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Each successive leap in transmission voltage has been a step forward in humanity’s journey toward electrification.

In 1891, the world’s first high-voltage transmission line was commissioned, with a voltage of only 13.8 kilovolts.

In 1935, the United States raised the transmission voltage from 220 kV to 275 kV, marking the first appearance of extra-high-voltage transmission lines in human society.

In 1959, the former Soviet Union completed the world’s first 500-kV transmission line, marking a major leap forward in humanity’s ability to harness electrical energy.

In 2009, the world’s first 1,000-kV Jindongnan–Nanyang–Jingmen UHV AC demonstration project was put into commercial operation—this time, it was China that led the way!

Unlike China’s world‑class technologies such as high-speed rail and 5G, in the field of ultra‑high‑voltage power transmission, China stands in a league of its own—reaching the pinnacle and surveying the world from above.

01.

Electricity, as an energy source, possesses certain unique characteristics: it is instantaneous and essentially non‑storable.

Storing energy in batteries is costly and offers very low energy density, making it economically unviable. Meanwhile, the barrier to generating electricity is relatively low—many residential neighborhoods and factories have their own emergency power generators, and even the engines of gasoline-powered vehicles can supply power to batteries during operation.

The non-storability of electric power means that generation and supply must be balanced—specifically, a dynamic equilibrium.

This brings us to the issue of power transmission.

In 2017, India’s electricity generation already ranked third worldwide, yet large parts of the country still experience frequent rolling blackouts—largely because its transmission lines lack sufficient capacity. Transmission power is given by P = U × I (voltage × current); to increase power, one must either raise the current or boost the voltage. However, excessive current leads to greater resistive heating in the lines, wasting energy and posing safety risks, which is why increasing the voltage is essential.

The higher the voltage, the greater the transmission capacity—allowing more power to be delivered with lower losses—and enabling long-distance transmission. In particular, long-distance transmission is crucial. Heat losses along the line are directly proportional to the wire length; if low-voltage transmission is used and the lines are excessively long, nearly all the electrical energy will be dissipated along the way.

Meanwhile, long-distance power transmission is essential for fundamentally addressing the imbalance between electricity supply and demand.

In the 1980s and 1990s, and even into the early 21st century, electricity was prioritized for industrial production, with residential use coming second. At that time, rural areas experienced scheduled power cuts, while urban areas implemented time-of-use pricing to curb peak‑hour consumption. Peak rates were more than three times higher than off‑peak rates. Why did electricity prices fluctuate so sharply within just a few hours? Because electric power is inherently “instantaneous”: when demand surges in the evening and supply falls short, raising prices serves to moderately reduce household consumption during those peak periods.

Factories, meanwhile, adopted staggered electricity‑use schedules to spread demand as evenly as possible. Even by the summer of 2003, 22 provinces nationwide were still implementing rolling blackouts, leaving residential electricity needs inadequately met and holding economic development hostage to the bottleneck of power shortages.

In China, 76% of coal, 80% of wind energy, and 90% of solar energy are concentrated in the western and northern regions, while 80% of hydropower is located in the southwest. Meanwhile, more than 70% of electricity consumption is concentrated in the eastern and central regions.

On the one hand, resource-rich provinces in the central and western regions have surplus electricity that goes unused and is wasted; on the other hand, economically robust eastern provinces face power shortages. Moreover, this imbalance between electricity supply and demand even exists across different regions within a single province.

Zhang Guobao, former deputy director of the National Development and Reform Commission and former director of the National Energy Administration, once recounted the following experience: Around the year 2000, while working at the Ertan Hydropower Station, he was in charge of power dispatch. At that time, Ertan was the largest hydropower station in China to have been completed and put into operation, yet its annual utilization hours stood at only 5,162—roughly equivalent to just seven months of full‑load operation. For the remaining five months of the year, the generating units remained idle.

Why?

Because the electricity that’s been sent out isn’t being used, we don’t know where to deliver it.

At the time, the electricity generated by the Ertan Hydropower Station could only be transmitted within Sichuan Province. Zhang Guobao approached Lu Tingchang, then Deputy Minister of the Ministry of Electric Power, hoping to export Ertan’s power. After doing the math, Lu Tingchang determined that with an installed capacity of 3 million kilowatts, a single 500-kilovolt AC transmission line could carry just over 900,000 kilowatts. To transmit Ertan’s output, at least one 500-kV line and three 220-kV lines would be required. Given China’s technological capabilities at the time, such a project would entail high costs and significant risks. Even amid a chronic imbalance between electricity supply and demand, there was no certainty that building high-voltage transmission lines would effectively resolve the problem.

Thus, at the time, power had to be generated and consumed locally. China’s energy distribution was accomplished through large-scale, long-distance coal transportation. In the early years of this century, more than 70 percent of newly added railway capacity was devoted to coal transport. Back then, there was a power plant every 30 kilometers along the Yangtze River—small and medium-sized facilities all fueled by coal. Why was the issue of illegal coal mines in Shanxi so severe over two decades ago? Because the low‑priced coal produced by these small operations was in extraordinarily high demand across the country.

Because coal is burned to generate electricity, in the economically developed Yangtze River Delta region, sulfur dioxide emissions reach 45 tons per square kilometer annually—20 times the national average.

At the time, a popular saying went: “Reinforce generation, neglect transmission and distribution, and ignore end‑user management.” Localities were highly motivated to build power plants and generate electricity, yet they paid insufficient attention to transmission and distribution infrastructure and even less to demand‑side management. As a result, despite the proliferation of power plants and rapid growth in total generation capacity, the fundamental imbalance in electricity consumption remained unresolved.

As urban development and industrialization in China continue to drive rising electricity demand, and as the tension between economic growth and environmental protection becomes increasingly pronounced, it has become imperative to launch projects for on-site thermal power generation.

02.

At the end of 2004, Liu Zhenya, who had been leading the State Grid Corporation for two months, joined the then‑top leader of the National Development and Reform Commission at the acceptance and summary meeting for the Three Gorges–Guangdong HVDC transmission project. Seated in a speeding minivan, as they discussed China’s chronic power shortage, Liu Zhenya expressed deep concern, noting that domestic electricity supply had “seriously held back economic development.”

Liu Zhenya is well‑placed to comment on this issue. Since joining the Linyi City Electric Power Bureau in Shandong Province in 1979, he spent twenty years working within the province’s power system. Recalling his experience in Shandong, he noted that at the time, the concept of an integrated power grid did not yet exist; wherever there was a power shortage, a power plant would be built—so long as coal could be transported to the site. In other words, “wherever new urban districts or industrial zones expanded, power plants were constructed accordingly.”

In 2000, Liu Zhenya joined the State Grid Corporation of China.

“Only by taking a broader perspective on China’s energy resources and electricity supply‑demand dynamics can we fully appreciate that the localized, balance‑oriented approach to power development is the root cause of the chronic strain on coal‑power transportation and the recurring, seasonally driven electricity shortages.”

To fundamentally address this challenge, it is essential to develop transmission lines with greater capacity, longer transmission distances, and higher voltage levels, thereby integrating the nation’s isolated regional grids into a single, large-scale grid. This will enhance the grid’s transmission capacity and, one day, enable nationwide electricity dispatch and allocation.

In 2004, after assuming the top leadership position at State Grid Corporation of China, Liu Zhenya embarked on a bold initiative to upgrade the national power grid: building “power highways”—ultra-high-voltage (UHV) transmission networks, comprising 1,000-kV AC and ±800-kV or higher DC transmission lines—and interconnecting them nationwide into a unified power supply network, thereby fundamentally resolving the longstanding challenge of China’s power sector being constrained by coal‑transport capacity.

Prior to this, China’s highest‑voltage transmission lines were 500 kV—specifically, the Gezhouba–Shanghai transmission line, which began construction in the 1980s and relied entirely on imported technology and equipment. Beyond that, at the time, the country’s transmission and transformation networks were predominantly configured at 330 kV and 220 kV.

▲The Geshu Line crosses the Huangpu River.

The 500-kV grid is heavily reliant on foreign technology, and now there’s a push to leap directly to 1,000 kV. Within the power‑grid community, there are voices of opposition, arguing that a more cautious, step‑by‑step approach is warranted—first consolidating the 500-kV system, then introducing 750 kV in select regions—since overly rapid expansion may not be sustainable.

Zhang Guobao and Liu Zhenya are firmly committed to a “one‑step” approach: they’ve already invested heavily in 750‑kV projects, yet within ten to fifteen years they’ll be pushing ahead with 1,000‑kV lines.

Compared with 500-kV extra-high-voltage AC transmission, 1,000-kV ultra-high-voltage AC transmission increases the transmission distance by a factor of 2 to 3, boosts the transmission capacity by a factor of 4 to 5, reduces transmission losses to one-third, requires only one-third of the right-of-way width, and entails construction costs of just 70% of the conventional level.

Compared with ±500 kV ultra-high-voltage DC transmission, ±800 kV and ±1100 kV extra-high-voltage DC transmission systems increase transmission distances by 2–3 times and 5–6 times, respectively; boost transmission capacities by 2–3 times and 4–5 times, respectively; reduce transmission losses to less than one-half and one-quarter, respectively; require corridor widths per unit capacity of only 65% and 55%, respectively; and entail capital costs of just 65% and 40%, respectively.

It is highly necessary to achieve a breakthrough in one go over the course of ten or twenty years; ultra-high-voltage transmission is the infrastructure underpinning the “West-to-East Power Transmission” project. Moreover, we must exercise ample imagination when considering the pace of China’s development—this point was repeatedly emphasized by both of them.

In January 2005, State Grid Corporation of China launched a feasibility study on ultra-high-voltage (UHV) transmission and submitted its findings to the National Development and Reform Commission (NDRC) later that year. The NDRC approved the project promptly; on February 16, it issued a directive to “initiate preliminary research on China’s 1-million-volt AC and ±800-kV DC UHV transmission technologies.” On March 21, a meeting chaired by leaders of the State Council was held, during which Liu Zhenya presented a report. At this meeting, the development of an UHV grid was explicitly endorsed, and UHV technology was incorporated into the national plan for major equipment.

However, the challenges have only just begun.

When you set out to tackle a new task, navigating by trial and error can actually be quite rewarding—because far too often, you don’t even get the chance to feel for those stones.

Building ultra-high-voltage transmission lines falls into this category.

At that time, no country in the world had ultra-high-voltage transmission lines.

In the 1960s, the United States began exploring 1,000-kV ultra-high-voltage transmission. Although the technology was largely mastered and plans for project implementation were already under way, the oil crisis of the 1970s and the wave of deindustrialization dealt a severe blow, leading to the collapse of U.S. efforts in this area. Crucially, the U.S. power grid is locally owned and highly fragmented; large-scale transmission using ultra‑high‑voltage technology simply did not align with the realities of the American electricity system.

Japan, meanwhile, completed two ultra-high-voltage transmission lines in the 1980s. However, as its economy continued to decline and nuclear safety incidents occurred from time to time, the Japanese government gradually scaled back its nuclear power capacity, causing these ultra-high-voltage lines to be downgraded to high-voltage lines.

The former Soviet Union was much the same: in 1985, it completed a 900-kilometer ultra-high-voltage transmission line, which operated intermittently for five years. Following the dissolution of the Soviet Union in 1991, electricity demand along that line steadily declined, and the UHV system eventually ceased to exist.

These three developed countries have all abandoned the project—so why is China determined to pursue ultra-high-voltage transmission? Can this project really succeed, and is it truly practical? These were the questions that lingered in many people’s minds at the time.

03.

In May 2005, a report titled “Issues and Recommendations Regarding the Development of Ultra-High-Voltage Power Grids” was submitted to the State Council. At that time, less than two months had elapsed since the State Council had approved the initiation of ultra-high-voltage transmission projects.

This report raised concerns regarding the safety and necessity of the ultra-high-voltage project, prompting the State Council, in line with a principle of utmost prudence, to decide to convene another high-level deliberation meeting.

From June 21 to 23, 2005, the National Development and Reform Commission convened a seminar on ultra-high-voltage transmission technology in Beidaihe. The presentation materials displayed at the venue were half a meter thick, and more than 200 participants attended, including both electrical engineering experts and power‑equipment specialists.

The arguments primarily focus on four aspects: the comparison between electricity transmission and coal transportation, the safety of ultra-high-voltage transmission, maintenance and operational costs, and electromagnetic environmental impacts.

These four issues can, in fact, be grouped into two broad categories: the coal‑power comparison serves as a prerequisite for determining whether ultra‑high‑voltage projects are necessary, while the remaining three pertain to measures ensuring their successful implementation.

According to the analytical calculations, electricity from the large coal-fired power bases in northern and western China, transmitted via ultra-high-voltage lines to the load centers in the eastern and central regions, has a grid‑connected price that is 0.06 to 0.13 yuan per kilowatt-hour lower than the local benchmark coal‑fire power tariff. In other words, electricity delivered through UHV transmission is roughly 10 cents cheaper per kilowatt-hour.

In 2004, Shanghai’s annual electricity consumption was approximately 90 billion kilowatt-hours. If ultra-high-voltage transmission were deployed, the city could reduce its annual electricity costs by 9 billion yuan, with the investment recouped in two to three years. Of course, the unemployment resulting from the closure of small coal-fired power plants around Shanghai represents a separate issue.

However, at least from the perspective of whether to transport coal by rail or by power grid, a consensus was quickly reached after discussion: transmitting electricity via the grid is indeed cheaper than shipping coal by rail.

Meanwhile, on issues of safety, maintenance costs, and electromagnetic interference, a protracted debate has ensued.

The conclusion of this Beidaihe meeting was that the UHV project could proceed, though several key issues still required further study. To gain a comprehensive understanding of UHV development, Liu Zhenya personally led a delegation on an inspection tour; while in Japan, he even got off the train midway and walked uphill beneath the transmission lines to gauge just how loud the noise was.

On October 31, 2005, the National Development and Reform Commission convened its second expert review meeting, during which some opponents continued to voice concerns about safety and called for a temporary suspension of the development of ultra-high-voltage transmission technology.

Under the circumstances at the time, both self‑doubt about domestic technological capabilities and blind admiration for European and American countries became obstacles to the UHV project. Progress even fell into a vicious cycle: “experts submitted petitions—State Grid Corporation reported—government conducted reviews—experts submitted further petitions—State Grid reported again—government reviewed once more,” repeating endlessly, leaving everyone thoroughly exhausted.

Looking back on that period, Zhang Guobao remarked with deep feeling: “Don’t even mention Liu Zhenya—people like us were left physically and mentally exhausted.” In fact, debate itself is not the problem; the real issue lies in engaging in endless discussion without ever reaching a decision.

Ultimately, it was the State Council that made the final decision.

On New Year’s Day 2006, the “National Medium- and Long-Term Plan for Science and Technology Development (2006–2020)” was released, explicitly including ultra-high-voltage transmission technology.

With this, Liu Zhenya and his State Grid are finally ready to roll up their sleeves and get down to business.

04.

Wang Shaowu, currently the director of the UHV Department at State Grid Corporation of China, was then working on the UHV technology R&D team. When State Grid launched its ultra-high-voltage projects, he had graduated less than five years earlier and was still considered something of a “rookie.” However, since no one within the company at the time had experience with UHV projects, he was given the opportunity to take a front‑line role.

He recalled that, fresh out of school at the time, during a visit to the Gezhouba–Shanghai HVDC transmission project, he found virtually no domestically produced equipment—indeed, even the duty‑room chairs in the converter station and the toilets in the substation had been imported as complete, pre‑assembled units.

Under such circumstances, achieving world-class standards is understandably extremely challenging.

The 1,000-kV ultra-high-voltage transmission system is not merely a scaled-up version of the 500-kV extra-high-voltage system; it still has numerous critical technological gaps that need to be addressed, and further research and development are required for many supporting components.

Of course, this is not a task for State Grid to undertake alone; dozens of research institutes and universities, more than 200 equipment manufacturers, and over 500 construction firms are collaborating to tackle key challenges and carry out 309 major research projects on critical technologies.

To accelerate project progress while ensuring safety, State Grid places great emphasis on testing and verification. It has successively established the UHV DC Test Base, the UHV AC Test Base, the UHV Engineering Mechanics Test Base, the High-Altitude Test Base, the State Grid Simulation Center, and the UHV DC Transmission Project Integrated Design and R&D (Testing) Center—comprising a total of four test bases and two centers.

Among these, the National Grid Simulation Center is particularly important; countries rely on simulation-based calculations as the basis for assessing grid security. In a simulated power system, analysts evaluate whether transmission lines at various voltage levels and operating generators could potentially jeopardize the stability of the main grid.

Accordingly, the China Electric Power Research Institute has established a world‑leading power system simulation platform. It has conducted comprehensive simulations of an ultra‑large UHV AC/DC hybrid power system—comprising a grid ranging from 220 kV to 1,000 kV, 2,258 generators, 35,932 transmission lines, and 11,547 nodes—modeling over 100,000 fault scenarios and operating conditions, thereby thoroughly validating the safety and reliability of the UHV grid.

We have also achieved breakthroughs in critical core components.

The bottleneck in ultra-high-voltage transmission lies in the transformer equipment, whose core component is the converter valve. The most challenging part of the converter valve is the thyristor. At the time, two options were available: a 5-inch version, which could be manufactured domestically and posed relatively lower technical challenges, and a 6-inch version, which had never been produced or used anywhere in the world.

The 5-inch model has a current-carrying capacity of 3,000 amperes, while the 6-inch model can handle up to 6,000 amperes.

The prevailing view within State Grid is to prioritize stability above all else, but Liu Zhenya has consistently maintained that if action is to be taken, it should be done in one decisive step.

At 6 inches, the entire world is still a blank slate, requiring joint R&D efforts with ABB worldwide. Liu Zhenya spoke with great confidence: “Only China has this opportunity; once it leaves China, there will be nowhere to apply this technology.”

Joint research and development is, in essence, our chance to catch up: foreign companies earn their profits, while we acquire the necessary expertise; afterward, China’s vast domestic market can be firmly in our own hands.

On this point, Zhang Guobao sees it more clearly:

“We are not simply purchasing equipment from others; we aim to manufacture it domestically, particularly key components such as ultra‑high‑voltage transformers, switchgear, and insulation. We must adhere to one principle: the R&D of major equipment must be closely integrated with major engineering projects. Without such integration, R&D efforts that remain isolated will yield products no one needs, resulting in substantial costs and ultimately failing to deliver any tangible benefits.”

In December 2007, Xuji Electric and ABB signed an agreement for the joint research and development of thyristors. In May 2009, Xuji Electric submitted its deliverables to State Grid, with all tests successfully completed—five months ahead of the schedule stipulated in the contract.

Moreover, benefiting from the growth of its ultra-high-voltage business, Xuji Electric saw its revenue surge rapidly, jumping from RMB 3 billion in 2009 to RMB 8.7 billion in 2013. With robust financial and technological support, the company has intensified its R&D efforts; today, its smart substation and distribution systems have surpassed the ultra-high-voltage segment to become a major source of revenue.

 

▲Xuji Electric’s net profit

From national needs and technological breakthroughs to downstream enterprises, a virtuous closed-loop relationship for ultra-high-voltage transmission has thus been established.

05.

On January 6, 2008, the 1,000-kV Jindongnan–Nanyang–Jingmen UHV AC transmission line was put into commercial operation. It is the world’s first UHV transmission line to achieve commercial operation.

On July 8, 2010, the Xiangjiaba–Shanghai ±800 kV ultra-high-voltage direct-current transmission demonstration project was put into operation, marking the State Grid Corporation of China’s full entry into the era of an ultra-high-voltage AC/DC hybrid grid.

As of the end of 2020, China had completed and put into operation 35 UHV projects—14 AC and 16 DC—and was constructing an additional 2 AC and 3 DC lines, bringing the total length of UHV transmission lines in operation and under construction to 48,000 kilometers.

High operating voltage, strong transmission capacity, and advanced technological standards—these records have been repeatedly broken by State Grid Corporation of China.

We have established a globally comprehensive technical standards system for ultra-high-voltage transmission, fully owned with independent intellectual property rights, and have further developed a complete set of technical standards and specifications covering the entire lifecycle of UHV AC and DC projects—from design and manufacturing to construction, commissioning, operation, and maintenance.

China’s standards are international standards.

On September 26, 2019, the world’s longest transmission line—the Jun Dong (Xinjiang)–Southern Anhui ±1100 kV ultra-high-voltage direct current transmission project—was officially put into operation.

3,324 kilometers—from Xinjiang to Anhui—spanning six provinces and crossing half of China. With a transmission capacity of 12 million kilowatts, it can meet the electricity needs of 50 million households. This means that the power transmitted along this single line alone could supply the residential electricity consumption of both Anhui and Henan provinces. Annually, it reduces coal consumption by 38 million tons—equivalent to eliminating the need for 10,000 freight trains.

Based on current transmission capacity, this would reduce coal transportation by approximately 190 million tons annually and cut emissions by about 320 million tons of carbon dioxide, 1 million tons of sulfur dioxide, and 940,000 tons of nitrogen oxides.

From the State Council’s approval in 2006, to the official commercial operation of the first UHV transmission line in 2009, and now with 35 completed UHV projects, the pace of UHV transmission development has been no slower than that of high-speed rail. Why did the United States, the Soviet Union, and Japan all stumble on UHV technology, while only China succeeded?

Two reasons.

First, it’s a matter of our institutional framework: by design, our system excels at mobilizing resources to tackle large-scale projects. More importantly, a behemoth like State Grid possesses the decisive resolve to make final, binding decisions.

Recalling the time when he was determined to develop ultra-high-voltage transmission, Liu Zhenya said with deep emotion, “At that time, seeing that both Japan and Russia had failed to achieve success with UHV, I felt tremendous pressure. But for the sake of national development, no matter how great the risks, we had to make UHV a success.”

Even when there were initial objections arguing that ultra-high-voltage transmission was overly ambitious, once the decision was made, State Grid was able to withstand the pressure and press ahead with unwavering resolve. After a single transmission line was completed, the evidence on the ground would inevitably silence its critics.

But things don’t work that way overseas. California’s high-speed rail project was first approved in 2008, yet construction didn’t begin until 2015, with several prolonged interruptions along the way. After President Biden took office, the project was revived, but it’s still not expected to open until at least 2027. Why is building a high-speed line just over 300 kilometers so difficult? It’s not just a matter of land acquisition and funding; persistent opposition keeps muddying the waters—for example, some state legislators have demanded that all equipment and technology used in the project be sourced entirely from the United States.

Building the first high-speed railway required 100% domestic production of its technology; even for the United States, a global superpower, achieving this within a short timeframe would be impossible, and the project’s schedule would inevitably be delayed.

Then there’s Tesla’s Gigafactory project in Germany. At first, Musk had high hopes for the German plant, envisioning it as a super‑engine for Tesla, much like the Shanghai factory. But these days, Musk no longer entertains that fantasy.

 

▲A German factory in July this year

At the Berlin plant, even the preliminary land‑clearing took more than six months. Local residents and environmental groups blocked the start of construction on various grounds, including—but not limited to—protecting trees, safeguarding underground water sources, conserving bats in the forest, and refraining from disturbing snakes that were hibernating.

Electric vehicles have already burst onto the scene, poised to upend the internal‑combustion‑engine car industry, yet they still leisurely tout “protecting the environment” and preaching the need for harmony between humanity and nature.

Without the courage to make decisive calls and the composure to see them through, even the most important undertakings will ultimately fizzle out amid endless wrangling and internal infighting.

The second reason is market-related.

The attempts at ultra-high-voltage transmission in the United States, the Soviet Union, and Japan all failed—not because of technological limitations, but due to insufficient demand. Without a massive electricity consumption base, ultra‑high‑voltage transmission would be pointless. For such a system to function, the nation must operate as a fully powered industrial machine, with a dense population engaged in economic activity, capable of absorbing ample amounts of electrical power.

A large population base combined with being a major manufacturing country—only under these conditions does a UHV transmission project justify its implementation.

Ultra-high-voltage transmission, in and of itself, is neither a technology nor an engineering endeavor; rather, it is a large-scale project that demands comprehensive consideration. The hand that underpins it is less the Chinese power grid than China as a whole—the world’s largest industrial nation.

Written at the end

China’s tech companies—State Grid is undoubtedly one of them.

In the ranking of companies by the number of invention patents filed over the past five years, State Grid Corporation of China tops the list with 23,308 patents.

 

But this is not the end; ahead of State Grid, there remain numerous challenges that must be overcome step by step.

For example, in the core area of transformer technology, we still lag behind the world’s leading companies, ABB and Siemens.

For example, when it comes to choosing between DC and AC transmission, we still tend to favor one over the other. To elaborate: ultra‑high‑voltage DC is like a train marked with a “Z” — it runs straight through without stopping along the way, whereas ultra‑high‑voltage AC is more like a highway: it may not be quite as fast, but it offers exits and places to stop.

Therefore, the advantage of DC transmission lies in its strong transmission capacity, enabling high‑power, long‑distance point‑to‑point power delivery; however, it cannot form a grid and lacks the capability to integrate, transmit, and accommodate power within a network.

For a long time, we have placed great emphasis on the efficiency and cost of power transmission, which has led to the persistent issue of “strong DC, weak AC.” By developing AC transmission lines, we can enhance the synchronous interconnection among power grids and ensure the safety and stability of the national grid as a whole.

For example, if the North China grid experiences a power shortage while the Central China grid has surplus capacity, cross‑grid transmission support could be provided. However, to date, there is only a single ultra‑high‑voltage AC transmission line connecting the two grids, which falls short of effectively balancing supply and demand.

Moreover, energy utilization rates remain relatively low in the western provinces that are major energy producers.

According to 2019 data from the National Energy Administration, Xinjiang, Gansu, and Inner Mongolia—three provinces (autonomous regions)—accounted for a combined 13.6 billion kWh of curtailed wind power, representing 81% of the nation’s total curtailed wind energy. In the Northwest region, curtailed solar power accounted for 87% of the national total, while Tibet, Xinjiang, and Gansu recorded solar curtailment rates of 24.1%, 7.4%, and 4.0%, respectively.

Here, vast amounts of clean energy are still being wasted—gifts from nature that we, in turn, return to it.

 

Sichuan Province’s power grid has a load of 35 million kilowatts, yet the province’s installed hydropower capacity totals 90 million kilowatts—more than 70 percent of which comes from hydroelectric sources. For instance, the Baihetan Hydropower Station alone boasts an installed capacity of 16 million kilowatts. Because the generated electricity cannot be fully transmitted, many power plants are forced to sell their output to small cryptocurrency‑mining operations at prices as low as a few cents per kilowatt-hour.

The problems that Zhang Guobao encountered back then at the Ertan Hydropower Station have, in fact, still not been fully resolved today.

Looking ahead, our goal is to build a truly comprehensive and interconnected power grid—a global energy internet—whose reach extends not only across China but throughout the world.

UN Secretary-General António Guterres has stated that China’s ultra-high-voltage technology is essential for the development of renewable energy, and that the Global Energy Interconnection is central to achieving sustainable human development and a key enabler of inclusive global growth.

What is the Global Energy Internet?

The power grid in the Middle East suddenly collapsed, so our hydropower units in the southwest were urgently brought online to generate electricity and feed it into the grid. Coordinated across several major AC transmission networks, power was delivered to Dubai within minutes.

Liu Zhenya said: “Without broadband technology, could the world truly become a global village? And without ultra-high-voltage transmission technology, the Global Energy Internet would be nothing more than a pipe dream—yet today, it is a concrete, actionable reality.”

The surging waters of the Jinsha River roar as they drive the turbines, and once fed into the grid, they illuminate the streetlights that light up Afghanistan’s nights.

The blazing sun on the Qinghai-Tibet Plateau shines upon vast arrays of photovoltaic panels, and its energy travels two thousand kilometers to ensure that villages in Southeast Asia no longer suffer from intermittent power supply.

The fierce winds on the neighboring beach set the windmill’s massive blades spinning, bringing a touch of winter’s warmth to every household on the Siberian plains.

This is the true community with a shared future for mankind.

As we bring China’s power grid to the world, our journey has only just begun.