What is Fusion?
Fusion is the process where two light atomic nuclei combine to form a heavier nucleus. It's the same power source that fuels the sun, releasing vast amounts of energy through Einstein's equation, E=mc².
Fusion vs Fission
Unlike fission, which splits heavy atoms to release energy, fusion joins atoms together. While fission generates long-lived radioactive waste, fusion's byproducts are generally less radioactive and short-lived.
Fusion's Fuel: Isotopes of Hydrogen
The primary fuels for fusion are deuterium and tritium, heavier isotopes of hydrogen. Deuterium is abundantly found in seawater, while tritium can be bred from lithium, which is found in the Earth's crust.
The Challenge of Containment
To achieve fusion, temperatures must exceed 100 million degrees Celsius, hotter than the sun's core. At these temperatures, matter exists as plasma and requires sophisticated magnetic confinement to prevent it from melting any container.
Inertial Confinement Fusion
An alternative to magnetic confinement is inertial confinement, where fuel pellets are bombarded with intense laser beams or ion beams, compressing and heating the fuel to fusion conditions rapidly.
Fusion: Energy's Holy Grail
Fusion promises a nearly limitless supply of energy with minimal environmental impact. It produces no greenhouse gases during operation and has a fuel supply that could last for millions of years.
Current Fusion Experiments
The largest fusion experiment is the International Thermonuclear Experimental Reactor (ITER) in France. It aims to demonstrate the feasibility of fusion as a large-scale, carbon-free energy source by the 2040s.