Insights and Guidance for China’s Offshore CO₂ Storage Development: Evidence from Global Experience

Abstract

Through extensive data research and analysis, this paper comprehensively summarizes the status and key insights of global carbon dioxide capture and storage (CCS) development. It aims to gain a comprehensive understanding of the relevant policies, technologies, and security measures adopted by major countries in their CCS development processes. Furthermore, it explores the existing status and limitations of China’s offshore development efforts, while providing valuable recommendations for enhancing China’s offshore CCS initiatives, as well as serving as a reference for other nations worldwide. Offshore CCS plays a crucial role for China to achieve the development target of carbon peak and carbon neutrality, due to its energy structure and industrial distribution. While China possesses significant offshore CCS potential, achieving commercialization still requires substantial efforts. To facilitate the process and draw insights from successful experiences in other countries, this paper illustrates the characteristics and generalizes the experience of offshore CCS industry practices in America, Europe and Japan, respectively. Furthermore, it is recommended that a new round of investigation into offshore CCS potential be conducted, while promoting integrated collaboration between geological surveying and marine scientific research. Additionally, further research on industrial policies and green financial strategies should be undertaken.

1. Introduction

To achieve the target of carbon peak and carbon neutrality, emission reduction and increase of carbon sink are the two fundamental paths [1]. As the largest active carbon pool on earth, the ocean has a huge carbon sink potential and negative emission prospect [2,3]. At present, a lot of countries around the world have taken offshore CCS (Carbon Dioxide Capture and Storage) as an important part of carbon emission reduction technology, and rely on geological survey and research institutions to effectively promote the development of the offshore CCS industry. As a major carbon emitter and a developing country, China’s resource endowment and development stage determine that, for a period in the future, fossil energy, and mainly coal, will still dominate China’s energy supply, so it is necessary to ease the pressure of emission reduction by ‘increasing carbon sink’. To carry out offshore CCS research is necessary to help achieve the goal of carbon peak and carbon neutrality.

2. The Significance of Offshore CCS

Carbon capture and storage (CCS) is essential for net zero emissions to be achieved in any economy using fossil fuels or releasing carbon in any other ways. In 2018, the IPCC special report Global Warming of 1.5 °C assessed 90 scenarios for achieving net zero emissions in the future, almost all of which would require CCS technology [4]. At present, there are two large available carbon storage options, geological storage and marine base. Because captured CO₂ (carbon dioxide) injected directly into the marine water column at great depth (more than 1000 m) is prohibited by the London Convention [5], this paper refers to Offshore CCS as injecting the CO₂ captured, which usually combines EOR (enhanced oil recovery) in offshore geological formations, which are mainly oil and gas reservoirs and deep saline aquifer [6] (Figure 1). Compared with onshore CCS, which more easily causes groundwater pollution and brings about regional environmental risks, offshore CCS has been preferred by countries around the world to achieve carbon neutrality. First, it is much safer. The storage site is far away from the aquifer and, besides the cap layer, there is more pressure and barrier of seawater on the surface layer, which greatly reduces the local risk. Second, it is easier to monitor. The pore water in the seabed is chemically like normal seawater and the formation pressure is easier to manage. Finally, the carbon storage potential is much greater. The offshore carbon storage potential is tens or even hundreds of times greater than the onshore counterpart [7].

The power generation industry is recognized as the most important industry to achieve the carbon peak and carbon neutrality goals. CCS technology applies very well in thermal power plants, especially for large point sources of CO₂ in coal-fired power plants. Carbon emission of China’s power generation industry accounts for 52% of total emissions, and thermal power generation exceeds 72% of total power supplies, most of which is in the southeast coastal areas [2,8]. The eastern part of China also has a large amount of carbon emissions, coming from the cement, steel, and chemical engineering industries [7]. For these industries, carbonization is a daunting task. Therefore, offshore CCS is necessary, given the current energy structure and industrial distribution in China.

3. The Overview and Experience of Global Offshore CCS

3.1. The United States

As the leader in CCS, America has almost half of the total CCS facilities in the world. At present, there are 10 commercial CCS facilities in operation, with a capacity of 25 million tons of CO₂. In addition, there are other 19 projects under development, which are at different phases [9]. Although the development of CCS in America is market-orientated, geoscientific institutions such as USGS (United States Geological Survey) also play a key role in it, and it has gradually formed a development system, which is guided by funding from the DOE (Department of Energy), supported by research from USGS and other scientific institutions, and driven by financial and tax policy incentives [10,11,12,13,14].

3.1.1. Government Efforts to Increase R&D Investment

Since 1997, DOE has been funding USGS and other scientific institutions, as well as enterprises in CCS research. So far, 140 projects have received support from DOE [11]. In 2016, to accelerate the commercialization of CCS, an innovative called Carbon SAFE (The Carbon Storage Assurance Facility Enterprise) was conducted by the DOE. The projects funded by Carbon SAFE focus on development of geologic storage sites for the storage of more than 50 million metric tons of CO₂ from industrial sources, and will improve understanding of project screening, site selection, characterization, and baseline monitoring, verification, accounting (MVA), and assessment procedures, as well as provide the information necessary to submit appropriate permits and design injection and monitoring strategies for commercial-scale projects. These efforts promote the quick development of CCS technology in the United States. In 2020, six of the eight new CCS facilities worldwide are funded by Carbon SAFE [15]. The rapid development of CCS projects in the United States is mainly attributed to government tax and subsidy policies. For instance, in 2020, the US Department of Energy provided $670 million to support CCS projects. Furthermore, in 2022, the DOE announced a $2.25 billion investment over the next five years for validating carbon dioxide geological sequestration and developing technologies to combat climate change and achieve carbon neutrality by 2050 [16,17,18].

3.1.2. Give Legal Responsibilities to USGS

USGS was given the explicit responsibility of CCS development and the potential evaluation of CO₂-EOR (Enhanced Oil Recovery) according to the Energy Independence and Security Act of 2007. In 2008, USGS launched the project Geological Survey and CCS Evaluation. Five years later, the CO₂ storage potential, onshore and offshore (only state-owned), of all states was completed (

Table 1. Mean estimates by the U.S. Geological Survey in 2012 for technically accessible storage resources (TASR) of carbon dioxide (CO₂) in deep storage assessment units (SAUs) in the United States [19].

Basin Name	TASR in Deep SAUs (Mt)	Percent of Basin TASR	Percent of National TASR
Alaska North Slope	56,000	21	2
Anadarko and Southern Oklahoma Basins	25,000	40	1
Bighorn Basin	350	20	0
Greater Green River Basin	20,000	52	1
Hanna, Laramie, and Shirley Basins	730	32	0
Los Angeles Basin	740	20	0
Permian Basin	19,000	31	1
San Joaquin Basin	1400	3	0
Uinta and Piceance Basins	710	19	0
U.S. Gulf Coast	310,000	18	11
Williston Basin	11,000	7	0
Wind River Basin	1400	17	0
Wyoming-Idaho-Utah Thrust Belt	24,000	54	1
Total	470,000		16

[Estimates are in millions of metric tons (megatons, Mt). Mean values sum to totals but are reported to only two significant figures. Deep SAUs are at depths greater than 13,000 feet (3962 m). The 46 deep SAUs are in 13 basins].

). The focus of this project was mainly on two areas [19,20]. One was to identify the geological and geochemical condition for commercializing CCS, which included the study of interactions between injected CO₂ and the reservoir and making comparisons between different reservoirs, in terms of benefits and risks. The other was to identify and evaluate the potential reservoirs. USGS is planning to build a database that integrates the evaluation results with the GIS (Geographic Information System). In addition, USGS wants to build seismic facilities around the CSS sites to predict the possible risk of earthquakes. For federally owned offshore areas, USGS, in conjunction with BOEM (Bureau of Ocean Energy Management), NETL (National Energy Technology Laboratory), and relevant state governments and industry, is conducting research on site selection and characterization (data collection, capacity/injectivity assessments, and modeling), seismic interpretation and evaluation, carbon storage potential assessment, etc., in areas of the U.S East Coast and Mexico Bay [6,21].

3.1.3. Introduce Tax Incentives

In the context of CCS development, tax credits have become the preferred incentive structure for the federal government to spur the deployment of, and unlock investment in, CCS. The carbon oxide sequestration credit-45Q—firstly enacted by the Energy Improvement and Extension Act of 2008—is a performance-based tax credit incentivizing carbon capture and sequestration or utilization. It provides a certain amount of monetary credit for carbon oxide that is permanently stored via usage, tertiary oil injection, or in geologic formations [9,22]. Regarded as the most progressive CCS-specific incentive by many, 45Q has already led to a series of project announcements. In fact, during 2020, 12 new large-scale facilities in development were added to the Institute’s project database from the United States alone, having been largely incentivized by the 45Q tax credit (

Table 2. US CCS facilities and storage hubs in development [9].

Facility	Source Industry	Storage	Financial Drivers
Wabash	Fertiliser Production	Geological	45Q, LCFS
Lake Charles Methanol	Methanol Production	EOR, Geological	EOR, 45Q
Dry Fork	Power Generation-Coal	EOR, Geological	EOR, 45Q
Tundra	Power Generation-Coal	EOR, Geological	EOR, 45Q
San Juan Generating	Power Generation-Coal	EOR, Geological	EOR, 45Q
Gerald Gentleman	Power Generation-Natural Gas	EOR	EOR, 45Q, LCFS
Velocys Bayou Fuels	Power Generation-Biomass	Geological	45Q, LCFS
Clean Energy Systems	Power Generation-Biomass	In evaluation	45Q, LCFS
Illinois Clean Fuels	Power Generation-Waste-to-Energy	Geological	45Q, LCFS
ZEROS	Power Generation-Waste-to-Energy	EOR	45Q
CarbonSafe Illinois Storage Hub	Multiple	EOR, Geological	EOR, 45Q
Mid-Continent Storage Hub	Multiple	EOR, Geological	EOR, 45Q
ECO2S Storage Hub	Multiple	Geological	45Q

).

3.2. Europe

Europe takes offshore CCS seriously, and sees it as an important method for addressing climate challenge. The European CCUS project primarily achieves carbon reduction by leveraging the EU carbon market and enhanced oil recovery (EOR) techniques [16,17]. At present, there are 15 offshore CCS facilities either in operation or under development (Figure 2, Table 1), most of which store CO₂ in the North Sea. It is planned that a total of 51 projects (only 2 onshore) will be deployed by 2030, when the annual carbon dioxide storage capacity will be 50 million tons [23]. To accelerate the development of offshore CCS, Europe has drawn on the expertise of geological and marine research institutes and, as a result, a comprehensive CCS research network has been set up. Additionally, the European Union considers CCUS to be a crucial technology for green hydrogen production. The European CCS Clean Hydrogen Initiative is currently in the planning and feasibility study phase, while the Netherlands is exploring the combination of CCUS and low hydrogen [18,24].

3.2.1. Establish International Science Projects

Several scientific projects have been established, including EU Geocapacity and CGS Europe (a pan-European coordination action on CO₂ geological storage), etc. Under these projects, a series of evaluations of CCS potential, both onshore and offshore, has been conducted by geological survey institutions. Taking the CGS Europe as an example, since it was founded in 2010, a total of 34 institutes from 28 counties have been involved. 30 of the 34 institutes are geological survey institutes, which come from countries such as Britain, France, Germany, Italy, Norway, and Finland [25]. Because of the project, geological survey institutes from these countries have regarded CCS as a crucial task for the transformation of geological work. CCS R&D centers were established, respectively, under the geological survey institutions in Britain and Nordic countries. These centers are mainly responsible for studies on sequestration and reservoir characterization, CO₂ injection and sequestration. As a result, offshore CCS potential in these countries has been basically evaluated [26,27,28]. In 2013, a CCS database was developed by the British Geological Survey, in partnership with the Finance Ministry of Britain as a national asset, making Britain the first country to release data about CCS potential. According to the database, Britain’s offshore CCS potential is 70 billion tons [27].

3.2.2. Take the Safety of the Ecosystem Seriously

In the face of potential risks that CCS may bring about, the British Geological Survey and Helmholtz Polar Marine Institute conducted several projects, including QLCS (Quantifying and Monitoring Potential Ecosystem Impacts of Geological Carbon Storage), ETT MMV (Energy Technologies Institute Measurement, Monitoring and Verification of CO₂ Storage) and STEMM-CCS (The Strategies for Environmental Monitoring of Marine Carbon Capture and Storage) [29]. These projects collectively represent over 12 years of dedicated research to assess environmental impacts and develop technologies for the detection, location, and quantification of potential leakage from offshore geological storage of CO₂. Because of these efforts, it turns out that offshore CCS is reliable. The main research contents of these projects include: (1) seabed ecological baseline survey; (2) sensitivity study of marine environment to identify the potential leakage of carbon dioxide sequestration; (3) identification, monitoring, and quantification of seafloor carbon dioxide leakage; (4) development of long-term monitoring; (5) Economic valuation, monitoring, and remediation of carbon dioxide leakage costs. In February 2020, the British Geological Survey completed its quest to test techniques for environmental monitoring over a marine CO₂ storage site in the UK North Sea; it then further improved near seabed leakage characterization capabilities, and delivered a first marine CCS demonstration level ecological baseline [29].

3.2.3. Accelerate Scientific Results Transformation

To make the scientific achievements on offshore CCS applicable, the European Union has put oil and gas companies such as Shell, Total Energies and Statoil, into its scientific projects, where these companies are encouraged to lead in the demonstrative projects for offshore CCS. In 2016, when the project STEMM-CCS was implemented, British National Marine Institute and Helmholtz Marine Institute were involved, together with Shell [30]. In 2020, Shell started to lead in the project’s environmental monitoring effort [31]. Another example is Nordic CCS, which is a virtual CCS networking platform aiming for increased CCS deployment in the five Nordic countries. The success of Nordic CCS is dependent on active involvement from industrial partners, including the Swedish Geological Survey, Greenland Geological Survey and Swedish Environmental Research Institute, as well as a number of companies involved, such as Statoil and Reykjavik Energy [32]. It is worth mentioning that the British Geological Survey is the leader in CCS. Many of its scientific achievements are commercially competitive.

3.3. Japan

As a country made up of islands, Japan does not have large continental territory. Since the mid-1990s, Japan has been experimenting on offshore CCS and making it an important component of ocean development strategy. At present, there are six offshore CCS facilities in Japan, but none is commercialized [9]. To promote the growth of offshore CCS, Japanese government has been working with Japanese industries to forge a system bringing together business opportunities, scientific research and public undertakings. Japan prioritizes carbon recycling research and considers CCUS technology as the key to achieving society’s decarbonization goals. They have developed relevant plans and roadmaps, and conducted technical theories, experiments, and demonstration research on CCS/CCUS [18].

3.3.1. Foundation of the United Enterprise

In 2006, under the leadership of The Economy, Trade, and Industry Ministry, 37 enterprises from oil and gas, electrical and steel-making industries established a united company named Japan CCS [33] (Figure 3). In 2012, the company was authorized by the ministry to launch a demonstrative project in Hokkaido [34]. The project consists of two phases, taking eight years to store 300 thousand tons of CO₂. In 2014, another project was launched, when the company was authorized by the Ministry of Economy, Trade and Industry and the Ministry of Environment to evaluate the potential of offshore CCS. As a part of the project, geological survey was conducted in 10 of Japan’s offshore areas. The purpose of these geological surveys is to find a place where 100 million tons of carbon dioxide can be stored. In 2019, Japan CCS successfully stored 300 thousand tons of CO₂, in a location 4 km off the Hokkaido coastline with a depth of 1000 to 2500 m (Figure 3).

3.3.2. Found the CCS Research Association

In 2016, Japan established the GCS (Carbon Dioxide Geological Storage Technology Research Association) with the support of the non-profit organization REIT (Earth Environment Industry Technology Research Institute), aiming to integrate technology and reduce costs. The association consists of eight renowned companies and scientific research institutes, namely Japan Applied Geology Corporation, International Petroleum Development Corporation, Nippon Oil Corporation, and the Earth Environment Innovation Technology Institute (Group). The GCS framework encompasses three projects aimed at the commercialization of CCS, namely Development on Safety Management Technologies for Large-scale CO₂ Injection and Storage, Technologies for Efficient Pressure Management and Utilization of Large-scale Reservoirs, and Environment Setting for CCS Deployment and Standard Development. The research themes encompass geological modeling for large-scale reservoirs, reservoir evaluation of long-term CO₂ monitoring technologies by applying enhanced CO₂ dissolution technique for storage efficiency improvement, and enhancement of social acceptance and compatibility with international standardization. In summary, the establishment of GCS not only makes Japan an effective promotor of the research, development, and commercial application of CCS technology, but also facilitates global recognition of Japanese CCS technology, enhances international cooperation, and fosters a substantial pool of international talents for Japan.

3.3.3. Accelerate Commercialization and International Cooperation

JOGMEC (Japan Organization for Metals & Energy Security, at Tokyo, Japan) is not only an important steward of Japan’s energy and resource security, but is also an important supporter and loyal practitioner of the Japanese government’s efforts to tackle climate challenge, promote energy structure transformation, develop CCS technology, and expand an international cooperation network. It introduced several initiatives, including a sustainable development initiative (2018), a technology business strategy for a low-carbon society (2020) and a carbon neutrality Initiative (2021) [35]. In working in the framework of the carbon neutrality initiative, JOGMEC takes CCS as one of six act plans, alongside fossil fuel development and decarbonization and geothermal energy development [36]. To promote activities aimed at contributing to the achievement of a carbon neutral society, JOGMEC established the Carbon Neutral Promotion Headquarters on 1 April 2021 [37]. The President and the Executive Vice President of JOGMEC are also Executive Managing Director and Managing Director of Carbon Neutral Promotion Headquarters, respectively. The specific activities carried out by JOGMEC to support CCS include: (1) CO₂ injection simulation analysis for aquifers (strata filled with stratum water). (2) CCS-suitable site survey support utilizing data from geological surveys and 3D geophysical exploration vessels. (3) Strengthening cooperation with oil- and gas-producing countries. (4) Active involvement in and contribution to the construction of evaluation methods, methodologies, and certification frameworks for CO₂ reduction [38]. By cooperating with Malaysia, JOGMEC successfully helped Japanese companies obtain suitable offshore CCS sites overseas [39].

4. Offshore CCS Status in China

China also takes CCS technology seriously, as it has made tremendous efforts in research and launching pilot projects and the commercialization process. It has successfully implemented pilot tests, such as CO₂ deep geological storage demonstration project in Ordos, Inner Mongolia andCO₂ flooding and geological storage in Cainan Oilfield, Xinjiang. In terms of Offshore CCS, Chinese scientists have also carried out a lot of work.

In 2010, China Geological Survey (CGS) implemented the National Carbon Dioxide Storage Potential Evaluation and Demonstration Project, which evaluated the CCS potential and suitability of 18 offshore sedimentary basins. The results showed that the offshore CCS potential can reach 1.5 trillion tons of CO₂ [40,41,42]. In August 2021, CNOOC (China National Offshore Oil Corporation at Beijing, China) implemented the first offshore CCS demonstration project in the Zhujiangkou Basin of the South China Sea, and stored CO₂ associated with the development of the Enping 15-1 oilfield group at a depth of 800–900 m below the seabed. It is estimated that about 300,000 tons of CO₂ can be stored each year, and more than 1.46 million tons of CO₂ can be stored in total. Thanks to the concerted efforts of academic institutes such as CGS and CNOOC, a lot of difficulties in CCS have been overcome. However, there is still a long way to go before we can get offshore CCS commercialized.

Although China has huge offshore CCS potential, the accuracy of the evaluation is low. Almost all the evaluation parameters and related data in 2012 came from public information, and the evaluation accuracy was far away from the engineering level, which could not meet the needs of the actual work of CCS. In contrast, the United States’ program Mid-Atlantic U.S. Offshore Carbon Storage Resource Assessment used nearly 2300 core samples, 300 km of logging data and 4000 km of seismic data. It took almost three years to complete the potential evaluation.

Meanwhile, compared with developed countries that have realized commercialization, offshore CCS research in China started very late, and the development of various technical is unbalanced at present. There is still a big gap between large-scale and whole-process demonstration and application. According to the China CCUS Report (2023), China has made significant progress in CCS technology in recent years, including large-scale carbon dioxide capture, pipeline transportation, utilization and storage system design capabilities. However, there is still an imbalance in the development of these aspects and a gap remains for large-scale commercial application in the near future [43,44].

China has established the CCUS Industrial Technology Innovation Strategic Alliance to enhance the domestic research and development of CCS technology, construct demonstration platforms, and promote industry-university-research collaboration. Extensive cooperation has been conducted with international organizations, such as the International Energy Agency (IEA) and the Carbon Capture Leaders Forum (CSLF), as well as with countries and regions, including the European Union, the United States, Australia, Canada, and Italy, for multi-level bilateral scientific and technological cooperation on CCS [45] (Qin et al., 2020). In June 2022, Guangdong Provincial Development and Reform Commission, CNOOC, Shell Group and ExxonMobil signed a memorandum of understanding for the Daya Bay Area CCUS Cluster Project to capture and store over 10 million tons of CO₂ annually. Sinopec also signed a cooperation agreement with Shell, China Baowu and BASF in November 2022 to launch China’s first open CCS project that will collect CO₂ from industrial enterprises along the Yangtze River for transport via tank ships to CO₂ receiving stations before being transported through pipelines to land or sea storage points. Tencent Group has announced its goal of becoming carbon neutral by 2030, and is working with the Icelandic company Carbfix on a demonstration project for rapid CO₂ underground basalt mineralization storage [44].

5. Discussion

5.1. Chanllenges

Although CCS technology is being implemented in developed countries, it is still in the early or demonstration stage. Globally, this emerging technology has promising development prospects, but there are challenges in promoting CCS, particularly regarding investment costs, laws and regulations, and operational safety. Currently, CCS applications are mainly focused on the oil and gas sector. The estimated average cost for commercial carbon dioxide operation is around $70 per tonne, making it expensive to operate and limited by capture technology [46,47,48].

Currently, the overall economic viability of the entire CCS process is suboptimal, and numerous unknown challenges persist in implementing large-scale and integrated CCS projects. The exorbitant construction costs may render them unaffordable for major enterprises, while securing technical financing remains arduous and energy consumption levels remain high, posing difficulties for sustained enterprise operations [49]. The laws and regulations on CCS are currently inadequate. Only Australia and Norway have enacted legislation to hold the government accountable for long-term legal responsibility, while other countries lack a comprehensive framework for implementing CCS [50].

The presence of carbon dioxide in the formation can lead to physical and chemical reactions with surrounding rock, groundwater, magmatic hydrothermal systems, and other media, thereby compromising the stability of the formation. Long-term storage may directly result in surface deformation, seismic activity induction, acidification of water quality and soil, dissolution of minerals within the formation, alterations in micro-ecological environments and regional air composition changes. Indirectly, these effects can pose risks to local human populations, as well as animals and plants [51]. The transportation and storage of carbon dioxide also pose a potential risk of leakage, which can have severe implications for human health, as well as the growth and development of animals and plants. Additionally, there may be a time delay in monitoring carbon dioxide leakage, due to technical challenges [51,52].

Despite the rapid development of CCUS technology in China, it still faces challenges, including high application costs, ineffective business models, insufficient incentives and regulatory measures, difficulties in matching source and sink, and a distance from large-scale commercial operation [18,24,44].

5.2. Suggestions

Offshore CCS research is an important field for achieving the goal of carbon neutrality, promoting the transformation and development of geological work, as well as helping to make remaining technology competitive. The British Geological Survey, for example, has become the world’s leading CCS research institute through research such as carbon storage experiments in the North Sea, and is an important driver of CCS technology development in the European Union. China’s institutes should also grasp the strategic opportunity, deploy, and take the initiative as soon as possible.

(1) Launch a new round of resource potential evaluation. After years of deployment, institutes like CGS have carried out a lot of geological survey work offshore, and have the foundation and capability to carry out offshore CCS research. A new round of resource potential investigation and evaluation should be launched as soon as possible to find out the resource base and build a national CO₂ geological storage system to support the implementation of regional planning and national projects.

(2) Promote the integration of, and collaborative research by, relevant institutions. Fully rely on geological survey and marine scientific research, promote cross-department, cross-field and whole-chain collaborative research, and carry out research on reservoir characterization, 3D modeling, seismic monitoring, standard system, marine environment, etc., and take the lead in becoming the main force and pioneer of domestic offshore CCS. When the time is ripe, it may be productive to apply to start the offshore CCS national demonstration project. Simultaneously, China should enhance collaboration on climate change with the EU, the US, the UK, and Australia to facilitate the advancement of low-carbon technologies and industries. Enhance the establishment of a comprehensive CCS knowledge system, facilitating collaborative research and development as well as knowledge sharing within the frameworks of IEA, GCCSI, CSLF, Clean Energy Ministerial (CEM), and Innovation Mission Ministerial (MI). Moreover, strengthen bilateral technical cooperation on CCUS by promoting technology exchange and transfer to expedite the research and development cycle.

(3) Conduct research on offshore CCS industrial and green financial policies. According to the US Academy of Sciences and other institutes, China needs to invest at least 100 trillion RMB to achieve the goal of “carbon neutrality”. In the face of such huge investment requirements, government funds can only cover a small part, so it is necessary to establish and improve the green financial policy system, and give play to the leadership role of enterprises in achieving ‘carbon neutrality’. Therefore, institutes should carry out much more research on offshore CCS industrial and green financial policies, and try to offer scientific support for governments, helping them to introduce corresponding technical, fiscal and tax policies.

6. Conclusions

In this paper the development status of offshore CCS in America, Europe and Japan is described and the main experience for their success is generalized. China has huge offshore CCS potential; however, compared with these countries, there is still a lot of work to do, such as to improve the accuracy of the potential evaluation, and make offshore CCS commercialized. On this basis, we suggest that China’s institutes, like China Geological Survey, should launch a new round of offshore CCS potential evaluation to reduce field risks, tackle the key scientific and technical problems of integrative and collaborative research, and carry out more research on offshore CCS industrial and green financial policies.