"Promote clean and efficient use of energy and technological research and development, and accelerate constructionNew energy system", this year's government work report points out the development path for the next direction of energy development. How to understand the inherent meaning of the "new energy system"? How to achieve clean and efficient use of coal? A reporter from China Energy Media recently interviewed Liu Jizhen, an academician of the Chinese Academy of Engineering, professor of North China Electric Power University, and director of the National Key Laboratory of New Energy Power Systems on related issues.

"Until finding a new path, we cannot shake our attention to the dominant position of coal"

In Liu Jizhen's view, the construction of a new energy system is a practical issue that is still being explored. Factors such as whether energy supply is safe, the advancement of the "dual carbon" goal, and the technological innovation brought about by the Fourth Industrial Revolution have given the new energy system distinctive characteristics of the times. The construction of a new energy system must not only meet the direction of low-carbon development, but also serve the development of the economy and society and the country's achievement of the two centenary goals, and also serve the people's lives to improve their energy needs. "This system is complex and involves all aspects. But the most basic characteristics are very clear, which are clean, low-carbon, safe and efficient." Liu Jizhen said.

my country's primary energy endowment structure is characterized by "rich coal, poor oil, and low gas", and coal occupies a dominant position in the domestic energy structure. "Coal supports my country's energy supply. Coal cannot be judged as having an 'original sin' just because coal combustion is polluting." Liu Jizhen said.

Faced with the major issue of global warming, the global energy structure is already accelerating adjustment. To achieveClean and low-carbonmy country has been actively promoting the energy revolution andEnergy Transformation。

"At this stage, we must follow the 'establishment first and then break'. This means that before finding a new path, we cannot shake the importance of coal's dominant position. In this process, we must pay attention to the transformation of coal itself, and at the same time deeply integrate and develop coal and new energy." Liu Jizhen said: "Our basic national conditions and resource endowment determine the historic process and phased characteristics of the low-carbon transformation goal. We must look at this issue with scientific ideas and methods. Any bias and one-sidedness will cause undue losses."

"In order to promote support for new energy, nearly 100 million kilowatt coal-fired units have been resiliently transformed across the country."

How to deeply integrate coal with new energy to develop?

"At present, my country's non-coal power generation installed capacity has exceeded 1.2 billion, accounting for half of the total installed capacity. However, in terms of power generation, coal-fired power accounts for nearly 60%, while wind and solar power generation accounts for only 12%. " Liu Jizhen said.

"Traditional energy is 'primary energy can be stored and secondary energy can be controlled', while new energy is 'primary energy cannot be stored and secondary energy constraints can be controlled'." Liu Jizhen believes that according to this characteristic, to give full play to the maximum effect of new energy, thermal power must first be flexibly adjusted, relying on the regulation capabilities of the power grid to achieve multi-energy complementarity. Secondly, source and network coordination should be achieved in the power system. Again, we must make a point on the demand side to achieve supply and demand interaction. Finally, we must move towards flexibility and realize flexible power systems with smart grids and smart power generation.

"In the new energy system, multiple energy sources have their own characteristics and their own advantages and disadvantages. This is like a team, in order to achieve personal complementarity, they can develop harmoniously." Liu Jizhen made an image metaphor: "Wind and light power generation is subject to climate change, and the power generation is unstable, just like a disobedient child. As he grows up, a high proportion of power generation tasks will be pressed on his shoulders in the future, and a stable 'big brother' thermal power will be needed to provide a guarantee. Before the advancement of energy storage technology and the cost reduction, clean and efficient thermal power will still be used to play the role of a 'ballast stone'." Liu Jizhen revealed that in order to promote the support of coal-fired power for new energy, nearly 100 million kilowatts of coal-fired units across the country have been flexiblely transformed.

The energy usage mode ranges from "source moves with load", to "supply and demand interaction", and then to "load moves with source"

The way coal can be used to achieve clean utilization has always been a hot topic of focus and exploration in the industry. Liu Jizhen introduced that as the world's largest power producer, thermal power dominates. "The goal we pursue for the development of coal-fired power is always safe, clean and efficient. After decades of struggle, the core technology of coal-fired power has basically been in our own hands, and many technologies have also reached the forefront of the world, such as the research, development, manufacturing and application of million-kilowatt ultra-supercritical units."

Liu Jizhen introduced that with the help of technological advances, my country's average coal consumption of electricity and coal has dropped from nearly 400 grams/kilowatt-hour 20 years ago to about 300 grams/kilowatt-hour now. The development and application of secondary reheating, high-level layout, ultra-clean emissions, CCUS and other technologies in coal-fired power provides an effective way for clean and efficient utilization of coal. In recent years, more than 90% of coal-fired units' smoke, sulfur dioxide and nitrogen oxide emission indicators have passed clean transformation, which are far lower than the national emission standards, and some are even better than the gas emission indicators.

Now, many units are actively exploring technical paths to solve deep pollution and the capture of carbon dioxide. "For example, the research and demonstration project of the 500,000 tons/year carbon dioxide capture and resource utilization of energy utilization technology of the State Energy Group Jiangsu Taizhou Power Plant is the largest CCUS project under construction in China. It can completely solve the carbon emission reduction problem of large thermal power plants." Liu Jizhen said, "After this project is completed, it will achieve a carbon dioxide capture rate of more than 90%, an annual capture volume of 500,000 tons, and the overall performance indicators reach the international leading level. It can accumulate experience to support the low-carbon transformation of thermal power plants and have a general demonstration effect."

Liu Jizhen believes that there are three focus points on how to completely achieve energy transformation.

First, we will achieve revolutionary changes in the industrial structure, second, we will achieve disruptive breakthroughs in science and technology, and third, we will have revolutionary changes in the energy consumption culture and ecology of the whole society.

Regarding the third point, Liu Jizhen explained that our current energy consumption model is "source moves with the load", that is, the supply side ensures the demand side's demand; if it is gradually transformed into "supply and demand interaction", it will become the supply side and the demand side interaction to achieve synergistic efficiency of source and load; in the future, it will develop to "load moves with the source", and science and technology can determine the price mechanism by predicting power supply trends. "It can be foreseen that after the new power system is built, there will be a huge change in the way social energy consumption will be."