Everyone is talking about hydrogen at least since the national hydrogen strategy was adopted. Also at FfE, research is being conducted into the contribution of hydrogen to the future energy system. Current projects focus on the sustainable production, transport and use of hydrogen as well as on overarching issues of market development and business models.
This article is the third in a series of six articles that will be published successively in the coming weeks. In this series of articles, the most important aspects of hydrogen will be explained briefly, comprehensibly and compactly.
Overview of the topics in the series of articles on hydrogen
- History of hydrogen as an energy carrier
- How is hydrogen produced?
- Where will hydrogen be used?
- How is hydrogen transported?
- What contribution can hydrogen make to the energy transition?
- Overview of current hydrogen projects
This article explores the use of hydrogen, examining its current applications and future potential. Hydrogen can be used as both a material and an energy source. Currently, hydrogen is used predominantly for material purposes, with only minor applications in the steel industry. In the future, hydrogen could be employed in boilers, industrial furnaces, and, more rarely, fuel cells for generating heat and electricity. Additionally, hydrogen serves as a foundation for producing synthetic gaseous, liquid, and solid hydrocarbons. Some typical sectors and applications in which hydrogen could be used in large quantities today and in the future are presented below.
In current discussions, hydrogen’s energy applications, especially in the field of transportation and mobility, are frequently highlighted. However, only a fraction of 0.01 percent of the total global demand for hydrogen is currently used in the mobility sector. Material applications dominate the current demand for hydrogen. It is used in refineries for the production of conventional fuels on the one hand and in basic chemicals for the production of ammonia and methanol on the other.  Ammonia, for example, is processed into fertilizer and will continue to be needed in large quantities in the future. The total national hydrogen consumption in Germany currently amounts to around 55 TWh. These ‘gray’ hydrogen requirements – discussed in part 2 of this series – can already be substituted with climate-neutrally produced hydrogen today, without any technical process alterations, thereby reducing greenhouse gas emissions. 
Demand for hydrogen is likely to increase in the future, as it will enable a reduction in CO2 emissions in many sectors and applications that are difficult to decarbonize. Hydrogen plays a key role in sector coupling here. The German government expects demand to double to up to 110 TWh by 2030 . Studies project that, by 2050, the demand for hydrogen and its derivatives in Germany will typically range between 400 and 800 TWh. [3, 4] The likely “no-regret” applications in the near future in various sectors are discussed below. 
In the industrial sector, the demand for hydrogen is expected to be high in the future, particularly in steel production. Here, the process of direct reduction with hydrogen offers the potential to reduce CO2 emissions in the production of steel, which currently requires large quantities of coal in the blast furnace process and emits around 215 million tons of CO2 across Europe.  However, the production of steel using direct reduction requires new production facilities and, unlike in basic chemicals, cannot be decarbonized simply by changing the energy source or raw material. A Europe-wide switch to steel production using hydrogen would lead to a sharp increase in demand for hydrogen (288 TWh in 2050).  Another possible hydrogen application in the industrial sector is high-temperature processes, in which hydrogen burners could be used, but which compete with the direct electrification of the respective processes. For the entire industrial sector, including basic chemicals, studies indicate demand in Germany of up to 50 TWh in 2030 and up to 500 TWh in 2050. 
In addition to the industrial sector, the transport sector also has potential for high future demand for hydrogen. In international aviation and shipping, for example, the high energy densities required mean that electrochemical battery storage systems are often not a suitable technology for reducing greenhouse gas emissions. Here, synthetic green fuels derived from hydrogen are seen as a suitable alternative to fossil fuels thanks to their high energy density. These synthetic fuels derived from green hydrogen are often referred to as power-to-liquid (PtL) in the case of liquid fuels, while gaseous fuels are often referred to as power-to-gas (PtG).  These synthetic fuels have the disadvantage of significantly lower efficiencies compared to direct electrification. Hydrogen requirements for the entire transport sector in studies amount to up to 57 TWh in 2030 and fluctuate between 150 and 300 TWh in 2050, with requirements in aviation and shipping of 140 to 200 TWh. The fluctuations in demand are mainly the result of varying proportions of hydrogen fuel cell vehicles in road transportation. The alternative in the respective studies is the direct electrification of road transportation, i.e. the use of battery electric vehicles or electric rail-based transit. 
In the conversion sector, hydrogen enables seasonal energy storage. Hydrogen can be produced and stored from renewable energies using electrolysis. In times of low electricity supply from volatile renewable energy sources, this stored hydrogen can be converted back into electricity in gas turbines or fuel cells. In future, hydrogen could therefore be used to cover the residual peak load in the energy system. The demand in the conversion sector is still low in studies in 2030 at up to 20 TWh, but increases to 292 TWh in studies up to 2050. .
In addition to the applications presented, there are many other applications, such as in the building and heating sector, whose future use depends heavily on the cost of hydrogen and other factors, such as the renovation rate of existing buildings. Under current assumptions, alternatives such as heat pumps are often cheaper and more efficient for these applications.  
Hydrogen can therefore be used in a wide variety of ways, although in many sectors and applications it competes with alternative technologies that also enable a reduction in emissions. However, a significant increase in the overall demand for hydrogen is to be expected. As part of the Trans4ReaL transfer research project, FfE is supporting the real-world laboratories of the energy transition, in which various applications of hydrogen are being scientifically investigated on an industrial scale.
- Trans4ReaL – Transferforschung für die Reallabore der Energiewende zu Sektorkopplung und Wasserstoff
- Welche strombasierten Kraftstoffe sind im zukünftigen Energiesystem relevant?
- eXtremOS-Findings: How do extreme scenarios affect the European energy system
 International Energy Agency – IEA (2019) The Future of Hydrogen.
 BMWi (2020) Nationales Reformprogramm 2020 – Die Nationale Wasserstoffstrategie.
 Wietschel M, et al. (2021) Metastudie Wasserstoff – Auswertung von Energiesystemstudien: Studie im Auftrag des Nationalen Wasserstoffrats.
 Forschungstelle für Energiewirtschaft (2021) eXtremOS- Findings: How do extreme scenarios affect the European energy system? https://extremos.ffe.de/#findings. Accessed 14 June 2021.
 Agora Energiewende and AFRY Management (2021) No-regret hydrogen: Charting early steps for H₂ infrastructure in Europe.
 Hübner T, et al. (2021) European Steel with Hydrogen. http://ffe.de/veroeffentlichungen/ffe-discussion-paper-european-steel-with-hydrogen/. Accessed 13 June 2021.
 Pichlmaier S, Hübner T, Kigle Stephan (2019) Welche strombasierten Kraftstoffe sind im zukünftigen Energiesystem relevant? http://ffe.de/veroeffentlichungen/welche-strombasierten-kraftstoffe-sind-im-zukuenftigen-energiesystem-relevant/. Accessed 13 June 2021.