Pacific Fusion’s Innovative Approach to Cost-Effective Fusion Energy
The quest for practical fusion energy has long been hindered by the challenge of initiating reactions at a cost lower than the market price of the generated power. While numerous strategies have been proposed, a definitive solution remains elusive. For instance, Commonwealth Fusion Systems is investing several hundred million dollars into constructing a large-scale reactor, slated for activation next year, leaving the economic viability question unanswered for now.
Emerging companies, such as Pacific Fusion, are exploring more economical pathways to fusion energy. Recently, Pacific Fusion disclosed the outcomes of a series of experiments conducted at Sandia National Laboratories, revealing potential cost-saving modifications to their fusion approach.
Fusion energy offers the promise of continuous, large-scale electricity generation, aligning seamlessly with existing grid infrastructures. Many fusion startups aim to launch their first commercial power plants between the early and mid-2030s.
Pacific Fusion is focusing on a method known as pulser-driven inertial confinement fusion (ICF). This technique involves rapidly compressing small fuel pellets, leading to atomic fusion and energy release. Unlike the National Ignition Facility (NIF), which employs lasers for compression, Pacific Fusion utilizes powerful electrical pulses to generate a magnetic field that swiftly compresses the fuel pellet, approximately the size of a pencil eraser, in under 100 billionths of a second.
The faster you can implode it, the hotter it’ll get, explained Keith LeChien, co-founder and CTO of Pacific Fusion.
A significant hurdle in pulser-driven ICF has been the necessity of preheating the fuel pellet to achieve the requisite fusion temperatures. Traditionally, this has involved additional lasers and magnets, introducing complexity, cost, and maintenance challenges.
In their experiments at Sandia, Pacific Fusion refined the design of the cylinder encasing the fuel pellet and adjusted the electrical current delivery. By allowing a portion of the magnetic field to permeate the fuel before compression, they achieved the necessary preheating without auxiliary systems.
We can make very subtle changes to how this cylinder is manufactured that allow the magnetic field to leak or to seep into the fuel before it’s compressed, LeChien noted.
The fuel is housed in a plastic target wrapped in aluminum. By varying the aluminum’s thickness, Pacific Fusion can control the magnetic field’s penetration into the fuel. This manufacturing process requires precision comparable to that of producing a .22 caliber bullet casing, a well-established industry standard.
The energy required for this magnetic field adjustment is minimal, constituting less than 1% of the system’s overall energy, making it virtually negligible.
Eliminating the need for additional magnetic systems simplifies the reactor’s design and maintenance, leading to modest cost reductions. However, removing the laser preheating system offers substantial savings, as such systems can cost upwards of $100 million.
LeChien emphasized the importance of aligning simulations with real-world experiments: A lot of people have simulated things and said, ‘Oh, this will work or that will work.’ It’s a very different game to simulate something, build it, test it, and have it work. Closing that loop is hard.
