1.6 trillion, which is the total amount of ultra-high voltage construction in China from 2006 to 2025 (20 billion was invested from 2006 to 2010, 500 billion was invested from 2011 to 2015, 700 billion was invested from 2016 to 2020, and a budget of 380 billion was 2021 to 2025)
from South Network and the "three interchange and four direct" 7 lines built by State Grid , and then by 2025, it will complete the "24 interchange and 14 direct" and involve more than 30,000 kilometers of lines.
Along with the controversy, UHV construction has been going on for 16 years. The main controversy point is 2 points. If it is not built abroad, is it necessary for China? The second one is whether it is worth it or not.
China has built the global technical standard for ultra-high voltage
First of all, why not do it abroad? UHV refers to the voltage levels of DC with ±800 kV and above and 1000 kV and above AC . The Soviet Union was one of the first countries in the world to carry out research on ultra-high voltage transmission technology, and was also the only country in the world with experience in operating ultra-high voltage transmission projects. In the end, other countries have no relevant applications for various reasons. Even the Soviet Union eventually dropped to an ultra-high pressure level.
This has led to the fact that there is no mature technology and equipment in the world, and there is no complete technical standard system for reference.
China began to study ultra-high voltage technology much later than them. It can be said to be a counterattack model and built the ultra-high voltage technical standard with its own strength. my country's ultra-high voltage technical standard is an international standard. At present, China's largest technology source country in the world is China. As of May 26, 2022, the number of ultra-high voltage equipment patent applications in China reached 318,387, accounting for 41.42% of the total global ultra-high voltage equipment patent applications, which is more than the United States and Japan.
As for another problem, that is, why China needs to spend huge amounts of money to build ultra-high voltage power grids, which is caused by the imbalance of national resources.
UHV can solve the problem of unbalanced power resources in China
my country's primary energy has a pattern of "more north and less south" and "more west and less east" in terms of regional distribution. 76% of coal resources are in the north and northwest, 80% of hydropower resources are in the southwest, and land wind energy is mainly concentrated in the northwest, northeast and northern North China, but more than 70% of the energy demand is in the central and eastern regions, so this is extremely inconsistent with my country's regional economic development level and energy consumption level.
Simply put, it means that the economic development of the eastern coastal cities has large demand for electricity, but the power resources are not sufficient. However, the industrial structure of the northwest and southwest regions is relatively single, and the electricity surplus has caused energy waste. For example, Yunnan has abundant water resources and surplus electricity every year. Every year, I am worried about how to deal with this electricity. How did
before? Wherever there is power shortage, coal is transported to wherever there is a shortage of electricity. Some provinces are still wasted electricity, and the capacity bottleneck restricts the supply of electricity and coal. Regional and seasonal power shortages occur repeatedly. The other is that there is a high pollution. The more economically developed and densely populated areas, the more coal-fired power plants are built and the more dense they are. In the past, a power plant from Nanjing, Jiangsu to Zhenjiang, an average of 10 kilometers was 10 kilometers, and the air pollution exceeded 5 times the national average.
The emergence of ultra-high voltage solves the problem of power distribution, with low voltage level transmission power loss large. Therefore, increasing the voltage level is for long-distance transmission, which can reduce the power loss of long-distance transmission.
Generally speaking, the economic transmission distance of the 500 kV ultra-high voltage transmission line is usually 600 to 800 kilometers, while the 1000 kV ultra-high voltage can reach 1000 to 1500 kilometers or even longer. In addition, the 1000 kV AC ultra-high voltage transmission line has a capacity of 5 times that of the 500 kV ultra-high voltage transmission line. Therefore, some people use ultra-high voltage transmission as a provincial highway, at most it is a national highway, while ultra-high voltage transmission can be said to be a "power expressway".
In addition to the low efficiency of power transmission, the ultra-high transmission line heating power poses great safety hazards. Therefore, ordinary power grids cannot bear the heavy responsibility of power distribution.
This is to understand the second reason why foreign countries are not built is that many countries have a small land area and the demand for large-capacity power transmission is relatively weak. Some countries with large land areas, such as the United States, have very rich resources, and the Central Plains also make it less urgent for UHV long-distance and large-capacity power transmission. Of course, there are also some countries with huge land area and unreasonable allocation of electricity resources, but they do not have such technology.
UHV technology can build a smart grid
. Is it worth it? UHV power grid has such an advantage. It can connect the Chinese power grid and build a smart grid so that different power plants built in different places (such as between thermal power plants and hydropower plants) can support and supplement each other, and achieve unified management and distribution of electricity. This can also promote the intensive development of coal and hydropower resources in the west, and can also protect the environment more effectively.
To put it simply, building a smart grid through ultra-high voltage, wherever there is a shortage of electricity, it will reduce power generation or save electricity.
You are like the drought and power shortage problem in Chongqing this year. Chongqing has coal, but low-hot coal has high sulfur content, which is used to generate electricity with high pollution and high cost. Chongqing has no oil, and solar, wind and biomass energy are not dominant. At present, Chongqing's energy dependence on foreign energy has exceeded 30%. Once ultra-high voltage is built, electricity can be transported from other places to alleviate the power shortage problem in Chongqing.
In 2016, after Hubei Province suffered the most severe floods since 1998, the autumn and winter showed a significant dry period, and hydropower generation dropped significantly. When the electrodes are tight, the 5 million kilowatts of electricity input from the UHV power grid from the north is basically guaranteed to Hubei's electricity demand.
In fact, the development of ultra-high voltage technology is of great significance to ensuring China's energy security, and will also drive the upgrading and transformation of other industries, such as the ultra-high voltage industry chain, photovoltaic industry, new energy vehicle industry, and the domestic production rate of ultra-high voltage equipment exceeds 90%, and the construction of global ultra-high voltage technology standards is guaranteed, that is, the autonomy of China's energy has also enhanced China's voice in the global power market.
UHV technology is of great significance to solving global energy problems
Then at this time we can summarize the statement, is it necessary to build ultra-high voltage? It is necessary, and China also wants to solve global energy problems through ultra-high voltage technology, such as building a large intercontinental energy transmission channel.
For example, Sahara Desert has rich and developable solar energy resources, but it is sparsely populated and cannot absorb so much electricity. Now, with ultra-high voltage, it is possible to transport the energy from the Sahara Desert to available areas. According to research data from Chinese scientists, each line of intercontinental transmission can transmit electricity to about 66 billion kilowatt-hours per year. Sahara 's solar energy can meet the electricity needs of the entire Europe.
In the later stage, with the improvement of new energy efficiency and breakthroughs in new materials and energy storage technologies, new energy from Central Asia, Middle East , North Africa and other regions can be directly transported to Europe on a large scale. In this way, multiple lines are moving forward simultaneously, and there is no need to worry about being destroyed.
In addition to Europe, China can also cooperate with interested countries to build a transnational smart grid, conduct unified management and allocation of electricity, and help other countries solve the energy crisis .
It can be said that ultra-high voltage is a trump card in China. When the world encounters an energy crisis, the value and significance of this trump card are highlighted.
