Hydrogen: small but powerful

Hydrogen gets the green light

Hydrogen is often described as a clean, flexible energy carrier for the future. But how can it fulfill that promise? In the first article in our two-part series, we discussed ways of hydrogen production and some of the basics of hydrogen as an energy carrier. Now, in part two, we’ll focus on hydrogen use cases in various industries and how hydrogen can make the grid more stable.

Due to its high versatility, hydrogen has the potential to become one of the key drivers of decarbonization, but there has to be a strategic approach to how or when it can be used. If there are cheaper sources or technologies available that are suitable for a particular sector, there is no reason why those shouldn’t be favoured. Also, you must consider whether the existing infrastructure lends itself to hydrogen solutions, as well as establish the necessary regulatory frameworks.

As hydrogen is quite expensive to transport and store, it should be applied at a scale where there are no other viable decarbonization alternatives: industry, transport, buildings, and power.

A jack of all trades

Since hydrogen reacts with most elements, it is used in many industries for the production of various materials. Electronic components, rocket fuel, ammonia for fertilizers, textile fibers, glass for flat screens, mechanical parts in metallurgy - it’s a long list, which shows that there is a huge demand for hydrogen in industrial processes, especially in heavy industry. Chemicals, refining, and iron and steel are the primary markets, and the only real challenge switching to low-carbon hydrogen presents is that right now the production of hydrogen isn’t advanced or sustainable enough.

Whether it’s by land, sea, or air, heavy transportation is responsible for a large amount of carbon emissions. Hydrogen-based synthetic fuels in air and sea transport are unlikely to become widely used in this decade, but in the long run, they could replace gas or diesel in aviation and ocean shipping, i.e., applications that cause high emissions. Advanced biofuels, such as fuels from algae or waste, might compete with synthetic fuels in the future, but their commercial development is still in its infancy. Even though low-carbon hydrogen is still expensive and there are not enough hydrogen fueling stations available, it has enormous potential in road transport when combined with fuel cells in zero-emission electric vehicles: a fuel cell is two to three times more efficient than a conventional internal combustion engine that runs on gas.

Hydrogen-based technologies might play a key role in powering buildings, too. To ensure that the number of buildings with a low heating demand increases, we need to determine the ideal technology for heating (and cooling) while taking the upgrade costs into account. A hydrogen boiler solution is a smart choice since it can reuse existing infrastructure - the importance of such solutions in the residential sector is likely to increase in the coming years.

The image below shows how hydrogen is used globally.

… and a master of flexibility

Given that commonly used storage solutions, such as batteries or pumped-storage hydroelectricity, cannot really address the challenges the intermittent nature of solar and wind energy presents-batteries can only store energy for a limited amount of time, while pumped-storage hydroelectricity is costly and geographically limited-  we need innovative solutions that can balance grid supply and guarantee long-term energy storage. While air-source heat pumps using renewable electricity are quite energy-efficient and cost-effective, the versatility of hydrogen offers many alternatives, such as hydrogen boilers, hydrogen fuel cells, and heat pumps - both with an auxiliary hydrogen boiler - or renewable electrolysis hydrogen. This last technology is commonly referred to as power-to-gas (P2G) and involves converting surplus renewable energy into hydrogen gas through electrolysis. The gas can then be injected into the grid and reduce emissions by replacing natural gas, resulting in a greener gas mix. By converting hydrogen to energy carriers that are easy to store, P2G can make a significant contribution to long-term energy storage, while resulting in the reduction of the grid load, i.e., flexible demand. 

System flexibility is further boosted through sector coupling, which refers to the close integration of large energy consumers, such as the three we discussed above, with power production. While the energy transition initially emphasized the use of renewables to decarbonize electricity, sector coupling supports the decarbonization of these additional sectors through electrification and shifts their primary energy source to renewables. When coupled to a power grid, hydrogen technology becomes a component of the system, adding flexibility to it. Just like electric vehicles or heat pumps, electrolyzers for hydrogen production can be integrated into the grid. Also, coupling the power and the hydrogen sectors supports the integration of variable renewable energy in the former and lead to system cost reductions.

The diagram below shows how hydrogen fits into sector coupling.

Since it can be generated from renewable power, and then used directly for heating, transport or industry, or even to generate power at a later time, hydrogen holds enormous promise. However, it is essential to reduce the costs of related technologies and of hydrogen’s derivative synthetic fuels. Additionally, markets, where there is demand for such fuels, need to develop at scale.

The momentum hydrogen is enjoying both in politics and in business keeps growing, and the industry should take advantage of it: if technologies are scaled up and costs lowered, hydrogen can become an important part of a clean and secure energy future. In fact, it is already an integral part of the European Union’s plan to achieve climate neutrality by 2050. The European Network of Transmission System Operators for Gas (ENTSOG) has set up a visualization platform where you can find all renewable and low-carbon hydrogen projects in Europe.

The view below shows hydrogen production projects.

Luckily, the rest of the world isn’t lagging too far behind.

Especially the use case of long-term storage can be a viable solution to shift excess renewable generation to a later point in time where it is of higher value and more favourable for the grid. Combined with the flexibility to decide when and how much hydrogen should be produced (demand-side flexibility) this is a very intriguing flexibility optimization task that requires deep understanding of both storage technologies and how their value can be maximised on short-term power markets.