"Strive to peak carbon dioxide emissions by 2030 and strive to achieve carbon neutrality by 2060" is China's target commitment. To achieve the dual carbon goal, the central task is to replace the current carbon-based energy based on fossil energy with zero-carbon energy based on renewable electricity. It can be predicted that wind power and photoelectric power will be the main power sources in the future renewable power system, with the capacity accounting for more than 80% and the generating capacity accounting for about 60%.
However, in China to vigorously develop wind power and photoelectric, there are still difficulties. One is installation space. It is estimated that to add 6 gigawatts of wind power and photovoltaics, 100 million mu of land will be needed. Second, effective consumption. Different from thermal power, wind power and photovoltaics are not easy to control, and their changes are inconsistent with the demand for electricity. How to coordinate the relationship between power supply and electrical load, so as to effectively absorb their generating capacity, is the key to the development of wind power and photovoltaics at present.
In contrast, in China's vast rural areas, energy demand is strong, but there is a large space for carbon reduction and coal reduction, which urgently needs to be transformed into clean energy. Relevant data show that in 2019, China's rural loose coal consumption was about 140 million tons, accounting for more than 90% of the country's non-industrial loose coal, is one of the key coal and carbon reduction. Direct combustion of coal, diesel and straw as the main energy sources has also become an important cause of atmospheric and other environmental pollution. Combined with the above two factors, the author believes that the construction of a new rural energy system based on rooftop photovoltaic in China's rural areas may become an effective way to solve the difficulties of wind power photovoltaic development and help rural economic and social development.
What is a new rural energy system based on rooftop pv? In other words, in areas where natural conditions are suitable, the idle roof space of farmers will be fully utilized to develop a new DC microgrid with photovoltaic power generation as the core to provide comprehensive energy for rural production and life. At the same time, surplus electricity and processed or gasified biomass energy can be exported to cities, becoming a new economic source for grain producing areas.
By the calculation, if every roof installation of more than 20 kw photovoltaic, annual output can be more than 20000 KWH, can satisfy a family including the heating of the main room (50 square meters) of heating in winter and cooking, and all kinds of transportation charge of all daily use, can also be remaining close to 10000 degree of electric power for agricultural production and agricultural and sideline products processing, Surplus power can also be connected to the Internet at suitable times. In addition, through the construction of village-level DC micro-grid and public storage battery, it can also realize the mutual circulation and supplement of electricity between households. All kinds of electrical devices with power storage capacity and most loads in rural areas can be used in accordance with the demand response mode, so that most of the rooftop PHOTOVOLTAIC power can be effectively absorbed, and the rest can be connected to the Internet after the integration of village-level DC microgrid, and also transformed into adjustable and controllable high-quality power supply.
In this mode, the rural new energy system will realize the full electrification of production, living and transportation energy, and the rural atmospheric environment is expected to be completely changed. From the perspective of construction cost, the above configuration includes the village-level public part, which is equivalent to about 100,000 yuan of investment for each household. The annual income of public electricity and online power transmission can not only pay the operation and maintenance management fees, but also realize the installment repayment of all the initial investment and interest payments, so that all the electricity is free for households. At the same time, low-interest loans from banks can solve the problem of project investment sources.
So, how many rural roofs can be used in our country after all? According to the institute of tsinghua university and the ministry of land and resources satellite information cooperation investigation, all kinds of roof can be installed in rural areas about 2 billion kilowatts, photovoltaic power generation device can output close to 3 trillion KWH, throughout the year accounted for 2019 40% of the total electricity consumption in our country, more in China will reach the planned zero-carbon photovoltaic power system of 60% of the total. In the future, with the advancement of urbanization, China's rural population may decrease, but the scale of rural buildings and roofs will not decrease, and the scale of photovoltaic installed will also be stable at this level.
Rural photovoltaic roof, therefore, no matter on the power supply or volume control, can be zero-carbon power system play an important role for the future, except to meet rural production and living and traffic can use, but also for power grid, and power supply capacity of 800 million kilowatts at 1 trillion KWH of adjustable power supply, help to achieve the flexibility and stability of power system. Therefore, the development of a new energy system based on rural roof pv as soon as possible is not only conducive to rural revitalization, but also plays a crucial role in China's construction of a new power system with new energy as the main body and the realization of zero carbon power as soon as possible.
It should be emphasized that, under the guidance of the goal of "carbon peak carbon neutrality", the construction of a new rural energy system based on rooftop photovoltaic will also become a breakthrough in the construction of China's new power system. The low-carbon transformation of energy system will cause a series of revolutionary changes in China's existing power system. The grid will be transformed from the current unidirectional receiving to bidirectional active; The relationship between supply and demand of electric power has changed from "source with load" to "load with source". The stability of power grid changes from inertia of centralized power supply to distributed storage. These changes are not only related to basic research and technology research and development, but also involve the adjustment of power policy and pricing mechanism. To complete the construction of new electric power system under the premise of ensuring the safety of electricity consumption, social stability and sustainable economic development will be a revolution of electric power technology and electricity consumption culture to be further explored.
For the rural areas in the middle and east of China, the construction of electric power system is still relatively backward. The author believes that if the power system in these areas is replanned according to the model based on rooftop PV, the capital of the renovation can be used to invest in the renovation of this new way, which may reduce the financial pressure of the construction of rooftop PV system. At the same time, the transformation from centralized power system to distributed power system will not bring too much interference to rural economic and social activities. Due to rural electric power market accounts for only a small proportion of electricity market in China, that coincide with the new power system power policy and mechanism reform in rural areas first try, will not impact on the formation the whole electricity market, so in the region to explore pilot could provide reference for subsequent power system reform for reference.
Therefore, the construction of rural new energy system based on rooftop photovoltaic may be the breakthrough of the construction of new power system in China. This is not only an important part of building a new socialist countryside and implementing the rural revitalization strategy, but also expected to be the first step to achieve low-carbon development and complete the power system revolution in China.
Wuhan Xinshengneng is a professional manufacturer of electric power testing equipment. We pay close attention to the development and trends of power grid related industries. For more information, visit wuhan Xinshengneng's official website: www.whxsn.com
