All nuclear power plants are operated in a near-meltdown status. They operate at very high heat, relying on nuclear fission to boil water that produces steam to drive the turbines that generate electricity. Critically, the nuclear fuel is prevented from melting down through the steady circulation of coolants which are pushed through the cooling system using very high powered electric pumps.
If you stop the electric pumps, the coolant stops flowing and the fuel rods go critical (and then melt down). This is what happened in Fukushima, where the melted fuel rods dropped through the concrete floor of the containment vessels, unleashing enormous quantities of ionizing radiation into the surrounding environment. The full extent of the Fukushima contamination is not even known yet, as the facility is still emitting radiation.
It's crucial to understand that nuclear coolant pumps are usually driven by power from the electrical grid. They are not normally driven by power generated locally from the nuclear power plant itself. Instead, they're connected to the grid. In other words, even though nuclear power plants are generating megawatts of electricity for the grid, they are also dependant on the grid to run their own coolant pumps. If the grid goes down, the coolant pumps go down, too, which is why they are quickly switched to emergency backup power -- either generators or batteries.
As we learned with Fukushima, the on-site batteries can only drive the coolant pumps for around eight hours. After that, the nuclear facility is dependent on diesel generators (or sometimes propane) to run the pumps that circulate the coolant which prevents the whole site from going Chernobyl. And yet, critically, this depends on something rather obvious: The delivery of diesel fuel to the site. If diesel cannot be delivered, the generators can't be fired up and the coolant can't be circulated. When you grasp the importance of this supply line dependency, you will instantly understand why a single solar flare could unleash a nuclear holocaust across the planet.
When the generators fail and the coolant pumps stop pumping, nuclear fuel rods begin to melt through their containment rods, unleashing ungodly amounts of life-destroying radiation directly into the atmosphere. This is precisely why Japanese engineers worked so hard to reconnect the local power grid to the Fukushima facility after the tidal wave -- they needed to bring power back to the generators to run the pumps that circulate the coolant. This effort failed, of course, which is why Fukushima became such a nuclear disaster and released countless becquerels of radiation into the environment (with no end in sight).
And yet, despite the destruction we've already seen with Fukushima, U.S. nuclear power plants are nowhere near being prepared to handle sustained power grid failures. As IBtimes reports:
"Last month, the Nuclear Regulatory Commission said U.S. plants affected by a blackout should be able to cope without electricity for at least eight hours and should have procedures to keep the reactor and spent-fuel pool cool for 72 hours. Nuclear plants depend on standby batteries and backup diesel generators. Most standby power systems would continue to function after a severe solar storm, but supplying the standby power systems with adequate fuel, when the main power grids are offline for years, could become a very critical problem. If the spent fuel rod pools at the country's 104 nuclear power plants lose their connection to the power grid, the current regulations aren't sufficient to guarantee those pools won't boil over -- exposing the hot, zirconium-clad rods and sparking fires that would release deadly radiation."
If you stop the electric pumps, the coolant stops flowing and the fuel rods go critical (and then melt down). This is what happened in Fukushima, where the melted fuel rods dropped through the concrete floor of the containment vessels, unleashing enormous quantities of ionizing radiation into the surrounding environment. The full extent of the Fukushima contamination is not even known yet, as the facility is still emitting radiation.
It's crucial to understand that nuclear coolant pumps are usually driven by power from the electrical grid. They are not normally driven by power generated locally from the nuclear power plant itself. Instead, they're connected to the grid. In other words, even though nuclear power plants are generating megawatts of electricity for the grid, they are also dependant on the grid to run their own coolant pumps. If the grid goes down, the coolant pumps go down, too, which is why they are quickly switched to emergency backup power -- either generators or batteries.
As we learned with Fukushima, the on-site batteries can only drive the coolant pumps for around eight hours. After that, the nuclear facility is dependent on diesel generators (or sometimes propane) to run the pumps that circulate the coolant which prevents the whole site from going Chernobyl. And yet, critically, this depends on something rather obvious: The delivery of diesel fuel to the site. If diesel cannot be delivered, the generators can't be fired up and the coolant can't be circulated. When you grasp the importance of this supply line dependency, you will instantly understand why a single solar flare could unleash a nuclear holocaust across the planet.
When the generators fail and the coolant pumps stop pumping, nuclear fuel rods begin to melt through their containment rods, unleashing ungodly amounts of life-destroying radiation directly into the atmosphere. This is precisely why Japanese engineers worked so hard to reconnect the local power grid to the Fukushima facility after the tidal wave -- they needed to bring power back to the generators to run the pumps that circulate the coolant. This effort failed, of course, which is why Fukushima became such a nuclear disaster and released countless becquerels of radiation into the environment (with no end in sight).
And yet, despite the destruction we've already seen with Fukushima, U.S. nuclear power plants are nowhere near being prepared to handle sustained power grid failures. As IBtimes reports:
"Last month, the Nuclear Regulatory Commission said U.S. plants affected by a blackout should be able to cope without electricity for at least eight hours and should have procedures to keep the reactor and spent-fuel pool cool for 72 hours. Nuclear plants depend on standby batteries and backup diesel generators. Most standby power systems would continue to function after a severe solar storm, but supplying the standby power systems with adequate fuel, when the main power grids are offline for years, could become a very critical problem. If the spent fuel rod pools at the country's 104 nuclear power plants lose their connection to the power grid, the current regulations aren't sufficient to guarantee those pools won't boil over -- exposing the hot, zirconium-clad rods and sparking fires that would release deadly radiation."
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