World’s first steam-powered piston system sparks nuclear fusion plasma in Canada

In a global first, Richmond, Canada-headquartered fusion energy company General Fusion achieved the first-ever plasma in a reactor driven by steam. This feat was achieved in the latest iteration of its prototype nuclear reactor, the Lawson Machine 26 (LM26), a press release said. 

If you were of the view that nuclear fusion is the buzzword today, then the story of General Fusion is sure to come as a surprise. General Fusion was founded in 2002 and has been working towards commercializing nuclear energy, even as its contemporaries went bust. 

While tokamaks and stellarators are technologies on which hopes of fusion energy rest currently, General Fusion has been diligently working on magnetized target fusion (MTF), a technology that emerged in the 1970s at the US Naval Research Laboratory aimed at developing compact fusion reactors. 

What is Magnetized Target Fusion? 

In 2022, the US National Ignition Facility (NIF) made global headlines after achieving the first energy gain from a nuclear fusion reaction. The key to this achievement was using lasers to compress fusion fuel, deuterium, and tritium inside the plasma to replicate reaction conditions like those in the sun. 

MTF’s approach is similar, but instead of lasers, it uses steam-driven pistons. The fuel is first magnetized using a bit of electricity, and then the pistons push a liquid lithium wall against the plasma to compress it, further increasing its temperature. At a set temperature, a fusion reaction can occur, and then the energy released will heat the liquid lithium. 

General Fusion plans to send the liquid lithium through a heat exchanger and generate steam to spin a generator. But before it does that, plasma must first be achieved. Previous attempts to do so failed since the pistons could not be controlled precisely enough. As per the firm, modern computers now allow this precise control, leading to its achievement. 

23 years to first success

General Fusion’s trust in MTF stems from the fact that the technology is designed to be practical and produce power while not requiring expensive components like superconducting magnets or high-end lasers. 

A single MTF power plant can supply power to 150,000 homes while being close to energy demand and minimizing transmission losses. The company added in a press release that the technology could help repurpose industrial steam heat and current power generation sites. 

But the journey to reach the first plasma has been a difficult one. “We’ve built 24 plasma injectors, created over 200,000 plasmas, and generated fusion neutrons from plasma compressions,” said Dr. Michel Laberge, Founder and Chief Science Officer of General Fusion, in a press release. 

With learnings from these experiments, the company designed, assembled, and operated the LM26 in a record time of 16 months. While this is a significant achievement, the company has a long way to go before delivering commercial power. 

While aiming for grid power by the next decade, the company still needs to perfect its liquid lithium wall, which is critical in its operations. Integrating the components to work in sync and produce net energy gain from the setup is an engineering challenge many are working to solve. 

If General Fusion achieves it first, it is poised to scale it rapidly.