Fusion energy may not be too far away

Subject :Science and Technology

Context:

The ‘breakthrough’ announced by the US National Ignition Facility has focused the spotlight on nuclear fusion. NIF reported a net energy gain (more output than input), which is deduced to have come from two nuclei of hydrogen atoms fusing to form a helium nucleus.

More in news:

Commonwealth Fusion Systems (CFS) is building the world’s first fusion device that produces plasmas which generate more energy than they consume, becoming the world’s first net-energy fusion machine. The device, named SPARC, is for demonstration but a commercial plant is expected to follow.
- Headquartered in Cambridge, Massachusetts, USA, Commonwealth Fusion Systems (CFS) was set up in 2018.
CFS aims to build the demonstration plant, SPARC, by 2025 and the commercial plant by 2030.

Types of nuclear fusion:

Within nuclear fusion, there are two segments — hot and cold.
While NIF, ITER and CFS work on hot fusion.
- Hot fusion is where the temperature needs to be six times hotter than the core of the sun.

Low-energy nuclear reaction (cold fusion):
- Cold fusion is a hypothesized type of nuclear reaction that would occur at, or near, room temperature.
- There is currently no accepted theoretical model that would allow cold fusion to occur.
- In 1989, two electrochemists, Martin Fleischmann and Stanley Pons, reported that their apparatus had produced anomalous heat (“excess heat”) of a magnitude they asserted would defy explanation except in terms of nuclear processes.
- They further reported measuring small amounts of nuclear reaction byproducts, including neutrons and
- The small tabletop experiment involved electrolysis of heavy water on the surface of a palladium (Pd) electrode.

Comparison of Cold and Hot Fusion:

Cold Fusion

Hot Fusion

1. Occurs only in special solids.

2. Responds to modest energy but not required.

3. Uses protium (H) or Deuterium (D).

4. Makes mostly helium (He) when D is used.

5. Produces insignificant radiation.

6. Can be initiated in simple devices at high O/I levels.

7. It is a theoretical phenomenon.

1. Occurs in plasma or when enough energy is applied.

2. Requires high energy.

3. Uses tritium and deuterium

4. Makes helium and neutron

5. Produces significant radiation

6. Requires a huge machine to produce high O/I levels.

7. Recently net positive energy has been produced using hot nuclear fusion technology.