【Haichuan New Energy】I’m blown away! Developing electric vehicles involves such a major strategy behind it!

By Hu Yongshun, reporter from Outlook News Weekly. China aims to reach its peak carbon emissions by 2030 and achieve carbon neutrality by 2060, and there is consensus among all parties on the need to accelerate the development of new energy sources. New energy refers to various forms of energy other than traditional energy sources, such as solar energy, geothermal energy, wind energy, ocean energy, and biomass energy. The new energy system encompasses the entire chain of energy production, conversion, transmission, and distribution at the end-user level. In the view of Ouyang Minggao, an academician of the Chinese Academy of Sciences and professor at the School of Vehicle and Transportation Engineering at Tsinghua University, the new energy revolution has five key aspects: the transition from traditional fossil fuels to renewable energy sources, particularly the large-scale use of solar and wind power ； Energy is shifting from centralized to distributed ； Using technologies such as hydrogen and batteries to store intermittent energy sources ； Develop the energy internet ； Electric vehicles have become endpoints for energy consumption and storage. Academician Ouyang Minggao said in an exclusive interview with a reporter from Outlook News Weekly that current new energy generation technologies such as photovoltaic and wind power are relatively mature, and the cost of power generation has decreased significantly, making it possible to deploy them on a large scale. However, since new energy generation is characterized by volatility, intermittency, and randomness, it must be combined with energy storage in order to serve as a main source of energy supply. He believes that new energy vehicles, represented by pure electric vehicles, can serve as large-scale, low-cost, and highly safe distributed energy storage systems with short deployment times in our country, providing an opportunity to overcome the bottlenecks in the development of new energy technologies.

Electric vehicles will change the way energy is used. Outlook: Why do you think batteries and electric vehicles can play an important role in new energy power systems? Ouyang Minggao: First of all, it is important to understand that the battery power system of electric vehicles is essentially a type of energy storage system. Comparing traditional power systems with new energy power systems, in a traditional power system, power plants convert primary energy into electrical energy, which is then transmitted, transformed, and distributed to end-users, thus completing the entire process from production to use of electrical energy. In this process, energy transmission is a one-way flow from centralized power generation sites to end-users, featuring the basic characteristic of \"the source following the load\". In new energy power systems, the power generation from photovoltaic panels and wind turbines varies over time and with the seasons, and electricity demand also changes. This requires flexible interactive regulation among the sources, grid, load, and storage systems. Therefore, to address the intermittency and volatility of new energy power generation and ensure the stable operation of the power grid, it is essential to install energy storage systems. Looking at current energy storage systems, based on their power capacity and storage duration, batteries and hydrogen energy are suitable respectively for short-term, small-scale energy storage needs as well as long-term, large-scale storage needs. They complement each other well and together constitute the mainstream energy storage methods of the future. At present, about 85% of the installed capacity for electrochemical energy storage in China is made up of lithium-ion batteries, with an energy storage cost of 0.6–0.9 yuan per kilowatt-hour; of this amount, around 67% corresponds to the cost of the batteries. Although lithium-ion batteries are not more cost-effective compared to pumped hydro storage, which has a cost of 0.2–0.25 yuan per kilowatt-hour, pumped hydro storage is subject to significant geographical constraints and is therefore difficult to implement. The cost of producing hydrogen through water electrolysis includes electricity costs, fixed costs, maintenance costs, and water fees, resulting in relatively high expenses. Therefore, electric vehicles and their battery-powered systems represent a relatively ideal method of energy storage at present. Over the past two decades, Chinese researchers have made breakthroughs in the technical platform for new energy vehicle power systems, as well as in the three core technologies of batteries, motors, and electronic control systems. Over the past decade, lithium-ion batteries have been widely used in electric vehicles. Pure electric vehicles, represented by lithium-ion batteries, will play an important role in the storage of new energy electricity. Estimates suggest that by 2040, the number of electric vehicles in China will reach 300 million. Assuming an average battery capacity of 65 kilowatt-hours per vehicle, the total energy storage capacity of these vehicles across the country will be around 20 billion kilowatt-hours, which is roughly equivalent to the total amount of electricity consumed in China on a daily basis. It can be said that electric vehicles are changing the way humans utilize energy and driving the advent of a new energy revolution.

Battery technology is becoming increasingly mature. Outlook: From this perspective, for pure electric vehicles to become an important tool for distributed energy storage in the future, batteries are the key. What is the current development level of the in-vehicle battery industry in our country? Ouyang Minggao: At present, the scale and level of China’s in-vehicle battery industry have risen to the forefront in the world, with significant improvements in battery performance. In terms of technology, the issues related to battery range and lifespan have seen significant improvements. Data shows that the range of electric vehicles has increased from around 150 kilometers at the beginning of their adoption to an average of 500–600 kilometers, with luxury electric vehicles approaching a range of 1,000 kilometers. In terms of specific energy, which is an indicator of the energy that can be provided per unit weight or volume of a battery, it has increased threefold over the past decade, while costs have dropped by 85%. Advances have been made in technologies related to the safety of high specific energy batteries, their driving range in winter, and super-fast charging on highways; standards are being established, and these technologies are being gradually introduced and deployed. In terms of the industry, the batteries produced in our country account for about 60% to 70% of the global production capacity. Among the world’s top 10 battery manufacturers, seven are Chinese companies*, including CATL in first place and BYD in third place. In the future, there will also be a significant increase in demand for batteries along with a substantial decline in their costs. China’s current battery production capacity is only 100 million kWh; it is estimated that by 2025, the total production capacity of China’s top five lithium-ion battery manufacturers will exceed 1 billion kWh. At the same time, the cost of lithium-ion battery systems will decline rapidly. According to the \"Energy-Saving and New Energy Vehicle Technology Roadmap 2.0\" released by the Society of Automotive Engineers of China, it is expected that by 2025, the cost of lithium iron phosphate battery systems will drop to 0.5 yuan per watt-hour, with a cycle life of 5,000 to 10,000 cycles.

Outlook: What are the future directions for innovative development in battery technology? Ouyang Minggao: In the next step, efforts in battery technology development will focus on three aspects: safety, convenience, and intelligence. First, battery system safety is ensured from three aspects: the inherent safety in battery design and manufacturing, the active safety during battery use, and the passive safety in the event of a battery accident. For example, Tsinghua University has developed a systematic method for suppressing thermal runaway in high specific energy batteries, which can address the safety issues associated with the design of individual battery cells. A battery cloud control early warning platform has been developed for the entire vehicle, to provide safety monitoring during operation and issue warnings for faults. Second, strengthen research and development in fast charging technology. Electric vehicle charging modes can be divided into slow charging and fast charging. For private cars, slow charging is the best option, but when on highways or for long trips, ultra-fast charging with a power output of 120–350 kilowatts is required. In 2020, the China Electricity Council introduced a new standard for high-power fast charging – the Super Charging Standard – with full deployment of ultra-fast charging services expected by 2025. Tsinghua University has developed a lithium-free safe fast-charging technology; charging is carried out when the battery level drops to 50%, and 5 minutes of charging allows the vehicle to travel 200 kilometers. Third, adapt to the intelligent requirements of vehicle-grid interaction. In the initial stage of the spread of electric vehicles, charging was carried out in an unorganized manner; as the number of electric vehicles increased, the power grids in some large cities faced greater strain. Currently, cities such as Shenzhen and Shanghai are planning to implement orderly charging, which involves using apps to coordinate with backend scheduling systems in order to schedule battery charging during times when the grid load is low. In the future, efforts will also be made to develop Vehicle-to-Grid technology (V2G): electric vehicles will be charged when the grid load is low, and they will supply power back to the grid when the load is high, thereby helping to balance the grid load.

Building a new type of intelligent power system with vehicle-grid interaction 《Outlook》: What are the characteristics of vehicle-grid interaction technology? How feasible is it for it to help balance the load on the power grid? Ouyang Minggao: Renewable energy power generation is characterized by intermittency and randomness, while fast charging of electric vehicles can easily put strain on the power grid. Therefore, with the increase in new energy power generation and the widespread use of electric vehicles, the safe and stable operation of power grid systems will face significant challenges, making it urgent to develop a new type of intelligent power system based on new energy sources. V2G interaction refers to the ability of vehicles to both charge from the power grid and discharge energy back into it, enabling two-way connectivity. An important reason for implementing vehicle-grid interaction is that it can flatten the grid demand curve and reduce the required load power. When electric vehicles are parked, their batteries can serve as \"power banks\" for the distribution network to be developed. By connecting numerous such \"power banks\" to an intelligent aggregation platform through Internet of Things technology, a virtual high-load system can be created. This virtual heavy load can be optimized and regulated through the energy internet and artificial intelligence technologies; electric vehicles are charged during periods of low electricity demand, while they supply power back to the grid during peak demand times. Furthermore, this approach can be adapted to the characteristics of future renewable energy sources, thereby reducing the pressure on expanding the grid capacity. It is a distributed energy storage technology characterized by large scale, low cost, and high safety, and is considered an important component of new smart power systems. As the number of electric vehicles increases and market mechanisms improve, their commercial viability continues to improve. As of 2018, the EU, the United States, Japan, and other **regions had carried out more than 70 vehicle-to-grid interaction projects. In our country, vehicle-grid interaction technology and market development are still in their infancy.

Outlook: What are the prospects for the implementation of vehicle-network interaction technology in China? Ouyang Minggao: In the new type of intelligent power system featuring vehicle-grid interaction, charging infrastructure serves as the key port for energy exchange between vehicles and the grid. Charging infrastructure is classified based on charging speed and parking characteristics, and can be divided into slow-charging with parking functionality and fast-charging for immediate use. Among them, the slow charging–stop charging composite type combines charging and parking functions, and is mainly used in integrated parking and charging facilities in residential areas, corporate offices, and public transportation and logistics vehicles. Under this approach, with long parking times and a large number of vehicles connected to the network, electric vehicles hold great potential for contributing to the regulation of the load in the power grid. The existing grid standards and infrastructure can support vehicle-grid interaction services, which are also in line with the basic technical framework and operational strategies for grid operation. For example, **the power grid company carried out pilot operations at the Beijing Zhongzai Building and Renji Building for services related to the interaction between electric vehicles and commercial buildings, as well as between electric vehicles and the power grid. In the China Re Building project, electric vehicles are charged during off-peak hours at a rate of about 0.3 yuan per kilowatt-hour, and they discharge power during peak hours at a rate of 0.7 yuan per kilowatt-hour. Through valley charge peaking, car owners can earn nearly 0.4 yuan per kilowatt-hour of electricity. **The two-way charging and discharging interactive stations installed by the power grid company in the Beijing Renji Building are integrated into the peak-shaving auxiliary services of the North China power market through a smart vehicle networking platform, using an adjustable load resource aggregation approach; this is the first project in China to be included in the settlement framework for peak-shaving auxiliary services. To date, 15 provinces and municipalities across the country have established 42 vehicle-grid interaction projects and 609 vehicle-grid interaction terminals, with nearly 4,000 electric vehicles having participated in such interactions. Although domestic vehicle-grid interaction projects are still in the demonstration phase, as the number of electric vehicles increases and the costs associated with vehicle-grid interaction decline, this technology is expected to play a greater role in future smart power systems. According to the Energy Conservation and New Energy Vehicle Technology Roadmap 2.0, the construction of charging infrastructure is set to develop rapidly in the future; it is estimated that the number of slow-charging stations will reach 70 million by 2030 and 150 million by 2035. On this basis, the development of bidirectional interactive charging stations that enable two-way energy flow with the power grid can lay the foundation for vehicle-grid interaction.

Outlook: What are the prospects for the implementation of vehicle-network interaction technology in China? Ouyang Minggao: In the new type of intelligent power system featuring vehicle-grid interaction, charging infrastructure serves as the key port for energy exchange between vehicles and the grid. Charging infrastructure is classified based on charging speed and parking characteristics, and can be divided into slow-charging with parking functionality and fast-charging for immediate use. Among them, the slow charging–stop charging composite type combines charging and parking functions, and is mainly used in integrated parking and charging facilities in residential areas, corporate offices, and public transportation and logistics vehicles. Under this approach, with long parking times and a large number of vehicles connected to the network, electric vehicles hold great potential for contributing to the regulation of the load in the power grid. The existing grid standards and infrastructure can support vehicle-grid interaction services, which are also in line with the basic technical framework and operational strategies for grid operation. For example, **the power grid company carried out pilot operations at the Beijing Zhongzai Building and Renji Building for services related to the interaction between electric vehicles and commercial buildings, as well as between electric vehicles and the power grid. In the China Re Building project, electric vehicles are charged during off-peak hours at a rate of about 0.3 yuan per kilowatt-hour, and they discharge power during peak hours at a rate of 0.7 yuan per kilowatt-hour. Through valley charge peaking, car owners can earn nearly 0.4 yuan per kilowatt-hour of electricity. **The two-way charging and discharging interactive stations installed by the power grid company in the Beijing Renji Building are integrated into the peak-shaving auxiliary services of the North China power market through a smart vehicle networking platform, using an adjustable load resource aggregation approach; this is the first project in China to be included in the settlement framework for peak-shaving auxiliary services. To date, 15 provinces and municipalities across the country have established 42 vehicle-grid interaction projects and 609 vehicle-grid interaction terminals, with nearly 4,000 electric vehicles having participated in such interactions. Although domestic vehicle-grid interaction projects are still in the demonstration phase, as the number of electric vehicles increases and the costs associated with vehicle-grid interaction decline, this technology is expected to play a greater role in future smart power systems. According to the Energy Conservation and New Energy Vehicle Technology Roadmap 2.0, the construction of charging infrastructure is set to develop rapidly in the future; it is estimated that the number of slow-charging stations will reach 70 million by 2030 and 150 million by 2035. On this basis, the development of bidirectional interactive charging stations that enable two-way energy flow with the power grid can lay the foundation for vehicle-grid interaction.