chemical element which under normal conditions is a gas. It is very similar to natural gas and can be used for similar applications, except that it emits water instead of CO2 when used. Hydrogen is produced through electrolysis, a process whereby electricity is used to convert water into gas (oxygen and hydrogen). From that stage on, hydrogen is seen as an energy carrier, much like a battery. And when renewable electricity is used, it can be a completely carbon free energy carrier.


Compared to batteries, hydrogen allows for easier storage of seasonal mismatches, which means it will be very useful in conjunction with, and to stimulate the increase in, renewable electricity sources. But besides energy storage, hydrogen can be used for many other applications in different sectors. If we succeed in facilitating the production and distribution of hydrogen, it holds great potential for the future.


What was the role of hydrogen before?

When we go back in time, hydrogen has actually long played a role in the energy system. From the 19th century, “town gas”, which could contain about 50% hydrogen, was a common energy carrier produced from coal. Fast forward to the 21st century, where hydrogen is still widely used in the chemical industry for refining crude oil and producing ammonia (fertiliser) and methanol.


The hydrogen used in these processes is produced almost entirely from methane (the main component of natural gas), in a process called “steam methane reforming”, where methane is reformed into, mainly, CO2 and hydrogen. Currently, the CO2 is emitted into the atmosphere and the hydrogen produced is called grey hydrogen.


In the EU, approximately 340 TWh of hydrogen is produced in this way every year. It is important to note that the current use of hydrogen is fairly centralised: about 1/3 of it is consumed around Rotterdam, Antwerp, Chemelot and the Ruhr area. The production of this hydrogen led to the emission of 100 million tonnes of CO2, or roughly 50% of the Netherlands’ total emissions in 2017.


These hefty figures indicate that the market is already far from non-existent.


Potential applications of hydrogen


The number of potential applications of hydrogen is enormous. In general, the uses can be divided into the following categories:

  • Feedstock: replacement of already existing hydrogen feedstocks for ammonia fertiliser, methanol, and oil refineries. The use of hydrogen for feedstock can be extended to sustainable steel production and the synthesis of so-called e-fuels. E-fuels are electrochemically produced carbon-neutral fuels, used as an alternative to fuels like diesel and methane.

  • Electricity: hydrogen can be converted directly into electricity via a unit called a fuel cell. This application allows hydrogen to be used in the mobility sector in Fuel-Cell Electric Vehicles (FCEVs), both for consumer cars and for heavy transport. But fuel cells also make it possible to use hydrogen as an alternative form of general electricity generation, for example to power an island that is not connected to the electricity grid of its mainland.

  • Combustion: hydrogen is a highly flammable substance. Therefore, there are numerous applications for heat production, including in homes, but more particularly for high-temperature industrial heat. For internal combustion, hydrogen can be used in both reciprocating engines and turbines.


Figure 2: Simplified scheme of hydrogen production and applications

Production of hydrogen


So far, the future for hydrogen looks very bright. So, where is the catch? The main issue is that most of the processes for which we want to use hydrogen are currently based on fossil fuels. Fossil fuels have long spoiled us as a society by giving us enormous amounts of cheap energy. So much so, that the current share of renewable electricity production still seems peanuts in comparison. However, the transition is needed to save our planet.


Going forward, to truly unlock the future potential of hydrogen, the production must become less grey. There are several options for this, each with its own corresponding colour. Currently the main ones are:


  • Blue hydrogen, where the hydrogen is produced in the same way as the grey version, only the emitted CO2 will be captured and stored or utilized in a separate process.

  • Green hydrogen, where the hydrogen is produced using renewable electricity through a device called an Electrolyser, which splits water (H2O) into hydrogen (H2) and oxygen (O2).


In order to convert the energy consumed for all the above processes into green hydrogen, society will need a lot of renewable electricity. The shortage of energy content of renewable electricity compared to fossil fuels is compounded by the fact that during the process of production and storage of hydrogen, about 30% of the renewable electricity input to this process will be lost. This makes the production of green hydrogen rather expensive. Even blue hydrogen is quite expensive, as there is no carbon capture infrastructure yet.


How will hydrogen be applied in the future?


Mainly for economic reasons, it is unlikely that all the previously mentioned applications will run on hydrogen in the near future. However, we will soon see an introduction of hydrogen in so-called “hard-to-abate sectors”. These are the sectors where direct electrification is not, or not the best, option. For example, when only electricity is used, it is rather difficult to reach the temperatures required for some industries. In addition, shipping is also among the hard-to-abate sectors, where recharging the battery of a large vessel simply takes too long to be functional in the current transport system.


For processes where hydrogen is already used - in oil refineries and for the production of methanol and ammonia - it will probably first converted to a sustainable form of hydrogen. Subsequently, it makes sense to build and convert steel production plants to use hydrogen instead of the current fossil fuels.

Another possible option for using hydrogen may be high-temperature heat, as currently electric options do not seem capable of reaching sufficiently high temperatures.


After feedstock, next up will probably be the heavyduty transport sector, where the use of batteries will probably not be a viable option for some applications, such as shipping, aviation and possibly even trucks and buses.


Besides, there are still a lot of applications for which a (partial) transition to hydrogen is possible. However, this is difficult to predict at this point in time, as it depends heavily on other variables such as technical progress of batteries, but also on our ability to install sufficient renewable electricity production capacity.


To keep in mind


Imports of hydrogen

Since a great deal of renewable electricity is needed to produce hydrogen to meet demand, and since some European countries are already struggling to generate enough renewable electricity to even cover their electricity consumption, it is very likely that significant quantities of hydrogen will have to be imported from regions where a surplus of renewable electricity is easier to find. The need to import hydrogen most likely includes countries such as Belgium and the Netherlands, but also Germany and even France, regardless of plans to produce hydrogen from nuclear power.


Examples of locations likely to export large quantities of hydrogen include the Sahara Desert, the Middle East, some deserts in South America and Australia. In order to create an efficient and fair market for hydrogen trade, a new exchange should be developed, similar to the current one for natural gas.


Hydrogen carriers

Earlier in this article it was mentioned that hydrogen is used to produce several other substances, like ammonia, methanol, and the so-called e-fuels. Especially for long-distance transmission of hydrogen, it may be more efficient to convert the hydrogen into some other carrier, for instance methanol, than to transport the pure hydrogen itself. This is due to the fact that pure hydrogen must either be pressurised or liquified to bring its energy content up to the level of, say, gasoline. Both processes require so much additional energy that transport in the form of another substance becomes more efficient in some cases.


It is not yet entirely clear what the most efficient hydrogen carrier will be. Other concepts, like Liquid Organic Hydrogen Carriers (LOHC), are still under development and some are rapidly moving up the TRL ladder. Variables such as transport distance and final application are likely to determine the best option, along with which conversion techniques will provide major improvements. The main conclusion, however, is that even if the energy carrier is methanol, ammonia or LOHC, hydrogen is still the most important energy building block.


Conclusion


It is difficult to say exactly what the role of hydrogen will be in tomorrow's energy system, but as some very important sectors cannot be decarbonised with electricity alone, hydrogen will be needed in the future. Moreover, today's society is built entirely on fossil fuels, a form of energy that can be stored quite easily and does not need to be consumed at the moment it is produced or mined. Unfortunately, the same cannot be said for electricity. Direct electrification is always the better option, if possible. But because transport, industry and society as a whole are built on a very different kind of energy, it might prove very difficult to completely convert everything to run on electricity alone.


So, is hydrogen the holy grail of the energy transition? Probably not. Will it make a significant contribution to a more sustainable energy system? And will its use increase dramatically in the coming decades? Most probably yes.


How can we help?


Greenfish understands that no energy problem exists in isolation, as each problem is part of an integrated energy system. Other technical disciplines related to, for example, thermal and electrical challenges must also be taken into account. And as hydrogen is the embodiment of an integrator of energy sectors, we take a systems approach, considering different forms of production, consumption and infrastructure to ensure that the positive impact is not seen only at one end of the value chain.


This approach makes Greenfish well suited to guide the process of implementing green hydrogen-based solutions for our customers.



Interested to learn more? Get in touch with our energy experts.


Jeroen Eblé, Consultant & Hydrogen Expert Group Lead: jeble@greenfish.eu

Hugo Schoenmaker, Business Manager Energy: hschoenmaker@greenfish.eu

Mick Richards, Manager Energy Strategy: mrichards@greenfish.eu

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