Soon after the Fukushima Dai-Ichi nuclear meltdown in March 2011, Germany announced it would decommission all its nuclear plants. Switzerland and Italy rejected proposals to build more reactors. Japan shut down its reactors and has yet to restart them. China, on the other hand, plowed ahead with existing projects, even though it suspended new approvals so it could perform more safety checks.
Last November, the government lifted the moratorium and approved four projects. The number of reactors being built is now 29—the most of any country, and 40 percent of the world’s total. “China is now one of the most important countries, if not the most important country, in the global nuclear industry,” says Antony Froggatt, a senior research fellow at Chatham House, a British think tank.
China is likely to become the first country in which new reactor designs are built and tested at full size. Chief among them is the AP1000—AP stands for “advanced passive”—designed by Westinghouse Electric, the U.S. company now majority-owned by Japan’s Toshiba. The AP1000 is, in theory, safer than previous models because it has an 8 million-pound water tank perched on its roof; in the event of a power outage or generator failure, it provides an emergency cooling system powered by gravity for up to three days—a window of time estimated to be long enough to avert a meltdown. “The operator doesn’t have to do anything,” says Sandy Rupprecht, who runs business and project development for Westinghouse. Froggatt notes that with no orders in Europe and construction plans behind schedule in the U.S., Westinghouse needs a working reactor in China to show possible customers that its model is viable and safe.
China is also building a pebble-bed reactor, a dream of nuclear scientists since German engineers tried to build one in the 1960s. This kind of reactor should run at extremely high temperatures—900C (1,650F) or more; other reactors operate at around 400C—and use helium as a coolant and graphite instead of water as a moderator, which slows down neutrons in a reactor’s core to increase the chances of inducing nuclear fission.
In theory, a pebble-bed model operates much more efficiently than other designs. “The problem has been that although graphite is slippery when it’s cool, at high temperatures and when it’s heavily radiated it gets more sticky,” causing the graphite pebbles to get lodged in one place, explains Steve Thomas, professor of energy studies at London’s University of Greenwich. “When the pebbles stick, they overheat and start to disintegrate, leaving a dust of fuel products and radioactive graphite.”
Construction on the reactor began in December. The design came from Beijing’s Tsinghua University. If successful, it would be the first full-size prototype of this technology. If unsuccessful, it would be a costly, dangerous mess to clean up. Germany’s pebble-bed prototype, which was never operational, cost €5.5 billion ($7.3 billion) to decontaminate.
The Chinese are also testing the radioactive chemical thorium, said to be safer than uranium, as a nuclear fuel. That program was launched in 2011 in Shanghai by former President Jiang Zemin’s son, Jiang Mianheng.
China’s engineers have already adapted the Westinghouse technology into a larger design, called the CAP1400, which increases the power the reactor can produce from 1,000 megawatts to 1,400 megawatts. “They took the American design and basically stretched it,” says Arnie Gundersen, chief engineer for consultant Fairewinds Energy Education. Construction on China’s first CAP1400 is expected to begin this year. At a Feb. 1 press conference in Beijing, Gu Jun, president of State Nuclear Power, said, “Exploration of the global market for the CAP1400 will start in 2013.”
One hurdle for China’s export drive: New technology needs the blessing of the U.S. Nuclear Regulatory Commission, which is “still regarded as the global accrediting body,” says Bo Kong, assistant research professor at Johns Hopkins School of Advanced International Studies. “China has to convince the rest of the world it has the ability to build safely and securely.”
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