净零未来中的氢储存（英）--牛津能源研究所.pdf

ENERGY TRANSITION ENERGY TRANSITION Hydrogen CHINA April 2023 December 2021 OIES PAPER: ET23 OIES PAPER: ET06 Aliaksei Patonia, Research Fellow, OIES Rahmatallah Poudineh, Head of Electricity Research, OIES Anders Hove, Research Associate, OIES Michal Meidan, Senior Research Fellow, OIES Philip Andrews-Speed, Senior Research Fellow, OIES Hydrogen storage for a net-zero carbon future The contents of this paper are the authors’ sole responsibility. They do not necessarily represent the views of the Oxford Institute for Energy Studies or any of its Members. i The contents of this paper are the authors’ sole responsibility. They do not necessarily represent the views of the Oxford Institute for Energy Studies or any of its members. Copyright © 2023 Oxford Institute for Energy Studies (Registered Charity, No. 286084) This publication may be reproduced in part for educational or non-profit purposes without special permission from the copyright holder, provided acknowledgment of the source is made. No use of this publication may be made for resale or for any other commercial purpose whatsoever without prior permission in writing from the Oxford Institute for Energy Studies. ISBN 978-1-78467-199-0 The contents of this paper are the authors’ sole responsibility. They do not necessarily represent the views of the Oxford Institute for Energy Studies or any of its Members. ii Abstract If a hydrogen economy is to become a reality, along with efficient and decarbonized production and adequate transportation infrastructure, deployment of suitable hydrogen storage facilities will be crucial. This is because, due to various technical and economic reasons, there is a serious possibility of an imbalance between hydrogen supply and demand. Hydrogen storage could also be pivotal in promoting renewable energy sources and facilitating the decarbonization process by providing long duration storage options, which other forms of energy storage, such as batteries with capacity limitations or pumped hydro with geographical limitations, cannot meet. However, hydrogen is not the easiest substance to store and handle. Under ambient conditions, the extremely low volumetric energy density of hydrogen does not allow for its efficient and economic storage, which means it needs to be compressed, liquefied, or converted into other substances that are easier to handle and store. Currently, there are different hydrogen storage solutions at varying levels of technology, market, and commercial readiness, with different applications depending on the circumstances. This paper evaluates the relative merits and techno-economic features of major types of hydrogen storage options: (i) pure hydrogen storage, (ii) synthetic hydrocarbons, (iii) chemical hydrides, (iv) liquid organic hydrogen carriers, (v) metal hydrides, and (vi) porous materials. The paper also discusses the main barriers to investment in hydrogen storage and highlights key features of a viable business model, in particular the policy and regulatory framework needed to address the primary risks to which potential hydrogen storage investors are exposed. The contents of this paper are the authors’ sole responsibility. They do not necessarily represent the views of the Oxford Institute for Energy Studies or any of its Members. iii Contents Abstract . ii Contents . iii Figures iii Tables . iv 1. Introduction . 1 2. Overview of the main types of hydrogen storage . 2 2.1. Pure hydrogen storage .3 2.1.1. Compressed hydrogen 3 2.1.2. Liquefied hydrogen 5 2.2. Synthetic hydrocarbons 5 2.2.1. Compressed and liquefied synthetic natural gas (SNG) 5 2.2.2. Synthetic gasoline (petrol) and diesel 6 2.3. Chemical hydrides 7 2.3.1 Ammonia and methanol . 7 2.3.2. Formic acid and isopropanol . 8 2.4. Liquid organic hydrogen carriers (LOHCs) .9 2.5. Metal hydrides 9 2.5.1. Elemental metal hydrides 9 2.5.2. Intermetallic hydrides 10 2.5.3 Complex metal hydrides . 10 2.6. Porous materials 11 2.6.1. Carbon-based materials 11 2.6.2. Metal-organic frameworks (MOFs) 11 2.7. Overall evaluation 12 3. Factors to consider for investment in hydrogen storage 12 3.1. Further technical and technology issues and challenges 14 3.2. Other factors, uncertainties, and barriers for investment in hydrogen storage . 16 4. Business models and policies for hydrogen storage . 21 4.1. Range of possible business models 22 4.2.1. Addressing the price risk . 23 4.2.2. Addressing the demand risk 24 4.2.3. Choosing an optimum business model for hydrogen storage 24 4.3. Further challenges and questions . 25 5. Conclusion 26 References 29 Figures Figure 1: Global hydrogen consumption by industry . 1 Figure 2: Volumetric hydrogen density and gravimetric hydrogen content of best performing substances for each type of major hydrogen storage options . 12 Figure 3: Approximate volume and total weight containing 100 kg of H2 of best performing substances for each type of major hydrogen storage options 14 Figure 4: Estimates of hydrogen storage need by 2050 vs. potential . 19 Figure 5: Range of possible business models . 23 The contents of this paper are the authors’ sole responsibility. They do not necessarily represent the views of the Oxford Institute for Energy Studies or any of its Members. iv Tables Table 1: Key characteristics of some major hydrogen storage options . 4 Table 2: Approximate indicators of hydrogenation/dehydrogenation, storage capacity and technology, market and commercial readiness levels for the viewed hydrogen storage options 13 Table 3: Key advantages and disadvantages of major hydrogen storage options 15 Table 4: Approximate capital, operation and maintenance costs of storing pure hydrogen in different forms (USD2017/kWh) 17 Table 5: Storage volume needed to accommodate Europe’s 2-week peak energy demand of 326 TWh 17 Table 6: Some key characteristics of the main geological options for underground hydrogen storage. 18 Table 7: TRL, MRL, CRL of various hydrogen storage alternatives and their aligned funding options . 20 The contents of this paper are the authors’ sole responsibility. They do not necessarily represent the views of the Oxford Institute for Energy Studies or any of its Members. 1 1. Introduction Hydrogen (H2) – the most abundant element in the universe – is widely viewed as a crucial element in the decarbonization strategies of many countries in recent years (US Energy Information Administration, 2022). This is so primarily because of its versatile potential applicability (e.g. it can be used as a fuel, feedstock, and means of energy storage) combined with the fact that it does not produce carbon dioxide (CO2) when combusted1 (Air Liquide, 2022). Moreover, in contrast to fossil fuels where deposits are geographically limited to specific geological conditions, green hydrogen – the H2 generated from water with renewable power through the electrolysis process – could potentially be produced anywhere in the world, though not with the same cost efficiency (Patonia and Poudineh, 2022). That is why an increasing number of countries have been enthusiastically setting green hydrogen production targets that would supposedly help them in reaching their decarbonisation targets or generate export revenues when they have abundant low-cost renewables (Power, 2021). At the same time, because of varying economic conditions as well as differing competitive advantage in producing low-cost decarbonized hydrogen, many countries also recognized the need to import hydrogen in order to achieve their net-zero carbon aspirations on time2. For this purpose, some have signed agreements and memoranda of understanding to explore the possibility of future hydrogen supplies (Landsvirkjun, 2020, RWE, 2021, dw, 2022). Others, for example Japan, have gone further and piloted first long-distance shipments of hydrogen and its derivatives (such as liquid organic hydrogen carriers and ammonia) from remote locations like Brunei and Saudi Arabia to their shores (Patonia and Poudineh, 2022). That is why, overall, in anticipation of the advent of a global hydrogen economy, both hydrogen production and transport aspects of the hydrogen value chain have already been focused on by scholars, policymakers, and energy practitioners. One crucial element of this value chain that has been insufficiently explored up to this point is storage. The importance of hydrogen storage cannot be overstated. No viable business model for hydrogen as an internationally or even locally traded commodity could possibly omit the fact that this substance in most cases will have to be stored at least right after its production and before its delivery to the end user. Obviously, with the current model of hydrogen use for industrial purposes (mostly oil refining and ammonia fertilizer production)3 (Figure 1), H2 has been consumed primarily close to its generation point so that both storage and transportation of this substance have not played a decisive role in its value chain (IEA, 2019). At the same time, if a hydrogen economy is ever to be created, this approach will no longer be the dominant form of the hydrogen value chain. In fact, increasing the tradability of hydrogen will require considering the peculiarities and challenges associated with preserving H2 in different quantities for various periods of time. Figure 1: Global hydrogen consumption by industry Source: WHA (2021) With the growing demand and accelerated manufacturing of H2 around the world, the need for hydrogen storage is likely to rise proportionally. The main driver of demand for hydrogen storage is likely to be the eventual imbalance between the production and consumption of hydrogen. For instance, in the future, 1 Although hydrogen is viewed as a substance that could be used for various decarbonisation purposes, it is most often regarded as an element that could potentially replace fossil fuels as sources of energy (Qazi, 2022). In this connection, if this replacement takes place in some form, hydrogen will not be a primary energy source (because it will have to be produced) but will rather serve the purpose of energy storage in a chemical form (Mohammadi-Ivatloo, Mohammadpour, and Anvari-Moghaddam, 2021). 2 For instance, in his address to the European Parliament, Frans Timmermans, the European Commissioner for Climate Action, admitted that ‘Europe [was] never going to be capable to produce its own hydrogen in sufficient quantities’ (Recharge, 2022a). 3 For instance, for ammonia production, hydrogen is normally generated from the main feedstock (usually, natural gas) as a part of the production process and is consumed on site (Patonia and Poudineh, 2020). 55%25% 10% 10% Ammonia (fertiliser) production Oil refining Methanol production Other The contents of this paper are the authors’ sole responsibility. They do not necessarily represent the views of the Oxford Institute for Energy Studies or any of its Members. 2 manufacturing rate of blue and turquoise H2 – hydrogen generated from fossil fuels with carbon capture, utilization, and storage (CCUS) – will be reasonably flat (linear) to provide the maximum efficiency (Megia et al, 2021). At the same time, this production pattern is unlikely to coincide with hydrogen demand all the time, which could be addressed through storage. Indeed, storage is already a key component of existing fossil fuel supply chains. More significantly, if hydrogen is produced through electrolysis using solar and wind power, the generation process will be intermittent. Here, apart from daily and seasonal variability associated with lower/ higher magnitude of wind speed and solar irradiation at different time of the day and year, weather conditions causing the so-called ‘Dunkelflaute’ events – anticyclonic gloomy windless days when little or no energy can be generated by wind and solar (Matsuo et al, 2020) – will significantly impact hydrogen production. As a result, H2 manufacturing may not coincide with the time of its peak consumption. Here again, hydrogen storage will be of critical use to meet make both the supply and demand, since the demand side may not be extremely responsive to overproduction or underproduction of hydrogen4. Apart from that, with the variable nature of wind and solar – the energy sources that are going to play an even greater role in a decarbonized energy system of the future – hydrogen storage could become a means of grid balancing when overproduction and underproduction issues occur. Currently, when renewable generation often has to be curtailed due to overgeneration or local networks issues, converting electrons into molecules and back through the power-to-X technologies could help to avoid these issues (ITM Power, 2022). As a result, H2 storage would play an extremely important role in the entire decarbonization process, since it would facilitate further spread of renewable energy sources through offering both backup and seasonal storage options where batteries and pumped hydro have significant capacity or geographical limitations5. This is so because natural gas, which is most often stored to contribute to meeting seasonal energy demand, is not a carbon-free solution and thus should be substituted with a more sustainable one. In this context, an increasing number of researchers view hydrogen and its derivatives as such substitutes (Guerra et al, 2020). On the other hand, despite all the advantages of hydrogen storage as well as the opportunities that it may bring, keeping and preserving H2 for later transportation or consumption does not appear to be the easiest task. In fact, due to the very nature of this simplest of all elements that is easily lost into the atmosphere, hydrogen storage is generally a challenging undertaking6. Additionally, because of its extremely low volumetric energy density, pure H2 needs to be either compressed or liquefied. With both processes being energy intensive and expensive7, it may not always be economic to store hydrogen in gaseous or liquid forms. In these situations, converting hydrogen into other substances that are easier to handle and store can be advantageous. At the moment, however, there is no clear stance on which hydrogen storage option is the one that will offer more advantages than the rest. As a result, it is still uncertain if there will be a single preferred variant that will be adopted by most stakeholders in the to-be-created hydrogen economy. In fact, different hydrogen storage solutions are likely to be preferred depending on circumstances. This paper thus evaluates the relative merits of alternatives in different applications. The outline of the paper is as follows. Section 2 provides an overview and comparison of major types of hydrogen storage options that are currently being explored and considered by scholars, policymakers and businesses. Factors to consider for investment in hydrogen storage and discussion on major barriers for such an investment are presented in Section 3. Section 4, in tu