Lei Xianzhang, Academician of the German National Academy of Science and Engineering, Suggests Sichuan to Build a New Energy System to Help Achieve the “Carbon Peaking and Carbon Neutrality” Goals

As a major energy production province in China as well as an important resource export province of the West-East Electricity Transmission Project, Sichuan will definitely help achieve the “carbon peaking and carbon neutrality” goals by means of building a new energy system and promoting the green energy revolution. According to the Implementation Plan for Carbon Peak in Sichuan Province, Sichuan will take action in ten key categories. The proportion of non-fossil energy consumption in Sichuan will reach about 41.5% by 2025, and will reach about 43.5% by 2030, which will reshape the economic structure and energy structure in Sichuan, and profoundly change people’s ways of production and lifestyles.

What areas can Sichuan make efforts to help achieve the “carbon peaking and carbon neutrality” goals?

At the 2022 Tianfu Carbon Neutrality Forum held in Chengdu today (March 27), Lei Xianzhang, Academician of the German National Academy of Science and Engineering, Chief Scientist of Tianfu Yongxing Laboratory, and Director of Tianfu New Energy Institute, was interviewed by Hongxing News reporters and put forward the implementation of an electricity-hydrogen coupling coordinating mechanism supplemented by hydrogen-based energy, so as to ensure the safe supply of green energy. In addition, Lei proposed the concept of a construction path for power grid to achieve long-term electrical energy support, especially under extreme climate conditions, helping achieve the “carbon peaking and carbon neutrality” goals through the construction of cross-week, cross-month, and cross-season energy storage projects, as well as strengthening the construction of distributed active power supply.

Electricity-hydrogen coupling coordination

helps achieve the “carbon peaking and carbon neutrality” goals

“Achieving the “carbon peaking and carbon neutrality” goals is an significant transformation for China’s economy and society.” In Lei’s opinion, carbon neutrality is first and foremost a profound energy revolution. At present, the use of fossil energy accounts for more than 80% of the total carbon dioxide emissions. Hence, to reduce carbon dioxide emissions must start from the energy revolution, through developing new energy and zero-carbon energy to replace traditional fossil energy, forcing China’s economy to achieve a green transformation, so as to complete the transformation from industrial revolution to industrial civilization, and then to ecological civilization.

During the transformation process, we will inevitably face many challenges, including technological innovation and transformation, as well as the accommodation problem after the construction of large amounts of electricity generating projects from wind and solar energy.

Lei noted that the first challenge faced by energy substitution is the accommodation problem after the construction of plenty of electricity generating projects from wind and solar energy. In the future, China’s total installed capacity of electricity generating from wind and solar energy will be several times that of the present. Selections needs to be made whether to accommodate the electric energy totally relying on the power grid, or to accommodate it by other means on the spot.

The second challenge faced by energy substitution is the huge contradiction between the intermittent and random nature of electricity from wind and solar energy and the rigid power system supply. In other words, in order to ensure stability, the previous power grid mainly relied on thermal power, hydropower, and nuclear power by dynamically adjusting the power balance in accordance with the needs of the grid. While for the future power system based on new energy, both wind and solar energy are ‘excessively relying on good natural climate conditions’. Under such circumstances, how to ensure the new power system all-time power balance and dynamic stability of operation can become a major challenge.

In Lei’s view, faced with these major challenges, the goal of a high proportion of electricity from wind and solar energy can be ultimately achieved by 2060 through relying on technological innovation and building a full-time power accommodation and energy storage system, so that coal energy will gradually phase out with the power supply based on new energy being a stable power supply.

A critical path to developing clean energy is to develop clean electric energy, with a focus on the vigorous development of electricity generating from wind, solar, and hydropower energy. And Sichuan possesses abundant natural gas and hydropower resources. From the current point of view, clean power is unlikely to completely replace fossil energy, since clean power does not have the combustion properties of fossil energy and the ability to provide off-grid large-scale power. In order to completely replace fossil energy, hydrogen energy should perform as a supplement. That is, an electricity-hydrogen coupling coordinating mechanism supplemented by hydrogen-based energy should be implemented with clean power as the main energy source and coal and oil being replaced with hydrogen, to ensure the safe supply of green energy. “Accordingly, electricity-hydrogen coupling coordination will be an inevitable choice for China’s future energy development pattern.” And this is also one of the focal points of Tianfu Yongxing Laboratory.

How to build a new power system?

So how can we build a new power system?

First of all, it is necessary to ensure that the wind and solar energy can be timely and effectively accommodated during the development process.

“The current mode mainly relying on the power grid to accommodate electricity from wind, solar, and hydropower energy is far from enough. We must have various means to accommodate excess wind and solar energy on the spot.” Taking Europe as an instance, he noted that apart from power grid transmission, electric energy from wind, solar, and hydropower energy can also be accommodated on the spot for the production of hydrogen or hydrogen-based energy, which can be delivered to users through pipelines or other means. “Under this logic, we can have transmission channels for two clean energy, that is, to build a coordinated transmission network of electric energy and hydrogen energy coupling with power grid as the main body and hydrogen-based energy transmission as a supplement, so as to ensure green energy supply through electricity-hydrogen coupling coordination.”

“The new power system dominated by new energy faces urgent technical problems, whereas the biggest challenge comes from the intermittent and volatile power grid caused by the high proportion of electricity from wind and solar energy.” He told reporters that the law of power generation output and load in a day follows that surplus electricity needs to be accommodated when electricity load decreases at night, and insufficient electricity needs to be replenished during the daytime. Besides, it is a natural norm for an area to be without sunlight or wind for many days or even longer. Therefore, the new power system should not only balance the fluctuations in power and frequency of the power grid in a timely manner, but also balance the daytime output and load changes of the power grid. When there is a long-term power shortage in the power grid, it is also necessary to provide the power grid with energy storage technology with medium-term, long-term, and cross-season capacities.

From the current mature energy storage technologies and methods, though battery energy storage can solve the demand for hour-level and small amount of electricity, the problems of power fluctuation and frequency stability need to be figured out; Pumped storage or compressed air energy storage, and liquid air energy storage can provide hundreds of megawatts or even larger electricity with medium power, but the problem of daytime power imbalance needs to be solved, since the capacity of pumped storage and compressed air energy storage is limited when the power shortage of the grid continues across days and weeks.

“In brief, the power grid must have hour-level energy storage, cross-day energy storage, medium- and long-term, or cross-season energy storage capabilities.” Among them, special attention needs to be paid to medium- and long-term as well as cross-season energy storage, only by solving these problems, can the long-term safe and stable operation of the power grid be better guaranteed in the future,” he said.

Looking forward to the prospect of the “carbon peaking and carbon neutrality”: Reflections on the new tracks of Sichuan’s future industries

While constructing a new energy system and accelerating energy transformation, many core technologies for future industrial tracks are being nurtured. Lei Xianzhang said that make arrangements for key technologies of the future industries ahead of time will help lead the direction of industrial development.

Nowadays, the development of clean energy based on electricity from wind, solar, and hydropower energy has become a consensus of the whole society. In Sichuan, 80% of the power supply comes from hydropower, while Sichuan also enjoys a large amount of untapped high-quality wind and solar resources. “It can be said that Sichuan is a typical province where the energy end is dominated by clean energy.”

Sichuan’s electric energy from wind, solar, and hydropower energy provides favorable conditions for green hydrogen and hydrogen production, and for this reason, he suggested that Sichuan should focus on the research and development of hydrogen energy or hydrogen-based energy transportation technology as well as hydrogen application technology. In chemical industry where a large amount of hydrogen are applied, the construction of hydrogen transport experiment pipeline can be considered. And the same emphasis should be put on the development of hydrogen-oil transportation technology.

On the energy front, he proposed to vigorously enhance the strategic position of Sichuan’s hydropower resource development and planning. Hydropower is not only a kind of clean energy of Sichuan, but also a kind of strategic resource of China. When a high proportion of China’s renewable energy is connected to the grid in the future, hydropower resources, as one of the large-scale energy storage methods, will become the mainstay for the safe and stable operation in bulk power system. Furthermore, abundant hydropower can promote the development of hydrogen energy and hydrogen-based energy, and propel the development of midstream and downstream industries through electricity-hydrogen coupling.

In terms of energy stability, he suggested that electricity from wind, solar, and hydropower energy should be built into a stable power source. Looking ahead at what might happen and stabilizing energy supply is the solution to the imbalance between the rigid demand for power load and the shortage of electricity from wind, solar, and hydropower energy in extreme weather. To achieve this goal, he thought that Sichuan should rationally allocate the proportion of electricity from wind, solar, and hydropower energy in the local power grid, and build wind, solar, and hydropower resources into a clean power supply network that can complement and empower each other. At the same time, it is necessary to strengthen the construction of a national interconnected bulk power system, so as to realize the cross-regional complement and mutual benefit of power from different time zones, diverse climate endowments, and various natural attributes. In addition, it is recommended to realize long-term power support for the power grid, especially under extreme climate conditions, through the construction of cross-week, cross-month, and cross-season energy storage projects, as well as strengthening the construction of distributed active power supply.

From the perspective of four energy consumption terminals, such as industry, transportation, construction, and energy, Lei Xianzhang proposed that it is still far from perfect for Sichuan to realize the substitution of fossil energy. In Chengdu, for example, the total carbon dioxide emissions in 2019 were about 57.96 million tons, of which industrial emissions accounted for 30%, transportation emissions accounted for 28%, construction emissions accounted for 23%, and energy emissions accounted for 18%, with industry, transportation, and construction being the major emitters. Focusing on these areas, taking energy saving, carbon reduction, and circular economy as the starting point, vigorously implementing electrification and hydrogen energy (hydrogen-based energy) substitution, and upgrading industrial tracks are the strategic choices for Sichuan to achieve the “carbon peaking and carbon neutrality” goals.

Focusing on Chengdu, he mentioned that Chengdu is currently building a park city demonstration zone that practices the new development concept. In his opinion, the external performance of a park city reflects in “parks” and “zero-carbon”, but the core lies in the carbon neutrality industries in an advanced layout. “Chengdu’s carbon emissions are mainly focused on the use end. Therefore, there are two paths to reduce emissions in Chengdu, one is to reduce carbon dioxide emissions, and the other is to utilize carbon dioxide emissions in a green manner.”

In terms of industrial layout, he advised that Chengdu take heat pump technology as the main means of heat energy utilization as an important starting point for energy transformation, plan in advance for an industrial layout supported by large-scale heat pump technology and aided by energy storage materials, and strengthen the core technology research of the future industrial tracks to form new industrial tracks. Additionally, drawing on the German mode and experience, Chengdu should make efforts in getting through the ‘last kilometer’ of the commercialization of scientific and technological achievements, so as to transform and implement the achievements of colleges and universities.

“To sum up, green transformation is a process, not something that can be accomplished overnight. While vigorously building clean energy, we should rely on technological innovation and breakthroughs to achieve the industrialization and scalization of zero-carbon energy such as hydrogen energy and hydrogen-based energy. When the two problems of new energy accommodation and stable operation of new energy can be effectively addressed, then it can be a natural and gradual process for fossil energy such as coal and natural gas to phase out from China’s economy and society.” He believes that this goal must be realized, and it can, without doubt, be realized.

[ BY Peng Xiangping from Hongxing News  ]