March 5, 2016 – Back in 2013 I wrote a brief note about General Fusion in a posting on Canadian nuclear technology development. At the time the technology was about 15 years away from completion of a commercial fusion reactor.
Yesterday Sustainable Development Technology Canada (SDTC) awarded the company $12.75 million to take its design to a full-scale fusion energy demonstration system similar to the one pictured at the bottom of this posting. In the announcement General Fusion indicated in addition to the SDTC money it has been able to raise more than $100 million from a wide range of global investors .
What is magnetized target fusion technology (MTF)?
On the company’s website it describes a sphere filled with pumped molten lead-lithium. The pumps spin to form a vortex with a hollowed centre. Magnetized plasma composed of deuterium-tritium fuel gets inserted into the hollow. An array of 300 pistons surrounding the sphere apply pulsed pressure to create high pressure compression of the plasma. The pressure increases in strength to create a shock wave collapsing the cavity and resulting in a fusion burst of fast neutrons. Those escaping neutrons heat the liquid metal which in turn transfers that heat to an exterior vessel containing water. The water then gets converted to steam to drive a turbine attached to a generator. The system is closed, that is, once it’s kick started it remains self-contained continuously recycling with no nuclear waste.
MTF technology was first proposed in the 1970s as a low-cost nuclear fusion reactor option. Unlike a tokamak the design and scale are quite simple. Some pioneering work was conducted by the U.S. Naval Research Laboratory. These early experiments ran into problems such as achieving sufficient vortex velocity and designing appropriate compression technology so that the plasma could yield a fusion reaction.
General Fusion has been working on overcoming these design issues. It has developed timed acoustic compression using advanced servo controllers. The company is also working on perfecting plasma injectors so that they can be used to fire the deuterium-tritium fuel into the hollowed centre of the vortex with precision.
In the picture below you can see a 2011 prototype of the containment vessel surrounded by installed piston housings. And although there is still no fixed date in the near future when General Fusion will have its operational prototype working, the latest investment dollars should help the company achieve a technically viable fusion reactor at a cost far below that of ITER, the multi-billion dollar tokamak fusion reactor project being built in the south of France.