Future grid needs to meet two alternative requirements

The power grid is the most important support platform for the global energy internet. What changes will happen in the future? Our correspondent interviewed Zhang Yunzhou, president of the State Grid Energy Research Institute, and asked him to interpret it from the perspective of development orientation and technological innovation. The development trend in the energy interconnection landscape. In the interview, Zhang Yunzhou repeatedly mentioned the characteristics of equality, openness, and diversity in the global energy internet. It can be seen that these DNAs that belong to the Internet will roll in the blood of energy.

“State Grid”: Recently, “Energy Internet” has become the most popular concept in the energy industry. The Internet has penetrated into all aspects of the energy field, but it is exciting and challenging to raise the energy Internet to the global level. The idea is to realize this idea. How will the positioning of the power grid change?

Zhang Yunzhou: Under the global energy internet concept, the development of the power grid will gradually change.

Looking at the development orientation of the power grid needs to be based on energy development trends and laws, and consider the development direction and focus of the power grid from the perspective of solving the problem of sustainable energy development. Over the past thousands of years, the energy development process has presented three trends: the development of the energy structure from high-carbon to low-carbon, the development of energy use from inefficient to efficient, and the development of energy allocation from local equilibrium to large-scale optimization. The practice in recent years shows that these trends are more obvious.

First of all, the global challenge of addressing climate change forces the energy revolution to accelerate. The long-term development and utilization of fossil energy has led to an increasingly serious problem of global warming and ecological environmental destruction. The development of low-carbon energy and decarbonization of energy has become increasingly urgent, and the development of clean energy is urgently needed. In 2014, the global temperature reached a record high, and it was the third time in nearly 10 years that it had set a new record. In this century, the global temperature has risen (pre-industrialization) within 2 degrees.

Second, electrical energy substitution is an important way to improve energy efficiency. From the perspective of primary energy utilization efficiency, the space for improvement of fossil energy efficiency has been getting smaller and smaller, while the clean energy power generation efficiency of wind energy, solar energy, etc. has benefited from technological innovation is significantly improved; from the perspective of end-use energy efficiency, the efficiency of terminal energy utilization is far Higher than other fossil energy direct use efficiency. Electricity is not only an important carrier for the use of clean energy, but also helps to improve the overall efficiency of energy.

Third, the efficient use of clean energy depends on a wide range of resource allocation. The main use of clean energy is to convert electricity into electricity on the spot. Clean energy-rich regions are often far away from load centers. Accelerating the development of clean energy will inevitably require large-scale optimization of power distribution. The large-scale development of renewable energy resources in recent years is changing the traditional concept of balanced development of electricity on the ground.

Therefore, in the future, the power grid must meet the requirements of “two alternatives” and assume a broader role in resource allocation. For the development of power grids, overall research should be conducted in consideration of domestic energy supply and demand, consideration of multinational energy supply and demand, consideration of inter-continental global energy supply and demand patterns, and identification of the global energy internet as the development direction, and the protection of domestic power supply security and economy. Sex, adapting to the development needs of the country’s economic and social growth.

To meet the requirements of the "two alternatives" and adapt to the changes in the future energy supply, what form will the grid development take?

Zhang Yunzhou: With the continuous development of power transmission technology and the gradual maturity of power grid intelligent technology, the power grid will gradually expand and vertically penetrate, and gradually form an open giant energy deployment platform.

The so-called horizontal expansion refers to the grid's access to large-scale renewable energy sources, which needs to be balanced in a large area. The volatility and randomness of renewable energy power generation output determines that the large-scale development of power grids will increase the demand for power grid absorption. It requires the establishment of a strong UHV backbone network grid to achieve domestic networking, cross-border, and inter-continental networking, making clean energy It can be developed and used efficiently on a global scale.

Longitudinal penetration refers to the organic combination of a strong UHV backbone backbone and a ubiquitous smart grid. To meet the requirements of ubiquitous distributed energy on-site development, flexible access, and efficient configuration and utilization of power grids at various voltage levels, but also to adapt to large-scale renewable energy power output or access requirements, through various levels of voltage networks , Efficient configuration to the user side, and with continuous upgrading of smart grid technology as a means to achieve a high degree of integration of the voltage level grid.

On the open platform, the power grid will become an intelligent energy allocation platform. It will be fair and open to various types of power sources such as centralized and distributed, and all types of users, so that different entities can enter the market on an equal footing. Equity in choosing trading objects and realizing energy and information The fair exchange of services and the open sharing of network resources; meet the two-way interaction between energy producers and consumers, support diversified electricity demand, and achieve the optimal use of electricity and other energy through intelligent terminal equipment connections.

Overall, in the future, the power grid will exhibit the interconnection and interconnection of backbone grids with UHV technology as the main body. The voltage grids of various voltage levels have a clear structure and clear functions. The system is highly intelligent and reliable, users share resources equally, and the global development of clean energy is fully utilized. Global use of the global configuration platform.

“State Grid”: How should the global energy internet gradually advance? What kind of characteristics will the energy production and consumption show on the global energy internet resource allocation platform?

Zhang Yunzhou: Building a global energy internet is an unprecedented large-scale system project, which requires a long period of development. Due to the influence and constraints of resources, technology, economics, and political conditions, the construction of global energy internet needs to be advanced in ways that are easy and difficult to come by. In the areas with good networking conditions and networking requirements, priority will be given to building a global grid interconnection from point-to-face and face-to-face.

The first is the interconnection of power grids between countries in the continent. From the perspective of the development of the power grids in the world, the interconnectedness of neighboring countries and even the formation of interconnections among countries in the continent has become an important development trend. The North American interconnected power grid and the European interconnected power grid have been practiced for many years and are being scaled up. The interconnection of power grids is being promoted in Africa, the Gulf region, and South America. With the implementation of China's "One Belt and One Road" strategy, the interconnection between China's power grid and neighboring countries will also advance rapidly. In the future, with the construction and development of large-scale clean energy power generation bases, transnational interconnected power grids in the continent will accelerate development to meet the ever-expanding demand for clean energy consumption and realize the complementarity and mutual benefit of different types of power resources in different seasons, at different times, and in different countries. , improve energy system efficiency and economy.

The second step is to gradually promote inter-continental interconnection. Inter-continental interconnection can achieve a wider range of clean energy balance and consumption. At the same time, inter-continental interconnection has made the benefits of multi-type power resources complementarity, time difference, and season more significant. It is necessary to gradually promote inter-continental interconnection in the order of ease and difficulty.

While developing transnational and transcontinental backbone networks, it is necessary to constantly improve the ubiquitous smart grids in various countries. The national ubiquitous smart grid is a basic component of the global energy internet. It is widely connected with domestic energy bases, distributed power sources, and load centers. It is the basic guarantee for sending clean energy power generation to load centers.

In addition, an important feature of the global energy Internet is its high level of intelligence. The key to the development of intelligent development is to improve the level of intelligence in all aspects of power generation, transmission, substation, power distribution, electricity use, dispatch, and communications. Utilizing the characteristics of the ubiquitous smart grid, we can realize the on-site development and flexible access of distributed power sources. Everyone can be a producer and consumer of electricity, and ultimately achieve the equal participation of global energy Internet users.

National Grid: What key technologies are needed to achieve such a grand and complex global power system?

Zhang Yunzhou: The construction of the global energy internet is a huge system engineering. The technical part is an important foundation for its development and implementation. There are many types of technologies needed, and a great deal of technological innovation will also be brought about. In general, building a global energy internet requires key technical support in the fields of power supply, power grid, energy storage, and information and communications. The core of power supply technology is to clean power generation technologies and improve the development efficiency and economic efficiency of clean energy. The core of power grid technology is large-capacity, long-distance transmission technologies. It is necessary to continuously improve the transmission capacity, configuration capability, and economy of the power grid. The main areas include UHV AC/DC transmission technology and equipment, submarine cable technology, and large-scale power grid operation control technologies; in terms of energy storage technology, the core is the electrical energy storage technology. Energy storage technology can increase the energy storage link in the power system, which can stabilize the volatility brought by large-scale clean energy generation and access to the power grid, and improve the safety, economy, and flexibility of power grid operation. Continuously improving the economics, charging and discharging characteristics, and capacity scale of energy storage devices are the direction of energy storage technology innovation and commercialization. The core of information and communication technologies is energy and information fusion technologies. Information and communication technology is the basic support for realizing the intelligentization, interaction, and operation control of large-scale power grids, and is an important guarantee for the safe and efficient operation of the global energy Internet. To adapt to the development of the global energy Internet, the rapid growth of information and communication capacity, and the significant expansion of the scope of information communications, it is bound to put more stringent requirements on the safety, real-time, and reliability of information and communication.