The tsunami that knocked out critical back-up cooling power at the Fukushima Daiichi nuclear power plant on March 11, 2011, is still, in a sense, rolling over Japan\'s energy system. Only two of the nation\'s 54 nuclear power plants are still in operation, and by the end of next month, those will be shut down, too, extinguishing the source that provided one-third of the electricity for the world\'s third-largest national economy before the Tohoku earthquake. One by one, local government officials have used the power they have under Japanese law to halt nuclear generation, by refusing to sign off on restart of any reactor after its routine maintenance shutdown. Until and unless the national government can convince prefecture officials of the safety of atomic energy in the earthquake- and tsunami-prone country, Japan faces a severe electricity shortfall that will manifest itself when hot, humid summer weather ratchets up demand for power. With no domestic fossil fuel sources to take the place of nuclear, Japan is relying ever more heavily on expensive imports of oil and liquefied natural gas. But that has left the island nation vulnerable to still another energy risk: Nearly 70 percent of Japan\'s oil imports last year traveled by tanker through the Strait of Hormuz. If Iran\'s conflict with the West over its nuclear program escalates to disrupt Middle East oil shipments, it would be yet another blow to the struggling Japanese economy. For now the hope is that extensive energy conservation measures, which allowed Japan to ride out a significant energy shortfall last summer, will see it through the more severe scarcity ahead. But the bigger question is how the nation, in addition to tackling the decades-long radiation clean-up effort ahead at Fukushima Daiichi, will rebuild the needed trust in private and public institutions as it charts a new course to fueling its future. “The big picture is the shattering of public confidence, not just in the nuclear program, but also in the government itself,\" says Sheila Smith, senior fellow for Japan studies at the Council on Foreign Relations in Washington, D.C. \"The Japanese public is deeply shattered both by the magnitude of the disaster and by past and present government\'s management of these power plants, and larger questions about public safety. There\'s a lot of ‘mea culpa\' . . . a sense that ‘We ought to have asked more questions, and pushed harder for more openness and accountability.\' \" After the Deluge Before the earthquake, the size of Japan\'s nuclear power fleet rivaled only those of the United States and France. It was home to the largest atomic plant in the world, Kashiwazaki-Kariwa in Niigata Prefecture on the west coast, and though that plant had been severely damaged and partially idled by a 6.8-magnitude earthquake in 2007, the nation\'s significant seismic risks had not dimmed its ambition for nuclear power expansion. To fuel its future growth with fewer greenhouse gas emissions, Japan had committed to ratcheting up the share of nuclear power in its electricity supply, from 30 percent to 40 percent by 2017, and to 50 percent by 2030. (In contrast, nuclear power provides just 20 percent of electricity in the United States.) Those plans began to unravel at 2:46 p.m. Japan standard time last March 11, with a 9.0-magnitude earthquake 81 miles (130 kilometers) east of Sendai in the Pacific Ocean. The massive tremor, the most powerful ever to have been recorded in Japan, triggered the automatic shutdown of 11 nuclear power plants at four sites along the northeast coast. That protective measure proceeded as planned, but nuclear plants need a small amount of constant power even after fission has stopped. Diesel generators switched on to run the cooling systems that control the decay heat of the plants\' nuclear fuel. (Related: \"Photos: Japan\'s Reactors Before And After\" and Japan Reactor Crisis: Satellite Pictures Reveal Damage\") About 40 minutes after the quake, the tsunami hit, inundating Fukushima Daichi and crippling its crucial diesel back-up power system. The water\'s height was estimated at more than 45 feet (14 meters), breaching the site\'s flood protections by some 27 feet (8 meters). Amid already widespread destruction and the loss of tens of thousands of lives, Fukushima Daiichi became a second disaster epicenter. Plant workers labored in near-total darkness to prevent a meltdown, with limited instrument readings and controls. Their efforts could not prevent the fuel damage, buildup of hydrogen gas, or explosions that blasted holes in the thick concrete walls in the first days of the crisis. (Related: \"Photos: Rare Look Inside Fukushima Daiichi\") It took weeks to stabilize the plant, but years of decontamination effort lie ahead. More than 70,000 people who lived within a 12.4 mile (20-kilometer) radius remain evacuated, as Japan cleans up the radioactive fallout from a nuclear accident second only to the 1986 Chernobyl explosion in Ukraine. (Related Photos: \"The Nuclear Cleanup Struggle at Fukushima\") (Related:\"Japan\'s Nuclear Refugees\") Prime Minister Yoshihiko Noda has said the government will spend at least 1 trillion yen ($13 billion) on the decontamination effort around the permanently shuttered plant. But the crisis of confidence in nuclear energy has spread far beyond Fukushima. Noda\'s predecessor, Naoto Kan, said that Japan should pursue a nuclear-free future before he resigned last August due to a precipitous fall in popularity for his government. Noda, in contrast, has pledged to boost the safety of the nation\'s nuclear plants, while pursuing alternative energy. But only 19 nuclear plants were still in operation when Noda took office in September, and 17 have closed since then. Only one unit of Kashiwazaki-Kariwa and another reactor to the north on the Sea of Japan, at Tomari on the island of Hokkaido, remain in service. After they are shut down for scheduled safety checks this spring, Japanese officials expect that they will be kept out of service too, with local authorities unwilling to certify restart. Without any nuclear plants online, Japan faces a summer when peak electricity demand likely will exceed supply by 15 percent, observers say. Last summer, Japan weathered a shortfall of electricity with a concerted national effort to curb demand. It ramped up a campaign it has been promoting since 2005 to cut air-conditioning in offices, calling for temperatures to be set at 28°C (85°F), when summer high temperatures in Tokyo can surpass 30°C (86°F) with high humidity. Companies also shifted work to early hours or weekends, and took other steps such as deactivating elevators and reducing use of printers and copiers. Smith recalls being in Japan last summer in buildings where neon signs were dimmed, overhead fluorescent lights turned off, and people in government offices used flashlights to make their way along dark corridors. (Related: \"Energy-Short Japan Eyes Renewable Future, Savings Now\") “It was a massive national effort,\" she says.\"The public understands conservation is going to have to be a part of the answer, but I\'m not sure those draconian kind of cutbacks they made last year are sustainable over the long term.\" So Japan\'s national government and private electric power companies are working to boost protections at nuclear power plants in a bid to win back public confidence, to pave the way for the reopening of the facilities. In many ways, the steps being taken in Japan are similar to those under way at other nuclear plants around the world, with a new focus on robust and multiple systems to withstand an extended outage of power from all units at a site. “That has probably been the largest change in the industry\'s approach, to think about events that can impact more than one unit,\" says Neil Wilmshurst, vice president of the nuclear sector at the U.S. Electric Power Research Institute (EPRI). (Related: \"Ten Oldest U.S. Nuclear Plants-Post-Japan Risks\") But in Japan, some of the new safety measures have been extraordinary. At Hamaoka power plant in Omaezaki, on the Pacific coast some 125 miles (200 kilometers) southwest of Tokyo, Chuba Electric Company is building a $1.3 billion, 1-mile (1.6-kilometer) flood wall nearly 60 feet (18 meters) high. Due for completion late this year, it would not only surpass the height of the wave that hit Fukushima, it would be 33 feet (10 meters) higher than the highest waves expected at Hamaoka in the event of three major simultaneous earthquakes, Chuba has said. The risks at Hamaoka have especially stirred public concern because of its location on the infamous fault line that seismologists believe is overdue for the\"Big One,\" the feared\"Tokai earthquake.\" Economic Impact But weighing against anxiety about the safety of the nuclear power plants is the economic incentive to reopen them. Tax revenues from the plants bolster local governments. And the operation and maintenance of the facilities provides jobs.\"It\'s a major employment driver,\" says Jane Nakano, a fellow in the Center for Strategic and International Studies\' energy and national security program.\"You can\'t overlook the communities that are not anti-restart. And even the local communities that are apprehensive, they still need jobs.\" Electricity shortages also increase the threat that even more manufacturing will flee to China, increasing an exodus well under way before the earthquake, Nakano said.\"It will be interesting to look back in 10 or 15 years, to see what the studies say about Fukushima and its impact on Japan\'s efforts to stay competitive,\" she says. For the nation, an added burden is the increased foreign oil and natural gas dependence to generate power in place of nuclear energy. As tensions have increased in the Middle East, Japan has worked to diversify its sources of oil. It has dramatically increased imports from Vietnam and Indonesia, two countries that provide a grade of crude especially suited to burning for electricity. Foreign Minister Koichiro Gemba last month sought to reassure the public that the nation could withstand a closure of the Strait of Hormuz. It had stockpiled oil reserves equivalent to about 200 days worth of consumption, and enough liquefied natural gas (LNG) to last 70 days, he said. (Related:\"Iran\'s Undisputed Weapon: Power to Block the Strait of Hormuz\") The cost of increased imports will reverberate throughout the economy. Japan pays about $18 per million BTU for imported LNG, more than four times the price U.S. consumers pay for domestically produced natural gas. In a presentation last December at the Howard Baker Forum\'s U.S.-Japan Roundtable on Nuclear Energy Cooperation, Takuya Hattori, president of the Japan Atomic Industrial Forum\'s International Cooperation Center, estimated that the cost to purchase an additional 20 million tons of LNG due to make up for the loss of the nuclear power plant outages will be $44 billion (3.4 trillion yen). There has been much public pressure and government commitment to expand renewable energy in Japan. Although the country does not have large available land area for massive wind and solar facilities, there have been drives for rooftop solar and research into advancing the technology. (Related:\"Pictures: A New Hub for Solar Power Blooms in Japan\") But renewable power cannot ramp up quickly enough to replace the immediate nuclear energy shortfall. Japan\'s only short-term option is to hold down demand and increase imports while working to reassure the public of the safety of its nuclear fleet.\"The Japanese people have pulled together, and shown the remarkable extent they\'ve gone to reduce demand in the face of uncertainty in supply,\" Wilmshurst said.\"It will be a matter of time before it is figured out exactly what the future of the electric industry in Japan is.\"