Part 2 of 2 Parts (Please read Part 1 first)
    Previous attempts to exceed the Greenwald limit often resulted in reduced plasma confinement or complete loss of fusion reactions. The success of the GA team in achieving both high density and strong confinement allows new possibilities for designing more efficient and reliable fusion reactors.
     Another major problem for fusion reactors like tokamaks is controlling the instabilities that can develop within the plasma. These instabilities, if not dealt with, can disrupt the reactor’s operations and damage its components. The recent research from GA not only surpassed the Greenwald limit but also hinted at potential methods for managing these instabilities.
     The researchers mentioned a “synergy” between achieving high plasma density and maintaining high confinement, which could lead to a more stable state for the plasma. This indicates that it may be possible to achieve conditions where the plasma remains stable at even higher densities. This would reduce the risk of disruptions that have previously been a major challenge.
     Fusion reactors also have to deal with the challenge of balancing temperatures within the plasma. To initiate fusion, the core of the plasma must reach hundreds of millions of degrees Celsius. The outer edge, which comes into contact with the reactor walls, needs to be kept much cooler to prevent damage. Achieving and maintaining this balance is critical for the reactor’s efficiency and longevity.
      The research from GA provides new insights into how to maintain this temperature gradient effectively. Understanding the physics that governs the temperature distribution within the plasma is critical in designing reactors that are both compact and efficient. These insights bring engineers closer to solving one of the critical challenges that have held back the development of practical fusion power.
     The breakthrough by the GA team represents an important step towards achieving commercially viable fusion power. By breaking through the Greenwald limit and demonstrating improved plasma confinement, they have provided new opportunities for more efficient fusion energy production. This development could allow for the creation of fusion reactors that are capable of operating under conditions necessary for sustained and efficient power generation.
     While there is still a great deal of work to be done before fusion power becomes a reality, the progress made by these researchers is a clear indication that we are moving in the right direction. Achieving stable, high-density plasma in a controlled environment is one of the key milestones on the road to fusion energy. The recent advances are an encouraging sign that the dream of clean, limitless energy may one day become a reality.
     Nuclear fusion is a promising source of clean and sustainable energy. However, creating and maintaining the conditions for fusion is extremely challenging. Tokamak reactors utilize magnetic fields to confine the hot plasma needed for fusion, but plasma density is limited by the Greenwald limit, beyond which instabilities disrupt confinement. The GA team has successfully surpassed the Greenwald limit, achieving plasma density twenty percent higher while maintaining superior confinement. This breakthrough addresses a major obstacle for practical fusion reactors, making it possible to achieve and maintain conditions required for efficient fusion. The research also provides insights into managing plasma instabilities and balancing core and edge temperatures which are critical for reactor efficiency. These advancements mark a significant step towards the creation of commercially viable fusion reactors.

     The Deep Atomic (DA) MK60 small modular reactor (SMR) design has been developed specifically to provide power and cooling to data centers.
     The MK60 is a light water SMR incorporating multiple passive safety systems. DA states that it is “compact, scalable, and built on a foundation of proven technology”. Each unit generates up to sixty megawatts and provides an additional sixty megawatts of cooling capacity through its “integrated data center-centric design approach”.
     DA is headquartered in Zurich, Switzerland. It says that the reactor is well-suited to various types of data centers, including those supporting traditional cloud services, cryptocurrency operations, and AI applications.
     William Theron is the founder of DA and CEO. He says, “Data centers are the backbone of digital innovation, but their massive energy needs have become the critical bottleneck blocking growth.”
     The MK60 is said to offer data center operators a scalable power solution that can be deployed in various locations, including areas with limited grid access. The reactor can be sited closer to urban areas due to its advanced safety features.
     Theron said, “It’s designed to be installed on-site at data centers, delivering reliable zero-carbon electricity and energy-efficient cooling, thereby significantly reducing carbon footprints, and helping data centers meet their increasingly stringent sustainability goals.”.
     Freddy Mondale is the Head of Engineering for DA. He noted that many areas were struggling to provide the amounts of power that new data centers require. “Our on-site reactors bypass these grid limitations, allowing data centers to be built in optimal locations without straining existing infrastructure.”
     Mondale says that a sixty megawatts reactor with additional sixty megawatts of cooling capacity “hits a sweet spot for data centers. It’s large enough to power significant compute infrastructure, yet small enough to allow for modular deployment and scaling”.
     Mondale added that “The MK60 can be deployed in multiples, allowing scalability from 60 MW up to over 1 GW to meet growing energy demands.”
     DA says it has already begun dialogues with regulators and potential customers as it moves forward with development. The company is seeking partnerships with data center operators and other investors who are “looking towards the future of sustainable digital infrastructure”.
     DA’s announcement of the MK60 follows several announcements by global tech giants related to nuclear energy.
     Microsoft announced last September that it had signed a twenty-year power purchase agreement with Constellation that will see the restart of Three Mile Island Unit 1. Google announced last week it had agreed to purchase energy from Kairos Power in a deal that would support the first commercial deployment of its fluoride salt-cooled high-temperature advanced SMRs by 2030 and aim for a fleet totaling five hundred megawatts of capacity by 2035. The following day, Amazon announced a series of agreements in which it will acquire a stake in advanced nuclear reactor developer X-energy and roll out its Xe-100 advanced SMR initially at a project in Washington State.
     Meanwhile, the head of Japanese cloud-based gaming services provider Ubitus KK has said that it is planning to build a new data center and is specifically looking at areas with nearby nuclear power plants to provide the required power.

     An international team is constructing a revolutionary nuclear fusion reactor in Spain called SMall Aspect Ratio Tokamak (SMART) to address future energy demands. Academics are currently publishing a series of papers describing the cutting-edge technology that powers SMART.
     The Princeton Plasma Physics Laboratory (PPPL) is collaborating with the Spanish University of Seville on the design and development of a new fusion reactor design.
     Jack Berkery is the principal investigator for the PPPL collaboration with SMART. He said that “The SMART project is a great example of us all working together to solve the challenges presented by fusion and teaching the next generation what we have already learned. We have to all do this together or it’s not going to happen.” Together with PPPL’s experience in magnetics and sensor systems, the SMART project benefits from PPPL computer codes.
     Fusion reactors work on the same principle that powers the stars. They combine hydrogen and other light elements to produce helium and release enormous amounts of energy. In contrast to fission-based nuclear energy reactors currently in use, fusion offers the potential to produce huge amounts of energy with less waste and risk.
     Previous attempts to produce fusion have resulted in more energy being used than produced. Reaching a net positive energy output has remained a challenging task. When a team from the U.S. managed to deliver seven tenths of a megajoules of energy in 2022, it was considered a tremendous feat.
     Although fusion energy is still years away, the SMART project intends to move closer to that goal. SMART is a new spherical tokamak fusion reactor that explores negative versus positive triangularity prospects. SMART has a unique design that incorporates a tokamak cross-section and negative triangularity
     Manuel Garcia-Munoz is a professor at the University of Seville. According to him, a negative triangularity could provide improved performance. He added that “It’s a potential game changer with attractive fusion performance and power handling for future compact fusion reactors. Negative triangularity has a lower level of fluctuations inside the plasma, but it also has a larger divertor area to distribute the heat exhaust.”
     The novel structure increases performance by suppressing plasma instabilities, which may cause energy loss and possibly even damage to the walls of the nuclear reactor. Garcia-Munoz explained that “The idea was to put together technologies that were already established: a spherical tokamak and negative triangularity, making SMART the first of its kind. It turns out it was a fantastic idea.” 
     Researchers are currently investigating advanced diagnostic methods to track plasma conditions in the experiments. The tools created in collaboration with PPPL will evaluate the plasma’s stability and impurity. This will guarantee a more effective fusion process, noted the press release from Monday.
     In the search for sustainable energy solutions, the SMART project offers the promise of revolutionizing energy generation. The project hopes to achieve first plasma by late 2024. And, as global cooperation continues, the goal of using fusion energy to supply huge amounts of power the grid is getting closer to reality.