|Karla Lant reminds that in 2011, the Great Tahoku Earthquake triggered a 15-meter-high tsunami wave that hammered the eastern coast of Japan. The wave flooded many buildings, and disabled the cooling and power supply of three reactors, causing the nuclear fuel rods to overheat at the Fukushima Daiichi plant. With the power out, the emergency cooling generators could not function, and explosions (from accumulated boiling water creating hydrogen) began in the reactor containment buildings. This in turn caused nuclear material to leak out into the atmosphere. As emergency response system failed, all three cores melted down almost completely within the first three days.|
According to the World Nuclear Association, the accident was rated 7 on the INES scale, due to high radioactive releases. The meltdown released 940 PBq of radioactive material, about 15% to 18% of what Chernobyl released, which was about 5,200 PBq. The combined total of confirmed deaths and missing persons from the tsunami events was more than 22,000, but all of these people were all lost due to the natural disaster and by the resulting health conditions afterwards. There were no deaths caused by the meltdown itself or of anyone irradiated.
The Japanese government ordered 154,000 people to abandon their homes immediately following the accident because of initial concerns about radiation. By 2016, most of these people, about 97,000, remained displaced (homeless). The earthquake was by far the most expensive disaster in history, the economic damages of this disaster are estimated at about $235 billion (caused by tsunami plus damage to plant?).
But nuclear plants generate clean energy without greenhouse emissions, preventing around 80,000 deaths caused by air pollution annually. Nuclear is also safer than all other sources of energy. Natural gas is 30% more dangerous (gas-line leaks), coal is 270% more dangerous (methane-gas explosions), and hydroelectric is 460% more dangerous (dam failures).