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. But this is a baby step; there is a lot of runway to cover before nuclear fusion takes off, experts say.

But developments elsewhere seem to challenge this view.

Headquartered in Cambridge, Massachusetts, USA, Commonwealth Fusion Systems (CFS) was set up in 2018 “on the basis of decades of MIT (Massachusetts Institute of Technology) fusion research”. It has raised $2 billion from the likes of Bill Gates, Google, Eni, Khosla Ventures, Soros Fund Management, and Temasek.

In collaboration with MIT’s Plasma Science and Fusion Center, 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.

CFS says its technology is similar to that of ITER, a multi-country collaborative research on fusion underway in France. Like ITER, CFS uses magnetic fields to confine the fusion process. However, CFS “will use a new high-temperature superconducting (HTS) magnet to enable a similar performance as ITER, but built more than 10 times smaller”, according to information provided by CFS.

Investors’ backing

CFS aims to build the demonstration plant, SPARC, by 2025 and the commercial plant by 2030.

Claims like this are usually not taken seriously, especially after the experience with the Italian engineer Andrea Rossi, who maintains that he has a device that can produce a net energy gain. Rossi made a big splash a decade ago, but nobody talks about him today.

However, CFS’s claims deserve attention because the company has the backing of investors and energy companies. Claudio Descalzi, CEO of Eni, is quoted in a January 2021 press release from CFS as saying, “Thanks to their monumental breakthroughs, a commercial fusion plant is soon going to be within reach.”

The press release also quotes Randy Glein, Partner, DFJ Growth, as saying, “The team at CFS has finally done it, breaking through longstanding technological barriers with an innovative design that promises to provide a safe, sustainable, and scalable source of clean fusion power.”

In October 2022, the United Kingdom Atomic Energy Authority (UKAEA) selected CFS to support work on the magnetic confinement system for its spherical tokamak for energy production (STEP). Describing the HTS magnets as “groundbreaking technology”, Paul Methven, Director of STEP, noted, “We believe superconducting magnets are a key part of putting fusion electricity on the grid, both economically and reliably.”

Low-energy fusion

Moving from Cambridge, Massachusetts, to Berkeley, California, you find another company that raises hopes for fusion energy.

Within nuclear fusion, there are two segments — hot and cold. While NIF, ITER and CFS work on hot fusion, where the temperature needs to be six times hotter than the core of the sun, you also have low-energy nuclear reactions, or LENR.

Brillouin Energy of Berkeley says it is building a commercial reactor that “can use the hydrogen in a glass of water to power 30,000 homes a year.” Sounds too fantastic, but the company demonstrated its ‘hydrogen hot tube’ (HHT) machine at an international conference, ICCF24, in July. Brillouin says that SRI International, a US-based not-for-profit research institute, has “independently validated the technology and heat output of the HHT boiler”.

In a press release in August, Brillouin Energy CFO David Firshein said the company “is now ready to enter into the next phase: commercialisation”.

“The HHT test system that we are demonstrating at ICCF24 is the first ever licensable system that is transportable — it can be packed up and shipped to potential OEM license partners for further testing and evaluation,” the release said.

Unexpected benefits

Perhaps fusion energy is not as far off as commonly believed.

The world is still very sceptical about LENR (for good reason, because it is still a poorly understood phenomenon), but is not ready to dismiss it either. In September, the US Advanced Research Projects Agency–Energy (ARPA-E) announced $10 million funding to “establish clear practices to determine whether LENR could be the basis for a potentially transformative carbon-free energy source”.

While some termed it a “waste of money”, others were more charitable, noting that when billions of dollars are thrown into hot fusion research, a few millions into cold fusion might be worth it.

A 2019 paper titled ‘Revisiting the cold case of cold fusion’, by a group of American scientists, noted that “the search for a reference experiment for cold fusion remains a worthy pursuit”. Also, there seem to be spin-off benefits from LENR experiments. “We set out looking for cold fusion, instead benefited contemporary research topics in unexpected ways,” the paper says.

Closer home, a team of researchers at IIT-Kanpur are working on LENR experiments, not to achieve net energy gain, but to see if transmutation can be achieved.