Applications & Pathways

Shipping accounts for about 3% of global CO2 emissions. In order to achieve the target set by the Paris Agreement IMO introduced their GHG strategy. This strategy envisages 50% emission reduction from international shipping by 2050 compared with 2008. This target cannot be fulfilled if conventional fuels are used. Amongst others hydrogen is considered to be one of the strong candidates as a zero-emissions fuel. Yet concerns around the safety of its storage and usage have been formulated and need to be addressed. “Safety” in this article is defined as the control of recognized hazards to achieve an acceptable level of risk. This article aims to propose a new way of comparing two systems with regard to their safety. Since safety cannot be directly measured fuzzy set theory is used to compare linguistic terms such as “safer”. This method is proposed to be used during the alternative design approach. This approach is necessary for deviations from IMO rules for example when hydrogen should be used in shipping. Additionally the properties of hydrogen that can pose a hazard such as its wide flammability range are identified.

Hydrogen is a promising avenue for decarbonising energy systems and providing flexibility. In this paper the JRC-EU-TIMES model – a bottom-up technology-rich model of the EU28 energy system – is used to assess the role of hydrogen in a future decarbonised Europe under two climate scenarios current policy initiative (CPI) and long-term decarbonisation (CAP). Our results indicate that hydrogen could become a viable option already in 2030 – however a long-term CO₂ cap is needed to sustain the transition. In the CAP scenario the share of hydrogen in the final energy consumption of the transport and industry sectors reaches 5% and 6% by 2050. Low-carbon hydrogen production technologies dominate and electrolysers provide flexibility by absorbing electricity at times of high availability of intermittent sources. Hydrogen could also play a significant role in the industrial and transport sectors while the emergence of stationary hydrogen fuel cells for hydrogen-to-power would require significant cost improvements over and above those projected by the experts.

Maritime transport faces increasing pressure to reduce its greenhouse gas emissions to be in accordance with the Paris Agreement. For this to happen low- and zero-carbon energy solutions need to be developed. In this paper we draw on sustainability transition literature and introduce the technological innovation system (TIS) framework to the field of maritime transportation research. The TIS approach analytically distinguishes between different innovation system functions that are important for new technologies to develop and diffuse beyond an early phase of experimentation. This provides a basis for technology-specific policy recommendations. We apply the TIS framework to the case of battery-electric and hydrogen energy solutions for coastal maritime transport in Norway. Whereas both battery-electric and hydrogen solutions have developed rapidly the former is more mature and has a strong momentum. Public procurement and other policy instruments have been crucial for developments to date and will be important for these technologies to become viable options for shipping more generally.

Fuel cells and hydrogen (FCH) could bring significant environmental benefits across the energy system if deployed widely: low carbon and highly efficient energy conversions with zero air quality emissions. The socio-economic benefits to Europe could also be substantial through employment in development manufacturing installation and service sectors and through technology export. Major corporations are stressing the economic and environmental value of FCH technologies and the importance of including them in both transport and stationary energy systems globally while national governments and independent agencies are supporting their role in the energy systems transition.

Recognising the potential economic and industrial benefits from a strong FCH supply chain in Europe and the opportunities for initiatives to support new energy supply chains the FCH 2 JU commissioned a study to evaluate for the first time the value added that the fuel cell and hydrogen sector can bring to Europe by 2030.

The outputs of the study are divided into three reports:

• A ‘Summary’ report that provides a synthetic overview of the study conclusions;
• a ‘Findings’ report that presents the approach and findings of the study;
• and an ‘Evidence’ report  that provides the detailed background information and analysis that supports the findings and recommendations.

Multiple indicators suggest that the FCH sector is starting to grow and poised to grow fast. In fact this growth must be relatively rapid to create both the size of industry and the mature supply chains required for it to be self-sustaining. The supply chain is currently global and likely to remain so and Europe occupies a strong position within it. The study has concluded and provided evidences showing that the FCH sector offers Europe a chance to benefit economically and environmentally from an emerging industry and strengthen its position in clean technologies generally.

The Value Chain study complements the Hydrogen Roadmap for Europe recently published by the FCH 2 JU. This lays out a pathway for the large-scale deployment of hydrogen and fuel cells to 2050 in order to achieve a 2-degree climate scenario. This study also quantified socio-economic and environmental benefits but with important differences in scope between the two studies. The Hydrogen Roadmap for Europe looked at the wider picture quantifying the scale of FCH roll-out needed to meet the 2-degree scenario objectives. It assessed the socio-economic impacts of a sector of that scale looking top-down at the entire FCH value chain. The Value Chain study presented here is a narrower and more detailed bottom-up assessment of the value-added in manufacturing activities and the immediate ecosystem of suppliers that this is likely to create.

Today electricity & heat generation transportation and industrial sectors together produce more than 80% of energy-related CO₂ emissions. Hydrogen may be used as an energy carrier and an alternative fuel in the industrial residential and transportation sectors for either heating energy production from fuel cells or direct fueling of vehicles. In particular the use of hydrogen fuel cell vehicles (HFCVs) has the potential to virtually eliminate CO₂ emissions from tailpipes and considerably reduce overall emissions from the transportation sector. Although steam methane reforming (SMR) is the dominant industrial process for hydrogen production environmental concerns associated with CO₂ emissions along with the process intensification and energy optimization are areas that still require improvement. Metallic membrane reactors (MRs) have the potential to address both challenges. MRs operate at significantly lower pressures and temperatures compared with the conventional reactors. Hence the capital and operating expenses could be considerably lower compared with the conventional reactors. Moreover metallic membranes specifically Pd and its alloys inherently allow for only hydrogen permeation making it possible to produce a stream of up to 99.999+% purity.

For smaller and emerging hydrogen markets such as the semiconductor and fuel cell industries Pd-based membranes may be an appropriate technology based on the scales and purity requirements. In particular at lower hydrogen production rates in small-scale plants MRs with CCUS could be competitive compared to centralized H₂ production. On-site hydrogen production would also provide a self-sufficient supply and further circumvent delivery delays as well as issues with storage safety. In addition hydrogen-producing MRs are a potential avenue to alleviate carbon emissions. However material availability Pd cost and scale-up potential on the order of 1.5 million m3/day may be limiting factors preventing wider application of Pd-based membranes.

Regarding the economic production of hydrogen the benchmark by the year 2020 has been determined and set in place by the U.S. DOE at less than $2.00 per kg of produced hydrogen. While the established SMR process can easily meet the set limit by DOE other carbon-free processes such as water electrolysis electron beam radiolysis and gliding arc technologies do not presently meet this requirement. In particular it is expected that the cost of hydrogen produced from natural gas without CCUS will remain the lowest among all of the technologies while the hydrogen cost produced from an SMR plant with solvent-based carbon capture could be twice as expensive as the conventional SMR without carbon capture. Pd-based MRs have the potential to produce hydrogen at competitive prices with SMR plants equipped with carbon capture.

Despite the significant improvements in the electrolysis technologies the cost of hydrogen produced by electrolysis may remain significantly higher in most geographical locations compared with the hydrogen produced from fossil fuels. The cost of hydrogen via electrolysis may vary up to a factor of ten depending on the location and the electricity source. Nevertheless due to its modular nature the electrolysis process will likely play a significant role in the hydrogen economy when implemented in suitable geographical locations and powered by renewable electricity.

This review provides a critical overview of the opportunities and challenges associated with the use of the MRs to produce high-purity hydrogen with low carbon emissions. Moreover a technoeconomic review of the potential methods for hydrogen production is provided and the drawbacks and advantages of each method are presented and discussed.

There is a need for alternative marine fuels in order to reduce the environmental and climate impacts of shipping in the short and long term. This study assesses the prospects for seven alternative fuels for the shipping sector in 2030 including biofuels by applying a multi-criteria decision analysis approach that is based on the estimated fuel performance and on input from a panel of maritime stakeholders and by considering explicitly the influence of stakeholder preferences. Seven alternative marine fuels—liquefied natural gas (LNG) liquefied biogas (LBG) methanol from natural gas renewable methanol hydrogen for fuel cells produced from (i) natural gas or (ii) electrolysis based on renewable electricity and hydrotreated vegetable oil (HVO)—and heavy fuel oil (HFO) as benchmark are included and ranked by ten performance criteria and their relative importance. The criteria cover economic environmental technical and social aspects. Stakeholder group preferences (i.e. the relative importance groups assign to the criteria) influence the ranking of these options. For ship-owners fuel producers and engine manufacturers economic criteria in particular the fuel price are the most important. These groups rank LNG and HFO the highest followed by fossil methanol and then various biofuels (LBG renewable methanol and HVO). Meanwhile representatives from Swedish government authorities prioritize environmental criteria specifically GHG emissions and social criteria specifically the potential to meet regulations ranking renewable hydrogen the highest followed by renewable methanol and then HVO. Policy initiatives are needed to promote the introduction of renewable marine fuels.

The maritime shipping sector is a major contributor to CO₂ emissions and this figure is expected to rise in coming decades. With the intent of reducing emissions from this sector this research proposes the utilization of the jet stream to transport a combination of cargo and hydrogen using airships or balloons at altitudes of 10–20 km. The jet streams flow in the mid-latitudes predominantly in a west–east direction reaching an average wind speed of 165 km/h. Using this combination of high wind speeds and reliable direction hydrogen-filled airships or balloons could carry hydrogen with a lower fuel requirement and shorter travel time compared to conventional shipping. Jet streams at different altitudes in the atmosphere were used to identify the most appropriate circular routes for global airship travel. Round-the-world trips would take 16 days in the Northern Hemisphere and 14 in the Southern Hemisphere. Hydrogen transport via the jet stream due to its lower energy consumption and shorter cargo delivery time access to cities far from the coast could be a competitive alternative to maritime shipping and liquefied hydrogen tankers in the development of a sustainable future hydrogen economy.

COVID-19 has led to a global crisis threatening the lives and livelihoods of the most vulnerable by increasing poverty exacerbating inequalities and damaging long-term economic growth prospects. The report Are We Building Back Better? Evidence from 2020 and Pathways for Inclusive Green Recovery Spending provides an analysis of over 3500 fiscal policies announced by leading economies in 2020 and calls for governments to invest more sustainably and tackle inequalities as they stimulate growth in the wake of the devastation wrought by the pandemic.

Setting up and operating a hydrogen refueling station is a critical part of current drive for fuel cell vehicles. In setting up a hydrogen refueling station (HRS) the investor concerns of the capacity of HRS the quality of hydrogen the capital requirement of the station and the modes of hydrogen supply; interestingly the supply modes of hydrogen further influences the safety of the station the cost of hydrogen the energy consumption of supply and the area of hydrogen supply section in a station. Hydrogen can be supplied to a HRS by the procurement of the merchant hydrogen from a central source with the central hydrogen supply mode (CHSM) or by an onsite production of hydrogen in the distributed hydrogen supply mode (DHSM). In this presentation the above factors are evaluated with respect to these two supply modes of hydrogen. It is concluded that the lower hydrogen cost and the smaller site area as well as the safer aspect of the public concern of safety can be realized with the choice of the distributed hydrogen supply mode by an onsite hydrogen production from methanol.

This discussion session interrogated the current understanding of hydrogen embrittlement mechanisms in steels. This article is a transcription of the recorded discussion of ‘Hydrogen in steels’ at the Royal Society Scientific Discussion Meeting ‘The challenges of hydrogen and metals’ 16–18 January 2017.

The text is approved by the contributors. E.L.S. transcribed the session. M.P. assisted in the preparation of the manuscript

Link to document download on Royal Society Website