The quest on how to get rid of excess heat in the development of fusion power plants has been answered in a class exercise at Massachusetts Institute of Technology (MIT) with industry researchers. Excess heat is one of the major challenges faced in fusion power plant development, which causes structural damage.
An innovative outlook to compact fusion reactors including the use of high-temperature superconducting magnets led to the new solution. This year, MIT launched various new research program based on this method and an independent startup company was also created to improve the concept. According to the researchers, a new design of the fusion power plant will enable to open the internal chamber of the device and replace its critical components, which is essential for the newly developed heat-reducing mechanism.
The recent approach is presented in a paper, published in Fusion Engineering and Design journal, authored by Adam Kuang, an MIT graduate student from that class. According to Professor Dennis White, director of Plasma Science and Fusion Center at MIT, release of heat from inside of a fusion power plant is equivalent to that of car’s exhaust system. In the new design, the heat-releasing pipe is relatively long and wide as compared to one in typical fusion plant, so as to make it highly effective in draining unwanted excess heat. However, it required a series of complex analysis and consideration of many possible design alternatives.
Fusion power plants holds a great promise to produce clean and abundant electricity but the years of research towards such plants have still not been able to develop device that produces power as much as it consumes. Earlier this year, MIT’s new approach to practical fusion power plant and several other innovative designs have made the goal achievable. But several challenges were left to be solved including a potential way to release the internal heat from plasma, which is an electrically charged and extremely hot material confined inside the device. The temperature of plasma reaches up to millions of degrees and no material in the device can withstand such heat.
In conventional fusion designs, plasma is held in place by powerful magnets to prevent its proximity to the interior walls of the device and another set of magnets is used to drain the excess heat by creating a side chamber known as divertors. However, these divertors are insufficient for the heat produced in the compact power plant. Further, in typical fusion design, secondary magnetic coils are placed outside the primary ones without precise control over the plasma shape.
ARC (Advanced, robust, and compact), a new MIT originated design, features magnets created in sections that are removable from the device. In the new arrangement, the secondary magnets can be placed inside the main coils, and by moving them closer to the plasma, the size can be significantly reduced. Decrease in the size of divertors could more precisely control the plasma, which aid in handling intense heat load. With development of the basic concept, there is plenty of room for development regarding heat management in fusion power plants, according to the researchers.