Japanese television brought the catastrophe into millions of living rooms throughout the country, where viewers watched in horror as an explosion struck a nuclear reactor in Fukushima.
The explosion on Saturday blew off the roof of the reactor building, sending a cloud of thick white smoke into the air. When the smoke had dissipated, only three of what had been four white reactor buildings were still visible.
Nothing but a ghostly shell remained of the fourth building.
The outside walls of the reactor 1 building had burst. The steel shell that contains the red-hot fuel rods apparently withstood the explosion, but it was unclear if a major disaster could still be averted. In addition, four other reactors in Fukushima's two power plant complexes were not fully under control.
Then, on Monday, a second explosion hit the Fukushima Daiichi plant, this time involving the facility's reactor 3. The blast injured 11 workers and sent a huge column of smoke into the air. It was unclear if radiation leaked during that explosion, which was apparently caused by a build up of hydrogen, with the plant's operator saying that radiation levels at the reactor were still below legal limits. The US reacted to Monday's explosion by moving one of its aircraft carriers, which was 100 miles (160 kilometers) offshore, away from the area, following the detection of low-level radiation in its vicinity.
Shortly afterwards, the government announced that the cooling system for the plant's reactor 2 had also failed. The explosions at reactors 1 and 3 had been preceded by similar breakdowns. The Jiji news agency reported on Monday that water levels at reactor 2 had fallen far enough to partially expose fuel rods.
The television images on the weekend left no doubt: The highly advanced island nation had apparently experienced the worst nuclear catastrophe to date in the 21st century, triggered by the worst earthquake in Japanese history.
A short time after Saturday's blast, Chief Cabinet Secretary Yukio Edano appeared on the main TV channel and spoke about the accident -- in the manner of a teacher telling students during a class trip what they are going to do next. Then a grey-haired expert on nuclear power plants joined Edano and appealed to the population to remain "reisei," to stay calm and cool.
Reisei, reisei: It was as if the government was more concerned about cooling down the heads of Japanese citizens than the partially melted nuclear fuel rods.
Advised to Stay Indoors
When the reactor exploded in Chernobyl a quarter century ago, the Soviet Union immediately brought in thousands of workers to cover the overheated reactor core with sand and lead. Eventually almost a million people would be involved in securing the reactor. But the Soviet Union was not simultaneously faced with the consequences of an earthquake and a tsunami.
The efforts of the Japanese police to evacuate a large area surrounding the reactor seemed more frantic than levelheaded. Thousands of people fled to the south in their cars.
At first, it was difficult to assess how dangerous the radiation in the immediate vicinity of the reactor was. Experts at the site reported that radiation levels of one sievert per hour had been measured near the reactor. This is a high level, but nothing compared with the 200 sievert per hour to which some emergency workers in Chernobyl were exposed.
Various radioactive materials are released in a meltdown, including plutonium and uranium, and the highly dangerous substances iodine 131 and cesium 137, which also contaminated the environment surrounding Chernobyl. It was confirmed that at least small amounts of cesium were also released at Fukushima. On Saturday German Foreign Minister Guido Westerwelle, the leader of the liberal Free Democratic Party (FDP), advised Germans to leave the areas affected by the tsunami and the nuclear accident.
A Japanese government spokesman advised citizens to stay indoors, switch off their air-conditioning systems and, if necessary, hold a moist towel in front of their mouths. These are all indications of how helpless the stricken industrialized nation's reaction was in the hours following the accident.
The fact that Japan, which was once considered a miracle economy, was on the verge of a nuclear disaster could be far more devastating to the nuclear industry than the Soviet reactor catastrophe in Chernobyl could ever have been a quarter century ago.
Admittedly, Japan is in an earthquake zone, which puts it at greater risk than countries like Germany and France. But Japan also happens to be a leading industrialized nation, a country where well-trained, pedantically precise engineers build the world's most advanced and reliable cars.
When the Chernobyl accident occurred, Germany's nuclear industry managed to convince itself, and German citizens, that aging reactors and incapable, sloppy engineers in Eastern Europe were to blame. Western reactors, or so the industry claimed, were more modern, better maintained and simply safer.
It is now clear how arrogant this self-assured attitude is. If an accident of this magnitude could happen in Japan, it can happen just as easily in Germany. All that's needed is the right chain of fatal circumstances. Fukushima is everywhere.
The 9/11 of the Nuclear Industry
It seems likely that politicians and scientists will take a much more skeptical view of nuclear energy from now on. This was evident in the agitated way German Environment Minister Norbert Röttgen, a member of Chancellor Angela Merkel's center-right Christian Democratic Union (CDU), reacted when he heard about the explosion at a reactor at the other end of the world. On Saturday morning, Röttgen told his wife that this was "an event that changes everything." They felt reminded of Sept. 11, 2001, the day of the terrorist attacks on New York and Washington.
A direct danger to Germany can be "practically ruled out," says Röttgen, adding that the most important thing now is to "express sympathy for Japan, establish clarity about the situation and offer help." Chancellor Merkel convened a crisis meeting on Saturday evening.
Röttgen reacted with irritation to the new nuclear debate that was already taking shape in Germany over the weekend. "I feel that this is uncalled for in this situation, and that it's really the wrong time," he said. Röttgen himself was unwilling to comment on the consequences for the planned extension of the life spans of nuclear power plants in Germany, calling it "a political discussion for another time."
The question of how long Germany's nuclear power plants should remain online has been the subject of a heated political debate in recent years. Last October, Germany's parliament approved an extension of the lifespans of the country's 17 nuclear power plants, effectively overturning a planned phase-out of nuclear power agreed on under the government of Merkel's predecessor, Gerhard Schröder. Under the new law, the plants will remain online for an average of an additional 12 years each, meaning Germany's last nuclear power plant is now slated to be shut down in 2035, rather than the 2021 deadline foreseen by the Schröder administration.
The law could still be overturned, however: The five German states controlled by the opposition center-left Social Democrats recently filed a complaint with the German Constitutional Court against the extension of the plants' operating lives.
Campaigning on an Anti-Nuclear Platform
The Greens, of course, disagree with Röttgen's assertion that this is not the time to talk about nuclear energy in Germany. They see the Japanese nuclear disaster as an opportunity to discuss one of their traditional core issues with new vehemence. Key elections are about to take place in the southwestern states of Baden-Württemberg and Rhineland-Palatinate. Recently, the Green Party has not been doing so well in the polls. Now it will campaign on an anti-nuclear platform, particularly as Baden-Württemberg Governor Stefan Mappus (CDU) is a strong supporter of nuclear power. Thomas Strobl, the CDU's general secretary in the state, is already planning ahead, saying: "We should not conduct an election campaign at the expense of people in Japan."
The Greens are unimpressed by such rhetoric. Jürgen Trittin, the former German environment minister and current Green Party co-floor leader in the Bundestag, feels validated in his skepticism about nuclear power. "Even a modern, technologically advanced country like Japan is not immune to the risks of a meltdown. The same applies to Germany, where we are even extending the life spans of especially unsafe nuclear reactors like Neckarwestheim," says Trittin. He points out that the accident in Japan also shows that extending life spans is irresponsible.
Renate Künast, who shares the chairmanship of the Green Party parliamentary group with Trittin, adds: "Nuclear power plants should not be located in metropolitan areas, and certainly not in earthquake zones. This also applies to Germany. Neckarwestheim, for example, is not quakeproof."
Volker Kauder, parliamentary floor leader in the Bundestag for the CDU and its Bavarian sister party, the Christian Social Union (CSU), has already made it clear that the two parties will continue to support extending plant life spans, despite the Fukushima accident. Deputy floor leader Michael Fuchs agrees: "Japan has completely different tectonic conditions from Germany. The accident there does not cast doubt on the extension of life spans for nuclear power plants here."
Key Issue in Germany
This is an old line of reasoning, but whether it can be sustained is questionable. Until now, the industry, the CDU/CSU and the FDP have insisted that German nuclear power plants were safe and that Germany could rely on its engineers. But the same thing was always equally true of Japan. Its engineers have the reputation of being as good as Germany's when it comes to building everything from automobiles to power plants. So if the Japanese cannot be relied upon to build reactors that can operate safely in their environment, what does this say about the Germans?
Hardly any other issue has had as strong an impact on the history of postwar Germany as nuclear power. And hardly any other country reacts with as much sensitivity to the risks of nuclear contamination. This is one of the reasons Germans founded an anti-nuclear party, the Green Party, which has since become firmly rooted in the political system.
Germany also has its own geography of opposition to nuclear power, including places such as Brokdorf, Kalkar, Wackersdorf and Gorleben, whose names have become symbols of the debate. German civil society has waged major battles against nuclear power, usually with words but sometimes with clubs, stones, water cannon and Molotov cocktails.
Resistance has even become a way of life for some people, like the activists who established the short-lived "Free Republic of Wendland" in 1980 near a planned nuclear waste repository in Gorleben in northern Germany. The movement has even coined a verb, "schottern," which refers to acts of sabotage against nuclear waste transports.
New Lease on Life for Anti-Nuclear Movement
When the Green Party formed a coalition government with the center-left Social Democratic Party (SPD) in 1998, it made a nuclear phase-out one of its top priorities, with the goal of shutting down all reactors by 2021. But when the CDU/CSU/FDP coalition came into power in 2009, it began discussing the extension of plants' life spans. The government feared an electricity shortfall if reactors were shut down and the burden shifted to renewable energy sources. Besides, politicians in the new government were thrilled to be able to reverse the hated legislation the SPD/Green Party had enacted before leaving office.
But it was precisely this about-face that generated new support for the anti-nuclear movement. Some 120,000 people took part in a human chain between the Brunsbüttel and Krümmel nuclear power plants near Hamburg. Old concerns about the supposed uncontrollability of this energy source had resurfaced.
The CDU/CSU was divided over the issue. A large segment of the parliamentary group headed by Volker Kauder favored extending life spans by 15 or more years, while Environment Minister Röttgen wanted to stop at 10. The two camps agreed on 12 years. The government decided to push through the law without involving the upper house of parliament, the Bundesrat, because the coalition parties lack a majority there. (Normally the Bundesrat would have to approve any law that affects the competencies of Germany's 16 states.) Germany's Federal Constitutional Court is now expected to examine whether the government's approach is compatible with the German constitution. This process, too, could be reinvigorated in response to pressure generated by the disaster in Japan.
In the past, a majority of Germans could be quickly mobilized against nuclear power whenever there was a reason to do so. Fukushima is a very significant reason, and it will make a deep impression on the German debate. The pro-nuclear parties, the CDU, CSU and FDP, will have to come up with new arguments to justify extending reactor life spans. The Greens could get a new boost, and the SPD, which once supported nuclear power but then reversed its policy, could very well find itself marginalized in a debate in which it lacks strong credentials.
Chancellor Merkel has also shown herself to be somewhat indecisive on this issue, as she has been with many other debates. As a physicist, she has a natural confidence in nuclear science and, therefore, in the nuclear industry. But as a politician she knows that supporting nuclear power is an unpopular position in Germany. As a result, she has kept a low profile and, with an eye to the strong opposition within the population, cautiously described nuclear power as a "bridge technology" to a future based on renewable energy, a technology that is acceptable for now but which makes little sense in the long term.
Countdown to a Nuclear Disaster
When the earth quaked, machines reacted more quickly than any people could have. Seismic sensors at the Fukushima Daiichi nuclear power plant detected the devastating shock waves on Friday within seconds. Two minutes later, at 2:48 p.m. local time, the reactor control system triggered a rapid automatic shutdown of the three reactors that were then in operation.
Everything went smoothly at first. Within seconds, the control rods were inserted between the fuel rods, thereby interrupting the nuclear chain reaction. This is precisely the way the system should operate. But then a serious problem occurred, initiating the countdown to a nuclear disaster.
Even after an emergency shutdown, a nuclear reactor still produces massive amounts of heat as the radioactive materials created during nuclear fission continue to decay. Unless engineers cool down a reactor for several days after it has been shut down, a core meltdown can occur, as was the case at the Three Mile Island nuclear power plant near Harrisburg, Pennsylvania, and at Chernobyl.
To prevent this from happening, pumps continued to put water through the cooling system at Fukushima. But then the power grid collapsed, as a result of the earthquake. The backup generators then went into operation.
'Like Trying to Drive a Car with No Engine'
Each reactor has three or four of these diesel generators. But when the tsunami arrived, the generators failed in two of the reactor units at Fukushima. The entire power plant site was flooded.
The engineers eventually managed to connect emergency batteries to the system. But these batteries are only designed to bridge a period of a few minutes so that, for example, the power supply can be switched from the grid to an internal source. These weak power sources managed to avert an immediate nuclear disaster on Friday evening.
It was an act of desperation, "like trying to drive a car with no engine solely using the battery," says Michael Sailer, the CEO of the Freiburg-based Öko Institut, an independent research institute. Sailer was chairman of the German Reactor Safety Commission for many years. "The batteries represent absolutely a last-ditch attempt," says Lothar Hahn, the former managing director of the Society for Reactor Safety.
While the Japanese engineers were struggling to avert looming disaster, reactor safety experts around the world were sitting in front of their computers and monitoring the progress of the chain reaction in horror. They sent each other emails, spoke on the phone and discussed the problem in special forums closed to the public. There was hardly any official information, but they all had their contacts with experts in Japan. "The situation is very serious," Hahn concluded immediately after learning that the cooling system had failed. "If this continues," an employee with the Japanese nuclear energy agency admitted on Friday evening, "we could, in a worst-case scenario, see a meltdown."
Apparently this is precisely what happened. Because the cooling pumps failed as a result of the loss of power, the water level fell in the reactor vessel. The fuel rods were reportedly only half-submerged in the cooling water, protruding from the water by almost a meter. As a result, they were partially destroyed and became overheated, just as an immersion heater can become overheated when it is removed from water.
In their desperation, the authorities authorized a controlled release of radioactively contaminated steam into the environment. Radioactivity levels within the plant rose to 1,000 times normal values, and radioactivity also became elevated on the entire site.
Reports that the pressure in the reactor container in Unit 1 had risen to six times atmospheric pressure seemed to herald impending disaster, because the reactor's protective shell can only withstand a pressure level amounting to eight times atmospheric pressure.
The situation at Fukushima escalated dramatically late Friday night. German nuclear expert Sailer likened the situation "to a disaster movie," as engineers desperately fought to gain control over the reactors. In the end, it was apparently a hopeless struggle.
The fuel elements had melted, at least partially, and apparently only the steel container housing the reactor and the containment layer were left, preventing the most highly radioactive materials from escaping. On Saturday evening local time, the plant's operators announced that they intended to flood the reactor with seawater, a last-ditch attempt to prevent the reactor vessel from melting. "They're basically trying to sink the reactor," says nuclear expert Mycle Schneider, who compiles the annual "World Nuclear Industry Status Report."
Echoes of Three Mile Island
The Fukushima accident resembles what happened at the Three Mile Island nuclear power plant near Harrisburg, Pennsylvania in 1979. On the morning of March 28, 1979, a blocked valve and various operating errors led to the loss of vast amounts of fluid from the cooling system for the plant's second reactor unit.
An automatic emergency shutdown stopped the chain reaction in the reactor core, as was the case in Japan last week. But the loss of cooling water resulted in a buildup of residual heat coming from the core material, melting some of the fissile material. Radioactive gases escaped into the environment, and it took experts five days to regain control over the reactor.
The Harrisburg accident was the first reactor catastrophe to generate worldwide questions about the safety of nuclear energy. But it was only after the Chernobyl disaster, the 25th anniversary of which is coming up, that many nations turned away from the high-risk technology.
The nuclear core in one of Chernobyl's reactors also melted on that fateful day, April 26, 1986. Ironically, it was during a safety inspection that operators lost control over reactor number four of the Chernobyl nuclear power plant, located near the city of Pripyat in present-day Ukraine.
As a result of various operating errors, the output of the reactor core rose to about 100 times its rated output. The resulting extreme heat destroyed the channels for the reactor's control rods, eliminating precisely the mechanism that is vital to preventing a nuclear fire. A disastrous series of chemical reactions led to the accumulation of an explosive mixture of gases beneath the roof of the reactor pressure vessel, which eventually ignited.
When the 1,000-ton concrete roof of the vessel was blown into the air, the reactor core caught fire. Large amounts of radioactive material, like iodine 131 and cesium 137, were released into the air and dispersed across large parts of the western Soviet Union and Western Europe.
The fallout descended onto about 200,000 square kilometers (77,220 square miles) of land. Because the Soviet government was unwilling to acknowledge the disaster for several days, valuable time was lost for such tasks as evacuating the nearby city of Pripyat. Many of the cleanup workers, known as "liquidators," were exposed to high doses of radiation in the first few days. The incidence of thyroid cancer has been elevated in the region surrounding the plant for years. The concrete containment shell that was hurriedly built around the reactor is beginning to crack and crumble.
Human error was to blame for the reactor accident in Ukraine. Fukushima could now serve as a warning that nuclear reactors cannot be protected with absolute certainty against the forces of nature, especially not when it comes to aging plants like Fukushima.
The Japanese reactor is "a historic relic," says Shaun Burnie, a British nuclear expert for Greenpeace who is very familiar with the reactors on Japan's east coast.
Burnie has visited the Fukushima reactors several times and has repeatedly worked in Japan. Reactors 1 and 2 at Fukushima Daiichi went into operation in the early 1970s, when safety standards were significantly more lax than they are today. They were built in an era when Volkswagen was building its Beetle without safety belts, airbags and headrests. The reactor that exploded on Saturday was in fact slated to be shut down soon.
Because the new construction of nuclear power plants is so expensive and difficult to defend politically, energy utilities in more and more countries are convincing governments to approve operating-life extensions that are much longer than those planned for German reactors. However, the renaissance of these aging power plants is now proving to be a dangerous game.
Limited Chance of Upgrade
Plant operators are trying to keep their reactors on line beyond their original 40-year life spans. The United States has extended licenses for many of its nuclear plants by 20 years, and European countries are following suit. But the safety technology in older plants can only be upgraded to a limited extent.
Eleven reactors in Japan had to be shut down on the day of the earthquake. Five were in a state of emergency because they could not be cooled properly. "This is a traumatic event. The international nuclear industry has tried to delay its demise with massive life span extensions," says nuclear expert Mycle Schneider. "The ancient systems at Fukushima have now illustrated the consequences. The industry will not survive this."
Burnie takes a similarly critical stance. "Never in a thousand years would you get a license for Fukushima today," he says. In the second-generation boiling water reactors that are still being used in the plant, the fuel rods float directly in the reactor vessel. Germany also has nuclear plants in the same category, including Brunsbüttel in the northern state of Schleswig-Holstein. Most of all, says Burnie, earthquake safety can only be improved to a limited extent. "The foundation consists of thousands of tons of concrete. That can't be upgraded."
Global Renaissance of Nuclear Power under Threat
The reactors at Fukushima Daiichi are sited directly on the shore, about 50 kilometers from the city of Sendai, which was devastated in the earthquake. Almost all of Japan's 55 nuclear power plants are built near the ocean, because they need a reliable source of large amounts of cooling water to operate. But this is precisely what makes them so vulnerable to tsunamis.
After the massive Indian Ocean tsunami hit Southeast Asia in 2004, nuclear regulators and plant operators recognized the risks for nuclear power plants. That tsunami flooded the cooling pumps for a reactor at India's Madras Atomic Power Station, but operators managed to shut down the reactor just in time to avert an accident. The wave also flooded a nearby construction site for a breeder reactor, where the Indians also intend to produce the explosive material plutonium. But apparently the Indian operators didn't learn much from the 2004 tsunami. After the site had been drained, they continued to build the reactor in the same spot.
On a more positive note, the International Atomic Energy Agency (IAEA) established the International Seismic Safety Centre two years ago. The center will serve as a forum for experts to exchange information and develop the highest possible standards. Japan is seen as one of the most active member nations, and for good reason. This isn't the first time an earthquake has threatened the safety of Japanese nuclear power plants. In 2007, for example, a magnitude 6.8 quake shook Japan's west coast. The epicenter was only 16 kilometers from Kashiwazaki-Kariwa, a seven-reactor complex and the world's largest nuclear power plant. Later it was revealed that one of the control rods had become jammed.
Bigger than Expected
The 2007 earthquake was also much more powerful than the engineers had expected. In fact, it was two-and-a-half times as powerful a quake as the reactor was designed to withstand. Today it is back in operation after having been upgraded. The same operator, Tokyo Electric Power Company (TEPCO), owns both Fukushima and Kashiwazaki-Kariwa.
Many nuclear experts are leery of TEPCO, partly because of its history. A scandal shook public confidence in the company 10 years ago, when it was discovered that TEPCO managers had doctored reports on leak tests performed during safety inspections in their nuclear power plants.
As a result of the TEPCO scandal, Japanese citizens have become increasingly mistrustful of their government and the nuclear industry. Japan generates about a third of its electricity with nuclear power and is about as dependent on reactors as France.
After the 2007 quake, the operators of a fuel reprocessing plant in Rokkasho-Mura were required to upgrade the complex, which was undergoing test operations at the time. The upgrade requirements virtually doubled the cost of the project, bringing it to a total of more than $20 billion -- an indication of how expensive earthquake safety can be.
After last week's tsunami, there was also a power failure at the Rokkasho nuclear facilities, and in the hours following the quake the plant's safety apparently depended entirely on the operation of diesel generators.
Whether the incidents in Fukushima will affect the boom in the construction of nuclear power plants in Asia remains to be seen. Nuclear power is currently undergoing a worldwide resurgence that would have been unthinkable in the years immediately after Chernobyl.
Asia's rapidly growing economies, China, South Korea and India, as well as Russia and the United States, are banking on electricity from nuclear power once again. The renaissance is a result of both the enormous thirst for energy in the emerging economies and the debate over the carbon dioxide emissions that contribute to global warming.
According to the IAEA, 29 countries currently operate 442 reactors, producing a total of 375 gigawatts of electricity. Another 65 plants are now under construction worldwide. Now that many believe that climate change has replaced nuclear disaster as the most significant threat to mankind, nuclear technology, with its low CO2 emissions, is gaining ground once again.
Sweden, for example, was long seen as setting an example of how to phase out nuclear energy. In the middle of last year, however, the Swedish parliament reversed a 30-year-old decision to move away from nuclear power. The new legislation could allow up to 10 new plants to be built, replacing the aging Forsmark, Ringhals and Oskarshamn plants.
In the United States, no applications to build new reactors were filed for three decades. Last year, President Barack Obama made billions in federal loan guarantees available for two planned complexes in Georgia. A project in South Carolina is already under construction.
China has 27 nuclear construction sites, while Russia is currently building 11 new reactors. Moscow even has plans to build small, floating reactors to supply electricity in the Russian Arctic.
End of the Dream of Cheap Energy
Most of all, however, more and more emerging economies, and even developing nations, are interested in nuclear technology. "We expect between 10 to 25 new countries to bring their first nuclear power plant online by 2030," IAEA Director General Yukiya Amano has said. According to Amano, a total of 65 countries, including 21 in Africa alone, have shown interest in the technology.
"Current forecasts suggest the world will see an increase in global energy consumption of over 50 percent by 2030," states an IAEA brochure with the telling title: "Considerations to Launch a Nuclear Power Program." According to the brochure, nuclear power plants can help ensure "access to affordable energy in many parts of the world."
The current situation suggests that the hopes of the nuclear lobby will be dashed. The fact that a nuclear disaster could occur in the land of robots and electric cars marks a turning point in the history of the technology.
There are metonyms for all of the accidents of the nuclear age, place names that have become symbols. Three Mile Island is one of them and so, of course, is Chernobyl.
There is no question that the name Fukushima will take on a similar significance. Fukushima will likely symbolize the end of the dream of manageable nuclear energy -- and the realization that we do not have this form of energy under control.
RALF BESTE, PHILIP BETHGE, KLAUS BRINKBÄUMER, DIRK KURBJUWEIT, CORDULA MEYER, RENÉ PFISTER, OLAF STAMPF, THILO THIELKE, WIELAND WAGNER