Brief Context
Context Scientists have found that investors are overestimating the experience rate of nuclear fusion. About The experience rate of nuclear fusion refers to how the cost or efficiency of fusion technology improves with accumulated experience. Current nuclear fusion models often assume experience rates between 8% and 20%.
Source Content
Syllabus: GS3/Science and Technology
Context
- Scientists have found that investors are overestimating the experience rate of nuclear fusion.
About
- The experience rate of nuclear fusion refers to how the cost or efficiency of fusion technology improves with accumulated experience.
- Current nuclear fusion models often assume experience rates between 8% and 20%.
- After examining the unit size, design complexity, and need for customisation, Scientists found that fusion power plants will likely see experience rates of 2% to 8%.
What is Nuclear Fusion?
- Nuclear fusion is the process by which two light atomic nuclei combine to form a single heavier one while releasing massive amounts of energy.
- Fusion reactions take place in a state of matter called plasma — a hot, charged gas made of positive ions and free-moving electrons with unique properties distinct from solids, liquids or gases.
- The sun, along with all other stars, is powered by this reaction.
- Process: The Deuterium (H-2) and Tritium (H-3) atoms are combined to form Helium (He-4). A free and fast neutron is also released as a result.
- The neutron is powered by the kinetic energy converted from the ‘extra’ mass left over after the combination of lighter nuclei of deuterium and tritium occurs.
Challenges of Fusion Energy
- Extreme temperature requirement: It needs ~100 million °C to initiate and sustain fusion.
- Plasma instability: Hot plasma is highly unstable and difficult to confine.
- Magnetic confinement complexity: Advanced systems like Tokamak are technically challenging and costly.
- Net energy gain issue: Achieving sustained energy output greater than input is still difficult.
- Material degradation: Reactor walls face intense neutron bombardment and heat damage.
- High cost & long gestation: Projects like ITER require massive funding and decades of development.
Significance of Fusion Energy
- Clean Energy: Nuclear fusion just like fission does not emit carbon dioxide or other greenhouse gases into the atmosphere, so it could be a long-term source of low-carbon electricity from the second half of this century onwards.
- More Efficient: Fusion could generate four times more energy per kilogram of fuel than fission (used in nuclear power plants) and nearly four million times more energy than burning oil or coal.
- Fusion fuel is plentiful and easily accessible: Deuterium can be extracted inexpensively from seawater, and tritium can potentially be produced from the reaction of fusion-generated neutrons with naturally abundant lithium.
- These fuel supplies would last for millions of years.
- Safer to Use: Future fusion reactors are also intrinsically safe and are not expected to produce high activity or long-lived nuclear waste.
- Furthermore, as the fusion process is difficult to start and maintain, there is no risk of a runaway reaction and meltdown.
Difference between Nuclear Fusion and Fission
Source: TH