Under the vision of carbon peak and carbon neutralization, China's energy structure transformation has entered a key stage. As a major coal power province in China, Inner Mongolia is accelerating the progress of flexible transformation of coal power, issuing incentive policies and mechanisms to realize the coupling development of traditional coal power and new energy power generation, which has stimulated the enthusiasm of flexible transformation of coal power plants. Several demonstration pilot projects are advancing in order to help improve the regulation capacity of power supply side and effectively solve the problem of new energy consumption.
Coal power flexibility transformation is imperative
Building a new power system with new energy as the main body is the basis for achieving carbon peak and carbon neutralization. Inner Mongolia is rich in scenery resources. During the '14th five year plan', it is proposed to implement the new energy multiplication plan. By 2025, the installed capacity of new energy in the whole region will account for more than 50% and become the main energy of power in the whole region.
In this context, the balanced and safe operation of power grid will face no small challenge. The wind power output of Inner Mongolia is mainly concentrated in spring and winter, and the photovoltaic output is mainly concentrated in summer and autumn. With the significant increase in the proportion of the total installed capacity of 'scenery', the real-time balance of the power grid is becoming more and more difficult, and it is urgent to greatly improve the regulation capacity of the power system.
However, China's power flexibility is still insufficient. According to the research on flexible operation policy of coal-fired power units issued by China Power Council, the installed capacity of power generation in China is mainly coal-fired power, and the installed capacity of flexible regulation power sources such as pumped storage and gas-fired power generation accounts for less than 6%. The proportion of flexible regulation power sources in the 'Three North' areas rich in new energy is lower, less than 3%, and the regulation capacity is inherently insufficient.
'There are nearly 300 coal-fired power plants in Inner Mongolia. During the 13th Five Year Plan period, only the fourth five year plan home appliance plants completed the flexible transformation.' Liu Siyuan, deputy director of the power department of the Energy Bureau of Inner Mongolia Autonomous Region, said that at present, the proportion of flexible regulated power supply in the whole region is less than 6%. Limited by resource endowment and other conditions, pumped storage power stations in Inner Mongolia have few resources and poor economic bearing capacity for gas-fired power generation, In addition, at this stage, the scale and quantity of energy storage are insufficient, and various mechanisms such as dispatching operation and market transaction are still improving. The flexibility transformation of coal and electricity has become an effective measure to solve the high proportion of new energy consumption.
Market oriented measures to solve the problem of insufficient incentive
In order to speed up the flexibility transformation of coal-fired power, Inner Mongolia recently issued an action plan for the flexibility transformation of coal-fired power (2021-2023), which proposes to strive to complete the flexibility transformation of coal-fired generating units in the region by 2023, and increase the system regulation capacity by 4-5 million KW.
Specifically, Inner Mongolia requires to improve the regulation capacity of new coal-fired power units. The minimum technical output of new heating units during heating period shall not exceed 35%, and the minimum technical output of new coal-fired power units under pure condensation condition shall not exceed 25%; The flexibility transformation of the active coal motor unit shall be implemented. After the transformation, the minimum technical output in the heating period shall not exceed 40%, and the minimum technical output under pure condensation condition shall not exceed 30%.
The goal has been clear, how to effectively land it? 'In the past, the flexibility transformation of coal-fired power has been pushed forward slowly. The key is that compared with the hard requirements of ultra-low emission transformation and elimination of backward production capacity, the flexibility transformation is not mandatory.' Liu Siyuan said that taking the power plant with two 300000 kW coal-fired units as an example, the cost of flexibility transformation is at least about 30 million yuan; The deep peak shaving operation of coal power will increase the unit coal consumption, affect the service life of the unit, and reduce the power generation of the power plant, affecting the economic benefits. 'If there is no reasonable economic return, it is difficult for the power plant to bear the loss of peak shaving.'
Therefore, the establishment of the corresponding incentive mechanism is particularly critical. Inner Mongolia will improve supporting measures, increase support for advanced units with flexibility indicators, increase peak shaving space for power generation enterprises after thermal power flexibility transformation, and build market-oriented grid connected new energy at a proportion of no less than 50%. At the same time, improve the construction of auxiliary service market mechanism, increase the peak shaving compensation of peak shaving auxiliary service market in Mengxi, establish a reasonable auxiliary service cost sharing compensation mechanism, and improve the willingness of market subjects to participate in system regulation.
Liu Siyuan said that the characteristic highlight of promoting the flexibility transformation of coal power in Inner Mongolia is to encourage coal power plants to build new energy power generation projects, leverage the flexibility transformation of coal power with new energy, realize the coupling development of coal power and new energy power generation, change the opposition between coal power and new energy zero sum game, and greatly stimulate the main enthusiasm of power plants, The implementation of renewable power generation substitution in traditional coal-fired power plants will eventually promote the transformation of traditional coal-fired power plants into new green power plants with both coal and green power.
From the perspective of power plants, there is great pressure on energy transformation, and they are actively striving for new energy projects; At the same time, coal prices are rising this year, and the power generation efficiency of coal-fired power plants is declining. We are more and more aware of the urgency of turning to new energy. 'The policy of building market-oriented grid connected new energy for the flexibility transformation of coal and electricity put forward by Inner Mongolia is just in line with the current market nodes and industry needs, and effectively promotes the flexibility transformation of coal and electricity.' Liu Siyuan said.
The pilot of flexible transformation moves forward sonorously
Inner Mongolia encourages flexible transformation of various types of coal-fired power units such as public, external and self provided. At present, all League cities are actively applying for coal power flexibility transformation projects, and the demonstration pilot projects of some power plants have been started.
Linhe thermal power plant of Huaneng north company, as one of the first demonstration pilot units for flexible transformation of thermal power units of the national energy administration, invested more than 40 million yuan to carry out flexible transformation of two 300000 kW units, and completed the transformation of 9 key projects such as thermal power decoupling. The peak shaving capacity of the unit is greatly improved, the minimum electrical load of the unit can be reduced to 25% in a short time under pure condensation condition, and the electrical load can be reduced to 30% tha load on the premise of meeting the heating extraction flow of 300t / h (or equivalent heating capacity) in winter, so as to realize thermoelectric decoupling.
According to industry analysis and calculation, after the implementation of thermal power flexibility transformation project for two units of Linhe thermal power plant, the annual power generation of units with low load peak shaving is 448 million kwh, saving 143000 tons of standard coal and 491000 tons of carbon dioxide emission reduction, effectively helping the local government to realize 'dual control of energy consumption', which is of great significance for energy conservation and emission reduction.
Wu Jialiang, deputy general manager of Linhe thermal power plant, said that in order to further solve the problem of low flue gas temperature during flexible peak shaving and low load of the unit, in the next step, the power plant plans to invest more than 30 million yuan to increase the bypass flue. After the implementation of the project, the deep peak shaving capacity of the unit can be reduced to 25% of the rated load to ensure that the nitrogen oxide emission does not exceed the standard during the safe operation of the unit under low load for a long time.
Jungar banner is a banner county rich in coal and power resources in Inner Mongolia. The local government has also strengthened the transformation of coal-fired power units. It is planned that from 2021 to 2023, five Mengxi Power Grid public power plants subordinate to Guohua, Shenhua and other groups will participate in the thermal power flexibility transformation. After the transformation, the new energy development and consumption scale can be increased by about 1.32 million KW.
The reporter learned that the Energy Bureau of Inner Mongolia Autonomous Region organizes a centralized declaration every year, and the power competent departments of each league and city formulate the annual thermal power flexibility transformation scale of the region according to the maturity of thermal power flexibility transformation and safe operation constraints. Liu Siyuan said: 'judging from the current response, all localities and power plants are very proactive, have a strong willingness to carry out flexible transformation, and are expected to complete the task of the three-year action plan ahead of schedule.'