Exclusively Reveals the Past & Present of China’s Ultra-High Voltage (First Half)

Under the circumstances of “no standards, no experience, and no equipment” in the world, China’s UHV has successfully transformed from “starting from scratch” to “a major country with important equipment”, from “Created in China” to “Leading by China”, from “Equipment in China” to “Equipment World”. It can be said that the construction of UHV power grid is the most difficult, most innovative and challenging major achievement in the history of my country’s power development. It is also an important milestone in the development of the power industry in China and the world.

In the context of carbon peaking and carbon neutrality, the UHV power grid has become China’s energy transportation “main artery” for “transmitting electricity from the west to the east, power from the north to the south, water and fire complementing each other, and wind and solar complementing each other”, cracking the development of energy and electricity. The deep-seated contradictions have achieved a fundamental transformation of energy from local balance to large-scale allocation, and effectively promoted the clean and low-carbon transformation.

As of the end of 2020, China has completed a total of 35 UHV projects, including “14 UHV lines, 16 UHV lines” and “2 UHV lines, 3 UHV lines” under construction. The total length of UHV lines in operation and under construction is 48,000 kilometers.

“Now that UHV work has been successful, people say that I am the ‘Father of UHV’. I think it should be ‘UHV’s loss’, the winner or loser. Over the years, I have suffered many scars because of my insistence on doing UHV. , who can you tell me this?” Liu Zhenya, former chairman of the State Grid Corporation of China and chairman of the Global Energy Internet Development and Cooperation Organization, said with emotion.

In the future, the construction of a global energy Internet with UHV as the backbone network will promote the development of global clean energy bases, interconnection of power grids in various continents and countries, promote the integrated development of the “three networks” of energy network, transportation network, and information network, and provide solutions for resource constraints and environmental problems. To overcome global challenges such as pollution, climate change, poverty and disease, we will open up new paths and make new contributions to the sustainable development of human society.

At the end of 2004, Liu Zhenya, who had been at the helm of State Grid Corporation of China for two months, and the main leaders of the National Development and Reform Commission at the time attended the acceptance summary meeting of the Three Gorges-Guangdong DC Transmission Project. On the speeding minibus, Liu Zhenya was deeply worried about the current situation of power shortage in China. Domestic power supply has “seriously hindered economic development.”

Large-scale, long-distance coal transportation has always been the main way of allocating energy resources in China. More than 70% of the new railway transportation capacity is used for coal transportation. At the beginning of this century, my country had a power plant every 30 kilometers along the Yangtze River. The annual sulfur dioxide emissions in the Yangtze River Delta region reached 45 tons per square kilometer, which is 20 times the national average. This is inseparable from the reverse distribution of China’s resource endowment and load. 76% of China’s coal, 80% of wind energy, and 90% of solar energy are distributed in the western and northern parts, 80% of hydropower is distributed in the southwest, and more than 70% of electricity consumption is concentrated in the east and central regions. Energy-rich areas are far away from the east and central regions. The demand center is about 1,000 to 4,000 kilometers away.

Regarding the questions about solutions from the main leaders of the National Development and Reform Commission, Liu Zhenya, who calls himself the “electrician class leader”, came up with a “clever idea”: building an “electric highway” – an ultra-high voltage power grid, to completely reverse the long-term problem of China’s power development being restricted by coal transportation capacity.

UHV refers to 1000 kV AC and ±800 kV DC transmission technology. It has many advantages such as long transmission distance, large capacity, high efficiency, low loss, low unit cost, and space saving, and can effectively solve the problem of energy supply. Safety, existing power grid is unsafe, ecological environment is unsafe and other issues.

How to fundamentally solve the contradictions between limited fossil energy resources and rapid growth in demand, tight coal and electricity transportation and insufficient energy resource allocation capabilities, and difficulties in the development and consumption of clean energy?

Liu Zhenya described the formation of the UHV idea this way: “Before 2000, I worked in Shandong. At that time, power plants were built wherever there was a power shortage. They did not pay attention to the power grid, and rarely considered whether there was coal or whether the transportation capacity was sufficient. In 2000 Later, when I came to Beijing and looked at my country’s energy resources and electricity supply and demand from a higher level, I realized that the locally balanced electricity development model was the root cause of my country’s long-term tight coal and electricity transportation and periodic and seasonal power shortages. To fundamentally solve this problem, we must develop a power grid with larger transmission capacity, longer transmission distance, and higher voltage level, improve the power grid’s ‘transport capacity’, and one day be able to distribute electricity nationwide. “

In fact, Liu Zhenya, who had just taken the helm of the State Grid Corporation of China, proposed the development of ultra-high voltage when he chaired the first party meeting. After the meeting, the State Grid Corporation of China submitted a document to the country on the development of UHV. The curtain of China’s UHV development has officially begun.

If we go back even further, Liu Zhenya’s confidence stems from the fact that China’s need for higher voltage levels was already covered in his graduate thesis.

The “smart idea” of UHV transmission, which has been brewing in Liu Zhenya’s mind for many years, impressed everyone. At the acceptance summary meeting of the Three Gorges-Guangdong DC Transmission Project that day, they said that UHV transmission is “a good idea and method to solve energy problems.” , should be “researched and considered in power planning.”

After the Spring Festival in 2005, the State Grid Corporation of China launched a feasibility study. On February 16, the National Development and Reform Commission issued a document (National Development and Reform Office Energy [2005] No. 282) proposing to “start preliminary research work on my country’s million-volt AC and plus-minus 800,000-volt DC UHV transmission technologies.” On March 21, leaders of the State Council presided over the meeting, and Liu Zhenya made a report. The minutes of this meeting (Guoyue [2005] No. 21) clearly agreed to develop UHV power grids and incorporate UHV into the national major equipment plan.

After many years of planning, UHV construction has pressed the “acceleration button”. But not long after the development of UHV was approved by the leadership of the State Council, a voice of opposition also emerged.

In May 2005, a report entitled “Problems and Suggestions on the Development of UHV Power Grids” was submitted to the State Council. It is proposed whether it is necessary and safe to build a 1,000-kilovolt power grid on top of the existing 500-kilovolt power grid.

Three days later, the State Council asked the National Development and Reform Commission to organize expert discussions. A protracted UHV “debate” began.

From June 21 to 23, 2005, the National Development and Reform Commission organized a UHV transmission technology seminar in Beidaihe. The demonstration materials placed at the venue were half a meter thick. “More than 200 people attended, including both electrician experts and power equipment experts.”

The questions raised by experts mainly focus on four aspects: comparison of coal and power transmission, UHV economy, safety and electromagnetic environmental impact.

In fact, compared with 500 kV ultra-high voltage AC transmission, the 1000 kV UHV AC transmission distance is increased by 2-3 times, the transmission capacity is increased by 4-5 times, the transmission loss is only 1/3, and the corridor width is only 1 /3, the unit cost is only 70%.

Compared with ±500 kV UHV DC transmission, the transmission distance of ±800 kV and ±1100 kV UHV DC has increased by 2-3 times and 5-6 times respectively, and the transmission capacity has increased by 2-3 times and 4- 5 times, the transmission loss is less than 1/2, 1/4, the unit capacity corridor width is only 65%, 55%, and the unit cost is only 65%, 40%.

Compared with coal transportation, the power from the large coal power bases in the northern part of the west is transported to the load centers in the east and central part through UHV, and the grid electricity price is 0.06-0.13 yuan/kWh lower than the local coal power benchmark grid electricity price.

In addition, the electromagnetic environment indicators of UHV transmission projects all meet national standards, and the noise is significantly lower than that of 500 kV transmission projects.

From the commissioning of my country’s first UHV project in 2009 to now, my country has built 30 UHV AC and DC projects, fully verifying the safety of UHV. With the strong support of the UHV power grid, my country’s power grid is currently the only ultra-large power grid in the world that has not experienced large-scale power outages.

At the meeting, most people were in favor of implementing UHV. Even if some people raised issues that needed improvement or attention, they generally agreed with it. The State Grid Corporation of China called on “the conditions for carrying out the construction of test demonstration projects are already in place, and it is recommended that the test demonstration projects be approved as soon as possible.”

In late September 2005, the feasibility report of the Southeast Shanxi-Nanyang-Jingmen 1000 kV AC UHV test demonstration project successfully passed national approval.

After the Beidaihe Conference, the development of UHV did not go smoothly, and some institutions and personnel once again raised different opinions.

On October 31, 2005, the National Development and Reform Commission held its second demonstration meeting and specially invited those who opposed UHV to attend.

The meeting invited old leaders such as former Minister of Electric Power Shi Dazhen and former Vice Minister of Electric Power Lu Yanchang. The participating experts wrote written opinions and signed their names.

After the two meetings, objections still focused on issues such as the safety, economy, and reliability of UHV, especially the application of AC UHV technology and the resulting AC synchronous power grid and large power grid security. There are different opinions. After the Spring Festival in 2006, some people once again proposed to carefully consider the development of UHV technology.

UHV once became a sensitive topic, and began to fall into the “strange circle” of “experts petition – State Grid Corporation of China report – government demonstration – experts petition again – State Grid Corporation of China report again – government demonstration again”.

Later, Zhang Guobao, the former deputy director of the National Development and Reform Commission and the former director of the National Energy Administration, recalled in the book “A Blue Thread”: “Due to too many disputes, the construction of UHV was delayed.” “Don’t talk about Liu Zhenya, people like us People feel physically and mentally exhausted. In fact, it is not terrible to argue, but there is a problem with just arguing without making a decision.”

On November 27, 2006, the State Grid Corporation of China held an international seminar on UHV transmission technology. At the meeting, Koval, then Secretary-General of the International Conference on Large Power Grids, believed that there was no technical feasibility problem in developing UHV. At that time, opinions were relatively unanimous on whether to develop UHV technology.

However, in the face of the fact that the first UHV project has been operating safely for more than five years, and many subsequent UHV projects have been completed and operated safely, some people still continue to question it.

To this end, in March 2014, the National Committee of the Chinese People’s Political Consultative Conference organized a special survey. On May 15, the National Committee of the Chinese People’s Political Consultative Conference held a bi-weekly consultation symposium to study major issues related to the development of UHV. At the meeting, the State Grid Corporation of China made a comprehensive and systematic report on major issues such as why it needs to develop UHV technology, why it needs to build a “Three China” synchronous power grid, and why UHV power grids need to coordinate the development of AC and DC. This meeting greatly promoted the development of UHV, but the original opponents still persisted in their opposition.

In any case, the National Committee of the Chinese People’s Political Consultative Conference, the Beidaihe Conference, the National Development and Reform Commission meeting, and the UHV International Conference are all unavoidable ideological debates in the history of China’s UHV development.

The dilemma of “ideological liberation”. In the process of UHV development, the biggest problem faced is first of all ideological issues.

China’s power industry has been accustomed to following the footsteps of developed countries in Europe and the United States for decades. Some people have fixed mindsets and believe that foreigners can’t do it, and Chinese people can’t do it either.

But it seems that no matter how high the UHV develops, it will never wake up those who pretend to be asleep. Therefore, at different stages of UHV development, different voices will always appear. In the early days, some people suggested that our country does not need UHV, and the existing voltage levels can meet the requirements; later, it was also pointed out that the core technology of UHV cannot be solved by the Chinese, and the key equipment cannot be manufactured; during the project construction stage, it was pointed out that the electromagnetic environment problem cannot be solved; After it was put into operation, it was pointed out that the equipment was unreliable and the power grid was unsafe and uneconomical. After many projects had been running safely and stably for many years, it was also pointed out that UHV AC was not needed and only UHV DC was needed. Arguments escalated. As Shi Dazhen, the former Minister of Electric Power, said: “If we hold on to old views, no one will develop. I just hope some people can wake up earlier.”

Two days before New Year’s Day in 2006, UHV transmission technology was officially included in the “National Medium and Long-term Science and Technology Development Plan (2006-2020)”. However, some people still pointed out that the planning outline did not mention the voltage level and did not clearly say it was ultra-high voltage.

In this regard, Zhang Guobao recalled: “Some people said that the “Outline” did not say what the voltage level was, and did not point out ultra-high voltage. Later I looked through it and it was clearly written in it. DC is ±800 kilovolts and AC is 1,000 kilovolts. “I think the development of ultra-high voltage is still the consensus of most scientific and technological workers.”

In order to actively respond, the State Grid Corporation of China has reported to the State Council many times and written multiple reporting materials, explaining that there is no inevitable connection between the voltage level and scale of the power grid and safety. The key to ensuring the safety of the power grid is the advancement, applicability and operation management level of the power grid’s structure and technical means.

In order to fully understand the development of UHV, the State Grid Corporation of China has organized experts to conduct field inspections in Japan, Russia and other countries. In 2005, during his inspection in Japan, Liu Zhenya even stopped and hiked up the mountain to listen to the noise of UHV lines. At that time, Japan built UHV transmission lines, but they were always operated at a reduced voltage of 500 kV. Three single-phase transformers for testing at the UHV test station, manufactured by Hitachi, Toshiba, and Mitsubishi, were always powered for trial operation. During an inspection in Russia, I saw that the UHV switches developed during the former Soviet Union had as many as 12 fractures (China’s UHV switches generally have 2 fractures), which were bulky and rough. This was also limited by the technology and materials at the time.

Through inspection, foreign UHV development is either still in the research stage, or there is no commercial operation due to technical or economic reasons.

“At that time, I saw that Japan and Russia’s UHV projects were both unsuccessful. I was under a lot of pressure. But for the sake of national development, no matter how big the risk was, we had to make UHV projects a success.” Many years later, Liu Zhenya used the two words “fear”. There are only one word to describe this journey.

Although the process of ideological emancipation is arduous, without emancipation, it is impossible to promote the innovative development of UHV. The best way to quell controversy is obviously to prove it with facts. As Shi Dazhen, the former Minister of Electric Power, said in 2015, the domestic debate on UHV has not ended yet, but the actual results achieved in the past decade have proven that even if there are different opinions, UHV is a path that must be taken.

Not finished yet! Please read second half part. Thanks!