Efforts to develop nuclear energy have lengthy been stymied by fears of a serious nuclear meltdown. A brand new Chinese language reactor design is the primary full-scale demonstration that’s fully meltdown-proof.
Regardless of the speedy rise of renewable energy, many argue that nuclear energy nonetheless has an vital position to play within the race to decarbonize our provide of electrical energy. However incidents like Chernobyl and Fukushima have made folks understandably cautious.
The newest nuclear reactor designs are far safer than these of earlier generations, however they nonetheless carry the danger of a nuclear meltdown. This refers to when a plant’s cooling system fails, typically because of energy provides being reduce off, resulting in runaway overheating within the core. This could trigger an explosion that breaches containment models and spreads radioactive materials far and vast.
However now, researchers in China have carried out checks to show {that a} new form of reactor design is actually impervious to meltdowns. In a paper in Joule, they describe a take a look at during which they reduce energy to a reside nuclear plant—and the plant was capable of passively cool itself.
“The responses of nuclear energy and temperatures inside completely different reactor buildings present that the reactors will be cooled down naturally with out energetic intervention,” the authors write. “The outcomes of the checks manifest the existence of commercial-scale inherent security for the primary time.”
The researchers from Tsinghua College carried out the take a look at on the 200-megawatt Excessive-Temperature Gasoline-Cooled Reactor Pebble-Mattress Module (HTR-PM) in Shandong, which turned commercially operational final December. The plant’s novel design replaces the gas rods present in typical reactor designs with a lot of “pebbles.” Every of those is a few inches throughout and made up of graphite with a small quantity of uranium gas inside.
The strategy considerably reduces the power density of the reactor’s gas, making it simpler for warmth to dissipate naturally if cooling methods fail. Though small prototype reactors have been inbuilt China and Germany, a full-scale demonstration of the know-how’s security had but to occur.
To place the brand new reactor to the take a look at, the researchers intentionally reduce energy to each of the plant’s reactor modules and noticed the outcomes. Each modules cooled down naturally with none intervention in roughly 35 hours. The researchers declare that is proof the design is “inherently secure” and will considerably cut back necessities for security methods in future reactors.
The design does end in energy era prices roughly 20 p.c larger than typical reactors, the researchers admit. However they consider it will come down if and when the know-how goes into mass manufacturing.
China isn’t the one nation constructing such reactors. American firm X-Power has designed an 80-megawatt pebble-bed reactor known as the Xe-100 and is at present ready for a call on its license to function from the Nuclear Regulatory Fee.
Nonetheless, as New Scientist notes, it’s not attainable to retrofit present crops with this know-how, which implies the danger of meltdowns from older crops stays. And given the large quantity of money and time it sometimes takes to construct a nuclear energy plant, it’s unlikely the know-how will make up a major chunk of the world’s nuclear fleet anytime quickly.
However by proving it’s attainable to construct a meltdown-proof reactor, the researchers have disarmed one of many main arguments in opposition to utilizing nuclear power to tackle the climate crisis.
Picture Credit score: Tsinghua University
