Correctly understand the current tight balance between power supply and demand in some areas
2022-08-23
After several years of relatively loose power supply and demand environment, starting from the winter peak in 2019, China's power supply has again appeared a relatively tight situation. However, in 2021 and 2022, the power supply is tight in summer and winter peaks for two consecutive years, and even severe power supply tension has occurred in some areas. This is rare in the past ten years, and has attracted great attention from all sides. At present, it is the starting period to promote the realization of the "double carbon" goal. It is very important to correctly understand the current tight balance between power supply and demand, and scientifically and steadily promote energy transformation and the construction of new power systems.
Main reasons for tight balance between power supply and demand
Since the reform and opening up, China's energy and power supply has been in a tight state for most of the time. There were two periods of severe shortage, one in the 1980s and the other in the first 10 years of the 21st century. The shortage of power supply in these two periods is mainly manifested in two aspects: first, the power supply is seriously insufficient, unable to keep up with the rapid growth of power demand, and both power and electricity are in short supply; Second, the long-term "heavy power generation and light power supply do not work" has led to weak power grid structure, poor safety and stability of the transmission system, low equipment quality, weak distribution network structure, and power supply reliability and power quality do not meet the requirements. After decades of efforts, these two problems have been greatly improved. At present, China's power system has developed into an advanced power system with the world's most advanced, largest scale, strongest demand, high level of automation and digitization, high reliability and quality of power supply, and full of vitality and vigor. Under such a situation, the tight balance of power supply appears again, which is fundamentally different from the tense situation of power supply in history from the analysis of the causes and performance characteristics.
First, the tight balance between supply and demand in this round is mainly manifested in the tight power supply during peak hours. From the perspective of installed capacity and power load alone, the supply is sufficient, but in actual operation, it is difficult to achieve instantaneous power balance during peak hours. Among the 2.38 billion kilowatts of power generation installed in China, the installed capacity of thermal power and nuclear power that can dispatch and guarantee stable output does not exceed 1.36 billion kilowatts. The hydropower output is affected by factors such as climate, incoming water and reservoir regulation characteristics. New energy such as wind and wind cannot reliably and stably participate in power balance due to its characteristics. On the whole, at present, China's dispatchable power can only meet the peak load demand of about 1.3 billion kilowatts. Therefore, although the electricity is sufficient in the whole year, the electricity is insufficient in the peak period. It is necessary to take necessary measures to stagger the peak power consumption to ensure the real-time power balance of the whole system.
Second, new energy such as scenery has become an important challenge for real-time power balance. New energy such as wind power and wind power has the characteristics of randomness, volatility and intermittence. Its output often deviates from the trend of load curve fluctuation, that is, the output is low at the peak of load and high at the low of load. The system needs to reserve a large number of conventional thermal power units for peak regulation to hedge the imbalance caused by its fluctuations. With the increasing proportion of such power sources in the system, the capacity of peak shaving units that need to be standby for them is also increasing, and it is increasingly difficult to maintain the balance of power supply and demand. In case of extreme conditions, such as extremely low or even zero output of wind turbine and PV due to extreme weather, the supply and demand of the system may be unbalanced due to insufficient capacity of standby unit, and the load power consumption must be restricted to ensure the safety of the system.
Third, with the deepening of marketization, market factors such as the upstream of the industrial chain have become another important factor affecting the power balance. At present, in China's power system, coal-fired power supplies about 60% of the power generation with nearly 50% of the installed capacity, and undertakes more than 70% of the peak shaving tasks of the system. Coal-fired power is still the main power source in China, and is the "ballast stone" to ensure the power supply. It needs to consume a large amount of coal. Power coal security has a great impact on the balance of power supply and demand. In recent years, especially since the first half of last year, the price of coal in the upstream has increased significantly, and the cost of coal electricity has increased significantly. The increased cost can not be timely and effectively channeled, which brings great pressure to the normal operation of coal-fired power enterprises, and further affects the normal operation of coal-fired power units. In serious cases, coal-fired power generating units can not generate electricity, with installed capacity and no output, which will also have a great impact on the balance of power supply and demand.
Fourth, the timely response of the downstream demand side of the industrial chain can make greater contributions to the balance of power supply and demand. The survey shows that the power load of most provinces exceeds 95% of the maximum load, and the total duration of the whole year is generally about dozens of hours. Except for some provinces, the power load exceeds 90% of the maximum load, and the total duration of the whole year is only more than 300 hours. With the change of power consumption structure, the peak valley difference of power load becomes larger and larger. Therefore, it is beneficial to further stimulate users to actively participate in demand side management and increase demand side response in improving power supply and demand balance, ensuring power supply security, and improving the utilization efficiency of energy resources.
Fifthly, the distribution network structure in some areas is weak and cannot meet the power demand during the peak period. The performance is more prominent in old urban areas, remote areas and places where the development is too fast and exceeds the planning expectation.
China's primary energy resources are not well endowed, especially the high-quality energy resources are not abundant, the per capita energy resources reserves are low, and the total energy resources are not high. However, China's total energy demand is large in scale and rapid in growth. In addition, the regional imbalance problem is prominent, the total balance and regional balance fluctuate, and tension and relaxation alternate. At the same time, energy transformation and new power system construction, as a system project, cannot be smooth sailing, and there may be repeated fluctuations on the way. Overall, in the long future, the tight balance of power supply will be a feature of China's energy supply.
Take the tight balance between power supply and demand as an opportunity to promote China's energy and power transformation
The task of energy and power transformation in China is particularly arduous, and it will go through a time process. In this process, it will be the primary and fundamental task to do everything possible to ensure energy and power supply. The tight balance between power supply and demand will make us pay more attention to finding new alternative primary energy, paying more attention to the efficiency of energy power development and utilization, paying more attention to the optimization and adjustment of energy power and national economic structure, and paying more attention to the balanced and orderly development of energy power and national economy.
First, cherish and make good use of fossil energy resources. At present, wind power, solar energy, hydropower and other renewable energy have become an important part of energy supply, but they cannot replace fossil energy for a long time. Fossil energy resources are currently known energy resources with high energy density, mature development and utilization technology, relatively economic, and have played an important role in production and life. They can not be separated for a period of time. In the absence of reliable alternative energy, it is a scientific and rational choice to make full use of existing resources, achieve clean and efficient utilization as much as possible, and resolutely prevent "carbon rush" and "Sports" carbon reduction.
Second, vigorously develop other energy resources. In order to ensure a diversified energy structure and stable and sufficient supply, it is also necessary to actively explore other types of energy. For example, we should actively expand the scale and utilization of nuclear energy on the basis of ensuring safety. We should actively develop marine energy. In addition to making full use of offshore wind energy and solar energy, we should also strengthen the development and utilization of energy resources in the ocean and deep ocean. The development of marine energy is still in its infancy, and it may become one of the directions of overtaking in the international energy field.
Third, improve the efficiency of energy development and utilization. China's energy utilization efficiency is lower than the global average level, and the energy consumption per unit output value is more than twice that of the European Union and the United States. Given the scarcity of energy resources, greater efforts should be made to save energy and reduce consumption, actively develop advanced technologies for energy development and utilization, and maximize the value of energy.
Fourth, further strengthen and improve energy management. The development of energy resources, the efficient utilization of energy, and the environmental protection should be taken into account. The development and utilization technologies of new energy, new technologies for energy conservation and consumption reduction, recycling technologies such as carbon dioxide, and energy storage technologies indispensable to the new power system should be well coordinated and promoted. At the same time, energy transformation requires a large amount of capital investment. The external internalization process of energy use and the development and utilization process of new energy will raise the price of energy terminal consumption. Therefore, the whole society should strengthen the awareness of energy cost saving. In the process of formulating energy policies, government departments should also give full and comprehensive consideration to the issue of channeling reasonable costs.
Source: International Power Grid
Main reasons for tight balance between power supply and demand
Since the reform and opening up, China's energy and power supply has been in a tight state for most of the time. There were two periods of severe shortage, one in the 1980s and the other in the first 10 years of the 21st century. The shortage of power supply in these two periods is mainly manifested in two aspects: first, the power supply is seriously insufficient, unable to keep up with the rapid growth of power demand, and both power and electricity are in short supply; Second, the long-term "heavy power generation and light power supply do not work" has led to weak power grid structure, poor safety and stability of the transmission system, low equipment quality, weak distribution network structure, and power supply reliability and power quality do not meet the requirements. After decades of efforts, these two problems have been greatly improved. At present, China's power system has developed into an advanced power system with the world's most advanced, largest scale, strongest demand, high level of automation and digitization, high reliability and quality of power supply, and full of vitality and vigor. Under such a situation, the tight balance of power supply appears again, which is fundamentally different from the tense situation of power supply in history from the analysis of the causes and performance characteristics.
First, the tight balance between supply and demand in this round is mainly manifested in the tight power supply during peak hours. From the perspective of installed capacity and power load alone, the supply is sufficient, but in actual operation, it is difficult to achieve instantaneous power balance during peak hours. Among the 2.38 billion kilowatts of power generation installed in China, the installed capacity of thermal power and nuclear power that can dispatch and guarantee stable output does not exceed 1.36 billion kilowatts. The hydropower output is affected by factors such as climate, incoming water and reservoir regulation characteristics. New energy such as wind and wind cannot reliably and stably participate in power balance due to its characteristics. On the whole, at present, China's dispatchable power can only meet the peak load demand of about 1.3 billion kilowatts. Therefore, although the electricity is sufficient in the whole year, the electricity is insufficient in the peak period. It is necessary to take necessary measures to stagger the peak power consumption to ensure the real-time power balance of the whole system.
Second, new energy such as scenery has become an important challenge for real-time power balance. New energy such as wind power and wind power has the characteristics of randomness, volatility and intermittence. Its output often deviates from the trend of load curve fluctuation, that is, the output is low at the peak of load and high at the low of load. The system needs to reserve a large number of conventional thermal power units for peak regulation to hedge the imbalance caused by its fluctuations. With the increasing proportion of such power sources in the system, the capacity of peak shaving units that need to be standby for them is also increasing, and it is increasingly difficult to maintain the balance of power supply and demand. In case of extreme conditions, such as extremely low or even zero output of wind turbine and PV due to extreme weather, the supply and demand of the system may be unbalanced due to insufficient capacity of standby unit, and the load power consumption must be restricted to ensure the safety of the system.
Third, with the deepening of marketization, market factors such as the upstream of the industrial chain have become another important factor affecting the power balance. At present, in China's power system, coal-fired power supplies about 60% of the power generation with nearly 50% of the installed capacity, and undertakes more than 70% of the peak shaving tasks of the system. Coal-fired power is still the main power source in China, and is the "ballast stone" to ensure the power supply. It needs to consume a large amount of coal. Power coal security has a great impact on the balance of power supply and demand. In recent years, especially since the first half of last year, the price of coal in the upstream has increased significantly, and the cost of coal electricity has increased significantly. The increased cost can not be timely and effectively channeled, which brings great pressure to the normal operation of coal-fired power enterprises, and further affects the normal operation of coal-fired power units. In serious cases, coal-fired power generating units can not generate electricity, with installed capacity and no output, which will also have a great impact on the balance of power supply and demand.
Fourth, the timely response of the downstream demand side of the industrial chain can make greater contributions to the balance of power supply and demand. The survey shows that the power load of most provinces exceeds 95% of the maximum load, and the total duration of the whole year is generally about dozens of hours. Except for some provinces, the power load exceeds 90% of the maximum load, and the total duration of the whole year is only more than 300 hours. With the change of power consumption structure, the peak valley difference of power load becomes larger and larger. Therefore, it is beneficial to further stimulate users to actively participate in demand side management and increase demand side response in improving power supply and demand balance, ensuring power supply security, and improving the utilization efficiency of energy resources.
Fifthly, the distribution network structure in some areas is weak and cannot meet the power demand during the peak period. The performance is more prominent in old urban areas, remote areas and places where the development is too fast and exceeds the planning expectation.
China's primary energy resources are not well endowed, especially the high-quality energy resources are not abundant, the per capita energy resources reserves are low, and the total energy resources are not high. However, China's total energy demand is large in scale and rapid in growth. In addition, the regional imbalance problem is prominent, the total balance and regional balance fluctuate, and tension and relaxation alternate. At the same time, energy transformation and new power system construction, as a system project, cannot be smooth sailing, and there may be repeated fluctuations on the way. Overall, in the long future, the tight balance of power supply will be a feature of China's energy supply.
Take the tight balance between power supply and demand as an opportunity to promote China's energy and power transformation
The task of energy and power transformation in China is particularly arduous, and it will go through a time process. In this process, it will be the primary and fundamental task to do everything possible to ensure energy and power supply. The tight balance between power supply and demand will make us pay more attention to finding new alternative primary energy, paying more attention to the efficiency of energy power development and utilization, paying more attention to the optimization and adjustment of energy power and national economic structure, and paying more attention to the balanced and orderly development of energy power and national economy.
First, cherish and make good use of fossil energy resources. At present, wind power, solar energy, hydropower and other renewable energy have become an important part of energy supply, but they cannot replace fossil energy for a long time. Fossil energy resources are currently known energy resources with high energy density, mature development and utilization technology, relatively economic, and have played an important role in production and life. They can not be separated for a period of time. In the absence of reliable alternative energy, it is a scientific and rational choice to make full use of existing resources, achieve clean and efficient utilization as much as possible, and resolutely prevent "carbon rush" and "Sports" carbon reduction.
Second, vigorously develop other energy resources. In order to ensure a diversified energy structure and stable and sufficient supply, it is also necessary to actively explore other types of energy. For example, we should actively expand the scale and utilization of nuclear energy on the basis of ensuring safety. We should actively develop marine energy. In addition to making full use of offshore wind energy and solar energy, we should also strengthen the development and utilization of energy resources in the ocean and deep ocean. The development of marine energy is still in its infancy, and it may become one of the directions of overtaking in the international energy field.
Third, improve the efficiency of energy development and utilization. China's energy utilization efficiency is lower than the global average level, and the energy consumption per unit output value is more than twice that of the European Union and the United States. Given the scarcity of energy resources, greater efforts should be made to save energy and reduce consumption, actively develop advanced technologies for energy development and utilization, and maximize the value of energy.
Fourth, further strengthen and improve energy management. The development of energy resources, the efficient utilization of energy, and the environmental protection should be taken into account. The development and utilization technologies of new energy, new technologies for energy conservation and consumption reduction, recycling technologies such as carbon dioxide, and energy storage technologies indispensable to the new power system should be well coordinated and promoted. At the same time, energy transformation requires a large amount of capital investment. The external internalization process of energy use and the development and utilization process of new energy will raise the price of energy terminal consumption. Therefore, the whole society should strengthen the awareness of energy cost saving. In the process of formulating energy policies, government departments should also give full and comprehensive consideration to the issue of channeling reasonable costs.
Source: International Power Grid