Nuclear fusion may still be decades away, but latest breakthrough could accelerate its development
Nuclear fusion holds great promise as a clean and abundant source of energy that could power the world. Today, fusion researchers at a national laboratory in the United States have achieved something that physicists have been working on for decades, a process known as “ignition”.
This step involves extracting more energy from the fusion reactions than is put up by a laser.
But how close are we to producing energy from fusion that can power people’s homes? While the ignition is only a proof of principle and the first step in a very long process, other developments are also underway and together they could generate new enthusiasm to make fusion a reality. practice.
First, it is important to recognize that the latest result is indeed a real milestone.
Researchers at the National Ignition Facility (NIF) in California have fired the world’s largest laser at a hydrogen-filled capsule, causing it to implode and triggering fusion reactions that mimic what happens in the Sun.
The fusion energy released by the implosion was greater than that contributed by the laser, a huge achievement considering that just a few years ago the NIF laser could only extract about a thousandth of the energy that he had injected.
However, about 10,000 times more energy had to be injected into the laser than it produced in light energy.
It can only be run once per day. And each target is so well designed that each one costs thousands of dollars.
To produce a reactor for a working power plant, you would need a laser that produces light energy with much higher efficiency (a few tens of percent) and successfully fires targets ten times per second, each target costing around pennies.
Additionally, each laser shot should produce many times – maybe 100 times – more energy than was put in.
Very little research has been done on fusion “reactors”, where the neutrons from the reactions would help drive a steam turbine to generate electricity. But there are other reasons for hope.
First, while the NIF took more than a decade to achieve ignition, during the same period scientists independently developed new lasers.
These use electronic devices called diodes to transfer energy to the laser and are very, very efficient, converting a good fraction of the mains electricity into laser light.
Prototype versions of these lasers have been proven to operate at the speed of 10 times per second, which would be necessary for them to be useful in fusion.
These lasers are not yet of the size required for fusion, but the technology is proven and the UK is leading in this type of research.
Additionally, the fusion approach used by NIF scientists has some well-known inherent inefficiencies, and there are several other ideas that could be much more effective.
No one is absolutely certain that these other ideas would work, as they have their own issues and have never been tested on a large scale.
To do this would require hundreds of millions of dollars of investment for each of them with no guarantee of success (otherwise it would not be research).
However, a new wind is now blowing: the private sector.
Various very long-term funds have started investing in new start-ups that tout fusion as a commercially viable source of energy.
Given that it is private industry that has revolutionized the electric car market (and the rocket industry), perhaps this sector could also give fusion the “boost” it needs.
Private companies can work much faster than governments and pivot quickly to adopt new ideas when needed.
Estimates of total private funding in the sector now exceed $2 billion (about Rs 16,500 crore), peanuts compared to the $2 trillion (about Rs 165 crore) in revenue generated by the oil industry and gas every year.
There is still plenty of room in the market for high-risk, high-reward players.
The latest results show that basic science is working: the laws of physics don’t prevent us from achieving the goal of unlimited clean energy from fusion.
The problems are technical and economic. While fusion may be too far off to solve problems on the scale of a decade or two, the latest breakthrough will at least boost enthusiasm for solving one of humanity’s great challenges.
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