Towards Hydrogen Infrastructure: Advances and Challenges in Preparing for the Hydrogen Economy

Towards Hydrogen Infrastructure: Advances and Challenges in Preparing for the Hydrogen Economy lays out the fundamental needs and processes of a potential hydrogen-based economy.

This book begins by outlining the processes, theory, and technology underlying hydrogen energy, from production to storage and dissemination. Each chapter outlines the potential and the hurdles for developing each element toward a workable hydrogen infrastructure. The later parts consider the social, and environmental issues surrounding the hydrogen economy, and suggest updated governmental policies.

Presenting the needs of hydrogen energy infrastructure from development to practical implementation,

• Provides a basic overview of hydrogen energy processes, from production and storage to transportation and use.
• Considers in detail the potential needs and opportunities of future hydrogen economic infrastructure, identifies necessary developments, and lays out a roadmap toward a successful transition.
• Presents safety and environmental considerations for the potential hydrogen economy, and proposes governmental and regulatory policies to enable effective, safe, and sustainable use.

• Language: English
• Publisher: Elsevier Science
• Release date: Aug 22, 2023
• ISBN: 9780323955546

Book preview

Hydrogen Economy and International hydrogen strategy

1.1 Hydrogen Economy and International Hydrogen Strategies 3

1.2 Potential market failures inhibiting the development of a green hydrogen export industry 39

1.3 Global Hydrogen Economy and Hydrogen Strategy Overview 59

Chapter 1.1

Hydrogen economy and international hydrogen strategies

Joydev Manna

Hydrogen Energy Division, National Institute of Solar Energy, Gwal Pahari, Gurugram, Haryana, India

1.1.1 Introduction

As a consequence of the continuous increase in the world's population, huge development in the industrial sectors, and change in human lifestyle to consume more energy, the demand for energy will continue to rise. Till 2030, the world's primary energy demand is expected to increase by more than 50%.

Figure 1.1.1 Global energy consumption during 2010–2020.

Figure 1.1.2 Energy consumption for a different part of the world in terms of various primary energy sources.

Figure 1.1.3 Energy consumption by end-user sector during 2010–2020.

Figure 1.1.4 Carbon dioxide emission in the world during 2010–2021.

Figure 1.1.5 Global renewable energy share during 2018.

Figure 1.1.6 Growth of solar photovoltaics capacity globally.

1.1.2 Concept of the hydrogen economy

The production, use, storing, and handling of hydrogen is not an unknown process, and it has been extensively used in industrial sectors, especially in the petroleum and fertilizer industry. Hydrogen was first utilized to carry people in a hydrogen balloon, and it was subsequently used in several nations as town gas for street lighting until the 1960s.

Figure 1.1.7 Schematic diagram to show the various parts of the hydrogen economy [20].

1.1.3 Properties of hydrogen

The lightest element is hydrogen. It is a tasteless, odorless, colorless, and nontoxic gas that is present in the air at amounts of around 100 parts per million (ppm; 0.01%) and makes up 75% of all ordinary matter in the universe. Table 1.1.1 compares the fuel characteristics of hydrogen with those of other commonly used fuels. The distinct combustion properties of hydrogen are what allow HICE to burn cleanly and function effectively. Its wide range of flammability, low ignition energy, short quenching distance, high autoignition temperature, the fast flame speed at stoichiometric ratios, high diffusivity, and extremely low density are among the qualities that make it useful as a combustible fuel. The relative heating value of hydrogen and other fossil fuels is shown in Fig. 1.1.8[5]. Compared to methane and gasoline, hydrogen has a far wider flammability range of 4–75% by volume with air. Because of this, hydrogen may burn in an engine at a variety of fuel–air ratios, including lean ratios, resulting in complete combustion, improved fuel efficiency, and a decrease in the number of pollutants like nitrogen oxide (NOx) due to reduced combustion temperature. As hydrogen has a very low ignition energy (0.02 mJ), it can quickly ignite lean mixtures and power engines. The low ignition energy has the unfortunate side effect of making hot gases and hot spots on the cylinder's potential sources of ignition, leading to issues with premature ignition and flashback. Due to hydrogen's broad range of flammability, a hot spot can ignite practically any mixture. The quenching distance of hydrogen is rather short—about three times that of petrol. The likelihood of backfire may rise with a shorter quenching distance. Because hydrogen has a comparatively high autoignition temperature, a hydrogen engine can use a higher compression ratio than a hydrocarbon engine, which improves the engine's thermal efficiency. Hydrogen has a rapid flame. It is also true that in the event of a hydrogen leakage, it spreads quickly due to hydrogen's extremely high diffusivity in the air.

Table 1.1.1

Figure 1.1.8 Heating values of commonly used fuels.

1.1.4 Overview of hydrogen production methods

A variety of carbonaceous feedstocks and/or water can be converted into hydrogen utilizing a variety of processes. Gasification and reforming processes such as steam methane reforming and partial oxidation/auto-thermal reforming can transform coal, NG, petroleum fractions, and biomass into hydrogen. Different hydrogen production methods used in industries are depicted in Fig. 1.1.9. Globally, about 95% of the hydrogen requirement is produced by fossil fuels. Depending on the hydrogen production methods and amount of carbon oxide emitted, hydrogen is color-coded (Table 1.1.2). Although, there is no universal agreement over these color codes. These hydrogen production technologies are discussed briefly in the following sections.

Figure 1.1.9 Industrial hydrogen production methods.

Table 1.1.2

*It is considered that CO2 emitted during gasification is equal to the amount of CO2 absorbed by the plant during its lifetime.

1.1.4.1 Steam methane reforming

Industrially, most hydrogen is produced by the steam methane reforming (SMR) process. In SMR process, initially, syngas (CO + H2) is produced which is followed by a water gas shift reaction to generate further quantities of hydrogen. Typically, the efficiency of the SMR process is 70–85%. In this process, around 9–12 tons of carbon dioxide is produced (depending upon the quality of feedstock) per ton of hydrogen.

1.1.4.2 Partial oxidation

Natural gas and other heavy hydrocarbons usually furnace oil, whose further treatment and utilization is difficult, are used to produce syngas using limited amount of oxygen which is known as partial oxidation or POX process. The thermal efficiency of this process is generally 60–75%. This process also releases a substantial amount of GHGs.

1.1.4.3 Autothermal reforming

Autothermal reforming (ATR) combines steam reforming (SR) and partial oxidation (POX) processes. ATR procedure creates a thermally neutral process by utilizing SR to boost hydrogen production while using the POX to generate heat. ATR is frequently carried out with less pressure than POX. This process does not require an external heat source for the reactor because POX is exothermic and ATR includes POX. However, to provide pure oxygen to the reactor, it either needs an expensive and complicated oxygen separation device, or the resulting gas is diluted with nitrogen, necessitating gas separation and purification procedures. Table 1.1.3 compares these three processes.

Table 1.1.3

1.1.4.4 Coal gasification

In the coal gasification process, steam and a carefully controlled concentration of air/oxygen are used to burn coal to form syngas. This process is known for the last couple of centuries and was used to produce town gas or coal gas for municipal lighting and heating purposes. According to estimates, the gasification process is currently used to manufacture more than 30% of the methanol and around 25% of the ammonia in the globe. The typical thermal efficiency of this process is 35–50%. The hydrogen generation through the biomass gasification process is similar to the coal gasification process.

1.1.4.5 Petroleum coke gasification

Petroleum coke can also be used to produce hydrogen-rich syngas using a similar process as coal gasification. However, the syngas obtained from petroleum coke gasification is a mixture of H2, CO, and hydrogen sulfide (H2S) gas.

1.1.4.6 Electrolysis

Hydrogen gas can be created by splitting water with electricity in an electrolyzer. Globally about 4% of hydrogen is produced by electrolysis. The conversion efficiency of electrolysis is around 52–69% which is expected to reach up to 80% by 2030.

Table 1.1.4

1.1.4.7 Sustainable hydrogen production methods

The current hydrogen production methods based on fossil fuels are responsible for the emission of around 830 Mt of CO2 annually. For sustainable hydrogen production, the energy and feedstocks used ought to be renewable in nature. Also, the method of hydrogen production must be cost-effective [14].

Figure 1.1.10 Sustainable hydrogen production methods.

1.1.5 Overview on hydrogen storage methods

Since hydrogen has a low density at room temperature, it releases little energy per unit volume for on-board uses. This is the major issue with hydrogen gas. Therefore, a proper hydrogen storage system is needed to improve its energy density. The hydrogen storage systems needed should have some important properties and selection criteria such as, high volumetric and gravimetric hydrogen capacity, operation in ambient condition, fast refueling, minimum energy loss during operation and low cost. United States Department of Energy (US DOE) has set a technical performance target (Table 1.1.5) for hydrogen storage systems for onboard light-duty vehicles. Currently, available storage options are discussed in the following sections.

Table 1.1.5

1.1.5.1 Compressed storage of hydrogen

Physically, hydrogen can be stored in liquid or gas form. It can also be stored within solids (absorption) or on the surfaces of solids (adsorption). Gaseous storage of hydrogen requires high-pressure to increase the storage density. A compressor for raising pressure and pressure vessel (tanks) for storage of compressed hydrogen are needed. Hydrogen tanks for storage of compressed hydrogen at 350 bar and 700 bar pressure are used globally. Compressed gas storage is the well-established technology and available storage tanks can be classified based on their types. Table 1.1.6 provides features of each type of hydrogen storage tank. Type III and IV pressure vessels are suitable for on-board hydrogen storage in HFVs. In type IV cylinders (Fig. 1.1.11), expensive carbon-fiber composite material is used to provide strength to withstand the high pressure of the hydrogen gas. These cylinders are 70% lighter than steel cylinders, safe, and durable with a lifespan of around 20 years. However, use of carbon fiber composites increases the cost of the hydrogen storage tanks.

Table 1.1.6

Figure 1.1.11 Cross-section view of type IV hydrogen storage tank [21].

1.1.5.2 Hydrogen storage in liquid state

Cryogenic temperature is needed to store hydrogen in liquid state because of very low boiling point of hydrogen at atmospheric pressure (−252.8°C). Currently, the liquefaction of hydrogen is performed using the Claude process. This process of producing liquid hydrogen (H2) is energy intensive. Theoretically, the minimum energy requirement for liquefaction of hydrogen depends on initial hydrogen pressure, the temperature difference between atmosphere and liquid hydrogen and lastly, the rate of ortho–para hydrogen conversion. It has been estimated that for 0.1 MPa hydrogen feed, around 3.92 kWh/kg of H2 is consumed. Insulated cylinders with safety features have been developed to store hydrogen in liquid state. BMW developed and used their liquid storage tanks with 170 L liquid hydrogen capacity having bi-layered highly insulated tank in BMW Hydrogen 7 car. Japan has also developed a liquid hydrogen storage site in Kobe port where hydrogen is liquefied at −253°C and stored at −162°C. Liquid hydrogen is also used in spacecraft as a fuel. Loss of hydrogen gas due to boiling off is a crucial issue in liquid state hydrogen storage method. Table 1.1.7 shows the materials suitable for liquid hydrogen storage and handling.

Table 1.1.7

1.1.5.3 Hydrogen storage in solid materials

Several solid-state hydrogen storage materials were proposed in recent years that can take up and release hydrogen at a specific temperature and pressure. The operational condition of such hydrogen storage materials should match with the operation conditions of the fuel cells, and it is always targeted to be operated as per the given condition by US DOE (Table 1.1.5). The solid-state hydrogen storage materials can take up hydrogen in terms of the following two mechanisms:

(a) Physisorption: This means physical adsorption of hydrogen on the surface of the material. In this process, hydrogen molecules will be bonded by weak van der Waals forces of the material. Physisorption of hydrogen is mainly studied on materials with the higher surface area such as, for example, nanocarbons, metal organic frameworks (MOF) and polymers, etc.

(b) Chemisorption: This means the chemical absorption of hydrogen into the materials crystal or chemical structure. Hydrogen molecules split off into hydrogen atoms during this process, and they chemically bonded with the atoms of the host materials. Various metals, metal alloys, and chemical compounds are tested for chemisorption of hydrogen. The main advantage of storing hydrogen in chemisorbed form is the high volumetric storage density. However, this process requires a thermal management system to adsorb and release the hydrogen from the storage system. Most of the chemical storage methods are found to be either energy intensive or nonreversible in nature with few exceptions. Operating conditions (temperatures and pressures) of these materials could be in wide range depending on the physical and chemical properties of the materials. Metal hydrides such as LaNi5, TiFe, etc. have shown reversibility at moderate temperature and pressure. R&D on metal hydride storage materials has been carried out extensively and has led to improvement in the hydrogen storage capacity of metal hydrides to about ∼2.5 wt%. Complex hydrides (alanates, boranes, etc.) are other categories of solid storage materials which can store high amount (5–18 wt%) of hydrogen but are nonreversible in nature and requires high temperature (100–1000°C) to adsorb and desorb hydrogen.

1.1.5.4 Hydrogen storage for stationary applications

High gravimetric hydrogen storage capacity is essential for automotive and mobile applications as there is weight constrain in a moving vehicle. However, for stationary applications, the volumetric hydrogen storage capacity is the important parameter, as weight will not play any important role in a stationary energy storage system. Type I or II cylinders are generally used for stationary hydrogen storage applications.

Figure 1.1.12 Underground hydrogen storage possibilities.

1.1.6 Overview on hydrogen supply and delivery methods

An extensive hydrogen transport and distribution infrastructure must be developed for the successful implementation of hydrogen economy. Currently, hydrogen is transported and delivered using trailers in terms of gaseous compressed hydrogen and liquid hydrogen. In some cases, pipelines are also used for delivery of gaseous hydrogen. As of now, only concept studies have been developed for maritime hydrogen transport.

1.1.7 Overview on application of hydrogen

Hydrogen has been mostly used in industrial sectors as feedstocks for decades. It has been primarily used in chemical and petrochemical industry for the production of various chemicals and petroleum products. In petrochemical industries, hydrogen is used mainly in two processes known as hydro-cracking and hydro-treating. In hydrocracking, the larger molecules of crude oil break down to smaller molecules whereas in hydrotreating, hydrogen is used for treatment of petrochemicals, for example, sulfur removal from the oil. In the fertilizer industries, ammonia is produced using hydrogen via Haber–Bosch Process. The produced ammonia is further used for the production of various fertilizers such as urea, ammonium nitrate, etc. In addition, hydrogen is also used for as a cooling agent in thermal power plants, as a reducing agent in float glass production, as a protective gas for development of semiconductors, for welding and cutting and for hydrogenation in the food industry as well as rocket fuel. Fig. 1.1.13 shows the different industrial areas in which hydrogen is used. Ramachandran et al. [1] have reviewed the use of hydrogen in industrial sectors. Hydrogen could also be used to decarbonize the hard-to-abate industrial sectors such as the manufacturing of steel and cement, etc.

Figure 1.1.13 Use of hydrogen in different industrial sectors.

1.1.7.1 Role of fuel cells in hydrogen economy

A fuel cell is an electrochemical device that converts chemical energy from a fuel (usually hydrogen) and an oxidizing agent (often oxygen) into electrical energy using two redox reactions. Fuel cells, in contrast to most batteries, need a steady supply of fuel and oxygen (or air) to maintain the chemical reaction. On the other hand, a battery normally gets its chemical energy from materials that are already present there. Fuel cells can continually generate power if fuel and oxygen are available. Fig. 1.1.14 shows a typical fuel cell system for power generation application. Fuel cells come in a variety of forms, but they all share the same three essential parts: an anode, a cathode, and an electrolyte [16]. Ions (mostly proton) can move between the fuel cell's two sides through the electrolyte. At the anode, fuel (hydrogen) is subjected to oxidation reactions that generate ions (usually protons and electrons). Ions (protons) go from the anode to the cathode through the electrolyte. Whereas electrons go across an external circuit from the anode to the cathode and as a result direct current (DC) electricity is generated. At the cathode, protons, electrons, and oxygen react to produce water vapor. Depending on the fuels used, fuel cells also produce heat and very small quantities of nitrogen dioxide and other pollutants in addition to water vapor. Fuel cells typically have an energy efficiency of 40–60%, however, by utilizing waste heat in a cogeneration system, it is feasible to get efficiencies of up to 85%.

Figure 1.1.14 Components of a typical fuel cell energy generation system [23].

(a) Alkaline fuel cells (AFC)

(b) Proton exchange membrane fuel cells (PEMFC)

(c) Direct methanol fuel cells (DMFC)

(d) Molten carbonate fuel cells (MCFC)

(e) Solid oxide fuel cells (SOFC)

(f) Phosphoric acid fuel cells (PAFC)

Table 1.1.8

1.1.8 Hydrogen safety

In comparison to other fuels, hydrogen has by far the lowest ignition energy (see Table 1.1.1). Additionally, hydrogen shows the greatest spread in mixes with air in the explosion or detonation range. As a result, the creation of hydrogen and air mixes in uncontrolled conditions must be strictly avoided as there is the considerable potential of catastrophic events, mostly due to the low ignition energy and the broad detonation range. Due to these characteristics and the fact that hydrogen is 15 times lighter than air, an adjusted safety strategy is required to reap the benefits of hydrogen without subjecting people to unwarranted hazards. Due to low molecular size, ease of leakage as a gas, buoyancy, and metal embrittlement properties, hydrogen storage and use provide unique challenges that must be taken into account in order to ensure safe operation. Liquid hydrogen presents additional challenges due to its low temperature and higher energy density. However, hydrogen has no hazard classification in terms of toxicity or inherent reactivity. Prevention methods to avoid hydrogen hazards include:

(a) Purging of gas lines or storage chambers by inert gas such as N2 before transferring hydrogen.

(b) Ignition sources should be avoided.

(c) Materials with proper codes and standards should be used for hydrogen handling.

(d) Hydrogen sensors and fire alarms must be installed.

(e) Proper ventilation is necessary.

1.1.9 International strategies on hydrogen

Due to the number of advantages of hydrogen over fossil fuels, many governments are giving priority to use of hydrogen in their policies. Global policymaking is becoming increasingly influenced by the climate change issues, as well as local air quality, supply security, and energy dependence. For these reasons, the European Commission's energy system has identified the hydrogen economy as one of its long-term priorities. In addition to Europe, the hydrogen vision is also being considered in the United States and Japan, and various national hydrogen energy initiatives have already been formed or are in the process of being developed [17]. As a result, both nationally and internationally, funding for fuel cell and hydrogen research has lately grown. It takes more than just establishing the correct payback time to put advanced, highly innovative technology, like hydrogen applications, into practice. A transition to a sustainable energy system necessitates adjustments at many societal and economic levels. To aid in the efficient and advantageous integration of hydrogen into their energy systems, many industrialized nations and regions are now developing their own hydrogen roadmaps. Fig. 1.1.15 shows different countries and their status of hydrogen strategy. Twelve nations, including the EU, have released their national hydrogen policies to date; nine of those publications came out just last year. There is a definite acceleration in government interest, supported maybe by recent COP26 acting as a stimulant. Other 20 additional nations are presently formulating their policies, several of which aim to publish within the next few years. A few nations have had a significant influence with their hydrogen policies. Japan's early commitment sparked interest in the Asian-Pacific area, leading to the publication of own policies by South Korea and Australia shortly after. Germany was a pioneer in Europe and assisted in advancing the EU hydrogen policy. Chile has made significant progress in Latin America, and several of its neighbors are also implementing their own methods.

Figure 1.1.15 Different countries as per their status of hydrogen strategy.

1.1.10 Summary

The world is witnessing a new era of energy transition which aims towards decarbonization of the energy sector. This energy transition is getting accelerated by several factors which include increasing energy demand, depleting fossil fuel reserves, environmental and climate change concerns, and also government regulations and actions to minimize GHG emissions to contain the global average temperature rise. It is believed that hydrogen can play an important role in this decarbonization process. The energy economy encompassing hydrogen as an energy carrier is named as hydrogen economy comprising four important components associated with it: hydrogen production, its storage, transportation, and utilization.

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Chapter 1.2

Potential market failures inhibiting the development of a green hydrogen export industry

Lee V. Whitea, David Gourlayb and Emma Aisbettc*

aSchool of Regulation and Global Governance, Australian National University, Canberra, ACT, Australia

bZero Carbon Energy for the Asia-Pacific Grand Challenge, Australian National University, Canberra, ACT, Australia

cCollege of Law, Australian National University, Canberra, ACT, Australia

*Authors are listed in reverse alphabetical in recognition of even distribution of contributions to the work.

1.2.1 Introduction

Hydrogen is once again emerging as a potent energy carrier and could be an important component of a transition to zero-emissions energy systems. While hydrogen can be produced in a number of ways, green hydrogen—that is, hydrogen produced from renewable energy sources—has the greatest ability to contribute to the goals of climate change mitigation. Green hydrogen has the potential to support the export of renewable energy from renewable-rich nations to energy-resource-constrained nations such as Japan and Germany. Although relative endowments of natural resources for green hydrogen production vary substantially across countries, the required resources are more widely distributed than fossil fuel resources. Green hydrogen thus has geopolitical advantages as an energy export/import allowing diversification and not necessarily reliant on pipeline infrastructure, and could also be a key export diversification strategy for a number of lower and middle-income countries, such as Namibia and Chile, that have limited reserves of fossil fuels for export but have abundant resources to support renewable electricity