Energy security is an overall and strategic issue related to the country's economic and social development, and is crucial to the country's prosperity and development, the improvement of people's lives, and the long-term peace and stability of society. Energy transition is the main theme of the world today and for a long time to come, and it is a complex process.
Based on the global future development goals and the national conditions of China's oil and gas industry, this paper investigates a large number of current affairs news, conference papers, and energy think tanks on global climate and energy, analyzes the development trend of the world oil and gas industry and China's domestic oil and gas security situation, and puts forward the development trend of China's oil and gas industry and the measures to cope with the challenges in the process of energy transition, so as to provide reference for the transformation decision-making of Chinese oil and gas enterprises.
1 Trends in the global oil and gas industry
In 2022, global oil and gas exploration activities recovered from a low level, with the remaining proven reserves of oil reaching 2 406.9×108 t, and the remaining proven reserves of natural gas reaching 211×1012 m3, and global oil and gas production continued to grow, with oil production reaching about 46.18×108 t, and natural gas production reaching 4.17×1012 m3. With the outbreak of the Ukraine crisis in February 2022, the global fossil energy landscape has gradually evolved into a "east-west hemisphere differentiation": in the western hemisphere, Europe has significantly increased US oil and gas imports, and European and American countries are forming a relatively stable energy supply and demand chain in the western hemisphere, while in the eastern hemisphere, the energy supply chain dominated by China, India, Russia and Middle Eastern countries has evolved into a more complex energy supply and demand chain.
1.1 The transformation of oil and gas enterprises still focuses on core competitive advantages
1.1.1 The global energy market pattern has been reshaped, and the proportion of upstream investment is low
In June 2023, the World Energy Statistical Yearbook 2023 released by the British Energy Institute pointed out that in terms of energy consumption, non-fossil energy consumption will achieve rapid growth in 2022, but fossil energy still dominates, accounting for more than 80% of primary energy consumption, continuing to occupy the main position of energy consumption, and related investment accounts for less than 40% The investment of major oil and gas companies in the world has not yet recovered to the pre-COVID level, capital expenditure is still cautious, and the proportion of upstream capital expenditure has remained below 80% since 2019 (see Figure 1). The discovery of oil and gas reserves has entered a low ebb, and the three-year average oil and gas reserve replacement rate has been below 100% since 2016.
Figure 1 Changes in the proportion of total capital expenditure and upstream capital expenditure of major international oil companies
1.1.2 The low-carbon transition strategies of major international oil companies have returned to rationality
(1) Pay attention to the pillar position of oil and gas business in the energy transition. Shell appointed a new chief executive to stabilize investments in the oil and gas business, which increased by 17%. bp plans to increase its investment in oil and gas by US$10×108 per year by 2030 and raise its oil and gas production target for 2030 from 150×104 bbl/d to 200×104 bbl/d. ExxonMobil and Cheron acquired Pioneer Natural Resources and Hess Corporation for more than $600×108 and $530×108, respectively. ExxonMobil plans to double its earnings potential in the upstream sector by 2027 compared to 2019 levels.
(2) Lowering the emission reduction target at the stage. bp lowered its carbon emission reduction target, aiming to reduce carbon emissions by 20%~30% by 2030 compared to 2019, which is 35%~40% lower than the previous target.
(3) Pay more attention to the return rate of new energy business. bp maintains its 2022 investment in the low-carbon sector with no additional investment plans, while Total Energies expects a return on equity of more than 10% in 2027.
(4) Reshape the organizational structure and develop renewable energy and oil and gas in tandem. ExxonMobil will set up a separate low-carbon division in parallel with the oil and gas business, Shell will integrate its low-carbon business with refining and chemical sales and establish a separate sales and low-carbon business to eliminate 200 low-carbon solutions jobs and merge its integrated gas and upstream businesses, and TotalEnergies and bp will both integrate low-carbon and natural gas.
1.2 CCUS attention continues to increase
1.2.1 CCUS is a fundamental technology to achieve the "dual carbon" goal
The development of the global carbon capture, utilization and storage (CCUS) industry can be divided into three stages: the exploratory stage (1952-1990), the policy-driven stage (1991-2014) and the dual-effect driven stage (starting in 2015). The global CCUS industry clusters are divided into three categories according to the types of carbon sources and carbon sinks: oil company carbon source + reservoir carbon sink group, industrial carbon source + reservoir carbon sink group, and industrial carbon source + saline aquifer carbon sink group. These three types of industrial clusters have developed in three stages of the development of the global CCUS industry.
The energy sector is the main battlefield for carbon emission reduction, and the low-carbon transformation of the petroleum industry is imperative. CCUS technology can integrate the development of the oil and gas industry with green transformation and achieve large-scale zero-emission utilization of fossil energy, which plays an irreplaceable and important role.
As of September 2023, more than 150 countries around the world have proposed carbon neutrality targets, and more and more companies have committed to achieving carbon neutrality or net-zero emissions in the coming decades. China has made great progress in CCUS technology and demonstration in recent years, PetroChina has made a multi-level layout from the institutional mechanism, theory and practice, etc., and the oilfields have actively carried out CCUS application attempts, statistics show that PetroChina's oilfields can digest about 30×108 t of carbon dioxide in combination with carbon dioxide storage displacement technology, the first million-ton CCUS project - The million-ton CCUS project of Qilu Petrochemical-Shengli Oilfield has been officially put into operation by gas injection in 2022. According to the predictions of different international research institutions, it is estimated that by 2030, the average carbon emission reduction of CCUS technology will be 4.9×108 t/a, and by 2050, the carbon emission reduction will reach 27.9×108~76×108 t/a, with an average carbon emission reduction of 46.6×108 t/a.
According to the China Carbon Capture, Utilization and Storage (CCUS) Annual Report (2021), the International Energy Agency's (IEA) Sustainable Development Scenario aims to achieve net-zero emissions globally by 2070, and CCUS has become the fourth largest contributing technology over time, accounting for 15% of cumulative emission reductions. The role of CCUS can be broadly divided into three phases: (1) before 2030, the focus will be on carbon capture in existing power plants and industrial processes, such as coal power, chemicals, fertilizers, cement, and steelmaking metallurgy, and (2) CCUS deployment will increase rapidly from 2030 to 2050, especially in the cement, steel, and chemical industries, accounting for nearly one-third of the increase in carbon capture in this phase. The deployment of biomass carbon capture and storage (BECCS) will also increase rapidly, accounting for 15%, especially in power generation and low-carbon biofuels. (3) From 2050 to 2070, carbon capture will increase by 85% compared with the previous stage, of which 45% will come from BECCS and 15% will come from direct air carbon capture technology.
1.2.2 The number of CCS projects worldwide is growing explosively, and direct air carbon capture technology is attracting attention
In November 2023, the Global Carbon Capture and Storage Institute released the "Global Carbon Capture and Storage 2023" report, which pointed out that the number of global carbon capture and storage (CCS) projects has been growing for six consecutive years, and as of July 2023, the total number of commercial CCS projects in all stages of the world has reached 392, with a total annual capture scale of 3.61×108 tons. Among them, 41 projects have been put into operation with a total annual capture scale of 4 900×104 t, 26 projects are under construction with a total annual catch scale of 3 200×104 t, and 325 projects are in the development stage with a total annual catch scale of 2.8×108 t. Global CCS projects cover a wider range of industries, and the characteristics of cluster development are more significant, and CCS infrastructure has become a new industry growth point.
Direct Air Capture (DAC) technology is strategically important for achieving carbon neutrality by capturing carbon dioxide directly from the air and storing it permanently. In June 2022, China National Petroleum Corporation (CNPC) completed the opening demonstration of "Research on Carbon Dioxide Direct Capture Technology from Air" and began to lay out the DAC field. As of September 2023, 18 DAC infrastructures are in operation in Canada, the United States, Europe and other countries and regions, and the world's first large-scale DAC plant with an annual carbon capture capacity of 100×104 tons is under construction, and is expected to be operational in the United States in 2025. Through technological innovation and project deployment demonstration, it is expected that the cost of carbon capture will be reduced to less than US$100/t.
1.3 Opportunities and challenges in energy development are intertwined
The World Energy Outlook 2023, released by the International Energy Agency (IEA) in October 2023, noted that some of the immediate pressures from the global energy crisis have eased, but energy markets, geopolitics and the global economy remain volatile, and the risk of market shocks remains persistent.
ExxonMobil's latest Global Outlook predicts that by 2050, the global population will reach 97×108 people, the size of the economy will double, energy demand will increase by 15%, the share of solar and wind energy in the global energy supply will increase to 11%, and oil and gas will still account for more than half of the world's energy supply, accounting for the main part of the global energy system (see Figure 2). However, in this scenario, global CO2 emissions from energy use would be more than twice the 2 °C target, and climate catastrophe is inevitable. At present, the pace of clean energy transformation in major global markets is gradually accelerating, and the energy transition is more focused on affordability, diversification and innovation are the best strategies to solve the problem of dependence on clean energy technologies and critical mineral supply chains.
Fig. 2 Trends in global energy demand by product and the proportion of primary energy
2 China's oil and gas security situation
China's energy self-sufficiency rate is high, and the overall energy security situation is controllable. In 2016, China's energy self-sufficiency rate was only 78.4%, and since then, it has achieved growth for six consecutive years, reaching 86.1% by 2022. In 2014, China became the world's largest oil importer, and in 2018, its dependence on foreign countries exceeded 70%, and it has remained so far. Over the past 20 years, China's oil production growth rate (1.0%) has been significantly lower than the growth rate of consumption (5.8%), and in 2007, China became a net importer of natural gas, and in 2018, its dependence on foreign countries exceeded 40%, and has remained so since (see Figure 3). Both natural gas production and consumption grew by double digits, but production growth (10.2%) was lower than consumption growth (13.9%).
Fig. 3 Statistics of China's oil and gas production, consumption, and external dependence from 2000 to 2022
2.1 Challenges in oil and gas field development
2.1.1 Oilfield production is facing the challenge of "two lows and two highs".
Oilfield production is facing the challenge of "two lows and two highs". The new proved reserves are mainly low permeability, ultra-low permeability and tight oil reserves, with low grade and low oil recovery, and the recovery rate has decreased from 18.8% in 2010 to 15% in 2021. The comprehensive water cut of the developed oilfields is as high as 89.1%, and the recovery degree of recoverable reserves is as high as 82.9%, which makes it increasingly difficult to further tap the potential and stabilize production.
2.1.2 Some major gas fields have entered the decreasing stage, and unconventional gas is decreasing rapidly as the main body of production increase
Some of the main gas fields have entered the decreasing stage, and unconventional gas is decreasing rapidly as the main body of production increase. The load factor has remained high year after year, and some gas fields have seen water in advance, which affects the recovery rate and stable production life, and the production decline has increased.
Fig.4 Schematic diagram of decreasing production of tight gas and shale gas
2.2 The proportion of oil and gas import channels is high
China's oil and gas imports account for a small proportion of onshore channels. The Northeast, Northwest and Southwest oil and gas corridors have an annual transportation capacity of 7 300×104 tons of crude oil and 1 050×108 m3 of natural gas. In 2021, onshore crude oil and natural gas imports were about 5 000×104 t and 591×108 m3, accounting for 10% and 35% of the total imports, respectively. Sea lanes are the main channel for China's oil and gas imports and play a pivotal role in China's economic development. Currently, about 80% of oil imports are transported through key seas such as the Indian Ocean, the Strait of Malacca and the South China Sea. Therefore, if the sea oil corridor is threatened, it will have a huge impact on the Chinese economy. In March 2021, the Panamanian-flagged freighter "Ever Given" ran aground in the Suez Canal, blocking the channel of the canal for nearly 6 days, causing huge losses to ships waiting for navigation. In the summer of 2023, the continuous drought caused the water level of the Panama Canal, one of the world's major maritime trade routes, to be low and had to be restricted for a long time, affecting the global shipping industry.
2.3 Oil and gas reserves need to be improved
Compared with developed countries in Europe and the United States, the construction of China's oil and gas resource reserve system started late. In the complex international context, the shortcomings of reserve support are prominent. (1) Natural gas storage capacity is seriously insufficient. In recent years, China's natural gas industry has developed rapidly, and natural gas consumption has continued to grow rapidly, increasing its importance in the national energy system. At the same time, problems such as lagging gas storage infrastructure construction and insufficient reserve capacity have become prominent, which have become prominent shortcomings restricting the safe and stable supply of natural gas and the healthy development of the industry. The working gas volume of underground gas storage accounts for about 5.2% of natural gas consumption, far lower than the level of more than 15% in developed countries in Europe and the United States. (2) The elasticity of oil reserves is insufficient, although the oil reserve capacity of more than 100 days of net imports has been built, the reserves are still insufficient, resulting in the weak ability to participate in market regulation and the insufficient ability to guarantee emergency supply. (3) The spatial distribution and reserve mode of the reserve base also need to be optimized, the spatial distribution of oil reserves is uneven, the main category of reserves and the reserve mode are single, mainly above-ground storage tanks, supplemented by groundwater sealed caverns, and the construction cost of above-ground storage tanks is high, the area is large, and the safety risk is high.
3 Development trend of China's oil and gas industry
In July 2018, General Secretary Xi Jinping issued important instructions and instructions, calling for "vigorously improving domestic oil and gas exploration and development, and striving to ensure national energy security". In order to thoroughly implement the spirit of General Secretary Xi's important instructions and intensify China's domestic oil and gas exploration and development, important backbone enterprises and oil and gas production and supply enterprises have made hard efforts in oil and gas and engineering technology, and achieved remarkable results, striving for the safety red line of oil and gas dependence on foreign countries not exceeding 70% and 50% respectively.
3.1 Main dimensions of future development of oil and gas
China's oil and gas industry presents a development trend of "three dimensions".
(1) 10,000 meters depth. The depth of onshore exploration is 10,000 meters, from less than 8 000 m to 10,000 m ultra-deep depth, and from less than 1 500 m to 3 000 m at sea. In 2021, 60% of the world's large and medium-sized oil and gas discoveries were offshore oil and gas fields with a water depth of more than 1 500 m, indicating great potential for ultra-deepwater oil and gas exploration and development. However, the characteristic fluid state of 10,000-meter-level ultra-deep oil and gas reservoirs has exceeded the scope of scientific knowledge, which has brought new tests to drilling and completion technology, high-temperature and high-pressure resistant tools, etc.
(2) Nanoscale. The oil and gas reservoir space extends from the micrometer scale to the nanometer scale. At present, most of the increase in oil and gas development in China comes from unconventional fields, and the pore scale is usually nanoscale. Gulong shale oil is a hot spot in Daqing Oilfield in the past two years, and a large number of nanopores and nanofractures have developed in shale oil reservoirs in Songliao Basin. The preliminary results show that the diameter of nanopores in Gulong shale reservoir is mainly 10~50 nm, and the median value is 20~30 nm, and the phase state and basic physical state have changed significantly, which brings major challenges. At present, a major breakthrough has been made in continental shale oil technology, and China's continental shale oil revolution has gradually become a prairie fire.
(3) Centennial span. With the support of the new generation of oil and gas fields with greatly enhanced oil recovery technology, the old oil and gas fields are moving towards a century-old construction and entering the "post-reservoir" stage. China's high water cut old oilfield has produced geological reserves of 255.7×108 t, the current average recovery degree is 25.6%, of which Daqing Changyuan more than 50%, the difficulty is increasing, the "secondary development" theory formed in the early stage of research has guided the practice of oilfield oil recovery, but the mechanism of greatly improving oil recovery under the limit condition of water cut of nearly 98% in the old oilfield is not well understood, and the construction of "century-old oilfield" will rely on technological innovation to greatly improve oil recovery. In order to improve oil recovery, the enhanced oil recovery technology in high water-cut oilfields is developing in the direction of refinement and intelligence, and the quadruple oil recovery technology with nanotechnology as the core provides a new way for the development of oil and gas fields through the application of new materials such as nano.
3.2 Domestic production: unleash the potential of "two deep, one non-old and one old" to increase reserves and production
The new generation of engineering technology and equipment helps oil companies improve the life of deep-ground, deep-sea, unconventional oil and gas fields and old oil and gas fields, and release the potential of "two deep, one non-old and one old" to increase reserves and production.
(1) China's deep and ultra-deep oil and gas resources reached 671×108 TOE, accounting for 34% of the total oil and gas resources in China, and have become the main position of China's major onshore oil and gas discoveries. Among them, deep oil resources account for 26% of the total resources, but the detection rate is only 11%~15%, and deep natural gas resources account for 48% of the total resources, and the detection rate is 20%~28%. Deep and ultra-deep oil and gas are important areas and main battlefields for increasing reserves and production in the future, and it is necessary to accelerate the establishment of independent deep-ultra-deep oil and gas theory, equipment and technical systems.
(2) In December 2023, the China Marine Energy Development Report 2023 released by the Energy Economics Research Institute of CNOOC Group predicts that China's offshore oil and gas production is expected to reach a new high in 2023. Among them, the offshore crude oil production was 6 220×104 t, with an increase of about 360×104 t, accounting for more than 60% of the increase in national crude oil production for four consecutive years, and the offshore natural gas production was about 238×108 m3, with an increase of 19×108 m3, accounting for about 15% of the increase in national natural gas production. China's offshore oil and gas recoverable resources account for 33% and 35% of the country's total resources, respectively. The theory and technology of accumulation in large and medium-sized oil and gas fields in deep offshore water, the research on the hydrocarbon formation, storage and accumulation mechanism of deep-water oil and gas in offshore water, the production of heavy oil and low permeability reserves in offshore and the continuous large-scale increase in reserves and production of offshore oil and gas, and the technology and equipment of deep-sea independent exploration and development will help the offshore oil and gas exploration and development to achieve new results.
(3) China's unconventional crude oil production accounts for about 10% of the total output, and unconventional natural gas production accounts for about 40% of the total output. In recent years, China has made strategic breakthroughs in unconventional oil and gas exploration and development, and has the potential to lead the continental shale oil revolution.
(4) At present, the developed old oilfields with a water cut of more than 70% in China account for about 70% of the remaining recoverable reserves and about 70% of the production, which is the ballast stone of crude oil production.
3.3 International cooperation: Deepen energy cooperation in key regions of the Belt and Road Initiative
On October 18, 2023, General Secretary Xi Jinping attended the opening ceremony of the 3rd Belt and Road Forum for International Cooperation and delivered a keynote speech, pointing out the direction for deepening energy cooperation along the Belt and Road and welcoming the new development of the Belt and Road Initiative with higher quality and higher level. Enterprises and institutions in the energy field should forge ahead and take responsibility, deepen energy cooperation in key areas of the "Belt and Road", strengthen policy communication and institutional guarantees with major energy resource countries in terms of investment protection, taxation, finance, access, standards, public opinion environment, etc., actively build a sound and effective risk management and control system, and effectively prevent various risks such as economy, security, exchange rate, policy, and law in cooperation; Multilateral cooperation and coordination mechanisms to ensure the long-term safe and stable operation of oil and gas projects and cross-border pipelines. We will build a stable and safe trade settlement path, create a group of stable and reliable strategic partners, strive for high-quality oil and gas projects, master deep-sea oil and gas exploration and development and liquefied natural gas (LNG) liquefaction technology, and improve international operation capabilities. Accelerate the promotion of energy shipping "national ship and national insurance", and establish a shipping emergency guarantee plan. We will work together to build a global energy interconnection, and contribute to promoting the green and low-carbon transformation of the world's energy and high-quality Belt and Road cooperation. Figure 5 shows the oil and gas equity production of Chinese oil companies in countries along the "Belt and Road" from 2003 to 2022.
Fig. 5 Oil and gas equity production of Chinese oil companies in countries along the Belt and Road
3.4 Infrastructure: Expand oil and gas reserve capacity and improve pipeline network layout
In recent years, China's oil and gas reserve capacity has been greatly improved, the construction of the third phase of the national strategic reserve has been completed, the natural gas production, supply, storage and marketing system has been continuously improved, and the scale of underground gas storage and liquefied natural gas (LNG) storage tanks has continued to increase, accounting for about 7.5% of annual consumption, but it is still necessary to continue to improve the scale of oil and gas reserves and enrich the storage methods.
Carry out the national underground storage planning, establish more underground space reserve facilities, accelerate the overcoming of technical challenges, break through the large-scale oil storage technology of underground space (salt caverns, water-sealed caverns, aquifers, depleted oil and gas reservoirs and abandoned pits, etc.), salt caverns and aquifer gas storage construction technologies, effectively use underground storage space, and strive to achieve 90 days of oil reserve capacity in 2030, with a reserve scale of 1.8×108~2×108 t, and a natural gas reserve capacity of 1 000×108 m3, of which the inland reserve capacity is 600×108~700×108 m3, and the coastal LNG receiving capacity is 300×108~400×108 m3;
3.5 Digital intelligence empowerment: Establish a systematic and intelligent risk management and decision support system
The integrated development of the energy industry and digital technology is an important engine to promote the upgrading of China's energy industry base and the modernization of the industrial chain in the new era. Establishing a systematic and intelligent risk management and decision support system is the top priority at present. These include deepening the research on risk factors and influencing mechanisms, establishing an intelligent monitoring and early warning platform, and building a complete risk "identification-evaluation-early warning-response-improvement" decision support system, taking into account the short-term risk assessment at the production and operation level and the medium- and long-term risk assessment at the strategic planning level, planning in advance and planning ahead of time, and promoting the digital and intelligent transformation of the entire industry chain to achieve both safety and efficiency improvement.
3.6 Low-carbon development: Vigorously develop the CCUS industry chain
Chinese oil and gas companies have the greatest advantage in carrying out CCUS business, the oil and gas industry has a long industrial chain and relatively concentrated carbon emissions, so it is urgent to transition to low-carbon and integrate into the overall development of China's new energy system.
In November 2023, China and the United States jointly issued the Sunshine Land Statement on Strengthening Cooperation to Address the Climate Crisis, aiming to promote at least five large-scale CCUS cooperation projects in the fields of industry and energy by 2030. According to the Annual Report on Carbon Dioxide Capture, Utilization and Storage in China 2023, China's theoretical carbon dioxide geological storage capacity is about 1.21×1012~4.13×1012 t, mainly including geological structures such as saline aquifers and oil and gas fields. The proven oil fields in China can store about 200×108 t of carbon dioxide, of which the suitable reservoir capacity is about 50×108 t, the proven gas reservoir can finally store about 150×108 t of carbon dioxide, and the deep saline aquifer has a storage capacity of 0.16×1012~2.42×1012 t, and the large and medium-sized sedimentary basins such as the Tarim Basin, Ordos Basin, Songliao Basin, Bohai Bay Basin, and Pearl River Estuary Basin have large storage capacity and relatively good storage conditions.
It is estimated that by 2050, CCS/CCUS will achieve carbon emission reductions of about 10×108 t/a. At present, the transformation of the oil and gas industry has entered a period of "extreme pulling" and is facing a difficult choice. The industry agrees that oil and gas and new energy are established first and then broken, and integrated development. Give full play to the advantages of the integration of oil and gas and new energy, resources and technical teams, vigorously develop new energy businesses such as geothermal, wind and solar energy, and achieve high-quality development of enterprises. There are abundant application scenarios for integrated energy in oil and gas production, such as distributed smart grids, source-grid-load-storage multi-energy complementarity, and "oil-gas-heat-power-hydrogen" co-generation, which can expand clean, low-carbon and efficient comprehensive energy services.
4 Conclusion
(1) The opportunities and challenges of global energy development are intertwined. The Ukraine crisis has led to a profound adjustment of the global energy landscape, and major oil and gas companies around the world have given up radical transformation and returned to oil and gas fundamentals. The industry's attention to CCUS has increased again, and it is recognized as a backstop technology for fossil fuels to achieve carbon peak and carbon neutrality.
(2) China's energy shortcomings are mainly concentrated in the oil and gas sector, and the core of energy security is oil and gas security. China is the world's largest importer of oil and gas, with a high dependence on oil and gas imports, a high proportion of import channels at sea, and high security risks. Oilfield production is facing the challenge of "two lows and two highs"; some major gas fields have entered a decreasing stage, and unconventional gas as the main body of production increase is decreasing rapidly; the construction of oil and gas reserve system started late, and the reserve capacity needs to be improved.
(3) The development of China's oil and gas industry needs to focus on five aspects: unleashing the potential of "two deep, one non-old and one old" to increase reserves and production, and enhancing exploration and development, deepening energy cooperation in key areas of the "Belt and Road", expanding oil and gas reserve capacity, optimizing pipeline network layout, improving infrastructure, and improving energy emergency response capabilities, establishing a systematic and intelligent risk management and decision support system to achieve digital and intelligent empowerment, vigorously developing low-carbon industries, and promoting the integrated development of oil and gas and new energy.
Source: World Petroleum Industry
Authors: Sun Longde, Zhang Pengcheng, Jiang Hang, Wang Zugang
Editor: Hu Liang
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