Context:
South Korea’s KSTAR fusion reactor set a new record by heating plasma at 100 million degrees Celsius for 48 seconds.
Key Points:
- Korea Superconducting Tokamak Advanced Research (KSTAR) achieved a breakthrough in nuclear fusion technology by sustaining plasma at 100 million degrees Celsius (seven times hotter than the Sun’s core temperature) for 48 seconds.
- This surpasses their previous record of 30 seconds in 2021.
- The ultimate goal for KSTAR is to maintain this plasma temperature for 300 seconds by 2026,
Significance:
- Major step towards developing clean and sustainable energy sources through nuclear fusion.
- The latest record “will greatly help secure the predicted performance in ITER operation in time and advance the commercialisation of fusion energy.
- This record demonstrates progress in overcoming technical hurdles to achieve sustained fusion reactions.
India’s Efforts:
- India also has active research programs in nuclear fusion through ITER (International Thermonuclear Experimental Reactor) project
- India’s first tokamak, Aditya, has been operational for over 30 years. It utilises copper coils
- SST-1 (Steady-State Tokamak-1) is India’s larger tokamak. Unlike Aditya, SST-1 uses superconducting magnet coils to achieve steady-state conditions with an operational pulse length goal of 1000 seconds.
Other countries’ efforts in nuclear fusion research:
- Japan: Beyond its participation in ITER, Japan boasts the JT-60SA tokamak, a powerful research reactor designed to test advanced plasma control technologies and materials needed for a future fusion power plant.
- China: China’s Experimental Advanced Superconducting Tokamak (EAST achieved a peak temperature of 288 million degrees Fahrenheit, which is over ten times hotter than the sun.
- China explores alternative approaches like the smaller, doughnut-shaped Spherical Tokamak Experiment (STEX) to study plasma confinement properties.
- China is also operating the HL-2A reactor as well as J-TEXT.
- China achieved the world’s First 403-Second Steady-State H-Mode Plasma in April 2023, demonstrating progress in sustaining a plasma state suitable for fusion reactions.
- USA: The United States has a robust fusion research program, with facilities like the National Ignition Facility (NIF) utilizing lasers to achieve fusion ignition (brief bursts of fusion energy). Additionally, private companies in the US are emerging, contributing to the development of more commercially-viable fusion reactors.
- Canada: Canada has a smaller but active fusion research program focusing on the development of spherical tokamaks, a variant of the traditional tokamak design.
Challenges :
- Maintaining fusion reactions for longer durations and achieving commercially viable energy production remains challenging
- Sustaining high temperatures has not been easy to demonstrate due to the unstable nature of the high-temperature plasma.
- The intense flux of high-energy neutrons and other particles generated during fusion reactions subject the reactor’s structural materials to extreme conditions. Finding materials capable of withstanding these conditions while maintaining structural integrity is a challenging task.
- Tritium, a radioactive isotope of hydrogen, is a key fuel for deuterium-tritium (D-T) fusion reactors. However, tritium is not naturally abundant and must be produced artificially..
Tokamak Technology
- A tokamak is a special machine shaped like a donut. It’s used to study nuclear fusion, which is like the process that powers the stars.
- Inside the tokamak, super-hot gas called plasma is trapped by strong magnets.
- Scientists use tokamaks to create a new source of energy that’s clean and endless, just like the power of the stars.
Working Principle:
- Plasma Formation: Tokamaks use powerful electromagnets to create a toroidal magnetic field that traps and heats the plasma.
- Plasma Heating: Additional heating systems, like neutral beam injection or radio waves, further elevate the plasma temperature to reach the required conditions for fusion (typically exceeding 100 million degrees Celsius).
- Plasma Confinement: The intricate magnetic field configuration within the tokamak confines the plasma, preventing it from touching the walls of the device and losing heat.
- Fusion Reactions: If successful, fusion reactions occur within the confined plasma, releasing energy in the form of heat.
- Energy Extraction: This generated heat can then be used to drive turbines and produce electricity.
What is Nuclear fusion?
It is a process where atomic nuclei of light elements, typically isotopes of hydrogen (deuterium and tritium), combine to form a heavier nucleus, releasing a tremendous amount of energy in the form of heat. This process is what powers the Sun and other stars.
- Reaction: Two lighter nuclei fuse to form a heavier one, with a small amount of mass being converted into energy according to Einstein’s famous equation E = mc².
- Requirements: Extremely high temperatures (over 100 million degrees Celsius) and pressures are needed to overcome the electrical repulsion between positively charged atomic nuclei and force them close enough to fuse.
- Benefits: Fusion has the potential to be a clean and sustainable energy source. It doesn’t produce greenhouse gases like fossil fuels and generates minimal radioactive waste compared to nuclear fission.
- Challenges: Achieving and sustaining controlled fusion reactions for long durations remains a significant hurdle. Developing commercially viable fusion reactors requires overcoming technical challenges in plasma confinement, heating, and energy extraction.
ITER project
- ITER stands for “International Thermonuclear Experimental Reactor.” It’s a massive scientific experiment designed to demonstrate the feasibility of fusion power.
- it is an international collaboration aimed at building the world’s largest tokamak, a type of fusion reactor, founded in 2007 in southern France (Saint-Paul-lez-Durance).
- ITER is a collaborative effort involving seven parties: the European Union, China, India, Japan, South Korea, Russia, and the United States.
- Its primary goal is to achieve the milestone of “ignition,” where the fusion reactions produce more energy than is needed to heat the plasma and sustain the reaction.
- It aims to showcase the potential of fusion as a safe, clean, and virtually limitless source of energy, with no greenhouse gas emissions or long-lived radioactive waste.
Conclusion:
The KSTAR breakthrough, alongside collaborative efforts such as the ITER project, underscores the global commitment to advancing fusion research for the potential realisation of safe, limitless energy production. While challenges remain, this achievement signifies a promising step towards harnessing the fusion power for practical energy needs.