Imagine a source of energy that can help conserve natural resources and doesn’t create hazardous byproducts. Imagine a source that’s widely accessible to reduce natural resource conflicts across the globe and provides affordable, 24/7 on-demand electricity.
That’s what nuclear fusion energy could do. Scientists and physicists have been researching and attempting to understand and create it since the early part of the 20th century. As soon as it becomes practicable, it will have a worldwide impact on the way energy is produced.
TAE Technologies, an advanced clean fusion energy technology company, is working on making this vision a reality. It's doing so by taking an alternative approach of generating fusion power via field-reversed configuration (FRC).
Producing fusion power involves confining plasma with magnetic fields in a toroidal chamber, which is the shape of a doughnut, to create nuclear fusion reactions that produce heat for electricity generation. FRC does it differently. The chamber is tube-shaped, allowing for easier construction, and it creates a high current to produce many plasma toroids (think: mini doughnuts) that combine into one self-confined toroid to generate heat.
The machine TAE Technologies constructed, called “Norman”in honor of physicist and late company co-founder Norman Rostoker, does just that. The ability to harness fusion energy depends on achieving the Hot Enough, Long Enough (HE/LE) milestone, which means the longer superheated plasma is kept in a stable state, the closer the machine is to creating clean, perpetual energy. TAE Technologies’ previous version of the machine checked off the “Long Enough” box, and now, Norman is planned to check off “Hot Enough.”
Norman is a linear device with enhanced magnetic, heating and vacuum systems. It is expected to create plasma reaching nearly 35.5 million degrees Fahrenheit, which is hotter than the sun’s core. But achieving this milestone will be no walk in the park.
Not your average vacuum
As a privately funded company, TAE Technologies is careful about how they allocate every dollar. In fact, all funding was earned by applying a practical “money by milestone” business model, supported by more than $600 million of equity capital from some of the world’s leading investors. One way the company ensures success of a new process or machine before spending millions on engineering and building it is through small scale simulation.
“We apply sound engineering principles to help us find results and solutions to a problem,” said Andy Sibley, chief engineer, controls and electrical, TAE Technologies. “We start with what we know and have dealt with in the past and then very quickly hone in on an idea or concept to address the issue. Then, we simulate and test the idea – or in some cases, we inherently know how to engineer the solution.”
To create Norman, TAE Technologies started by making design modifications to it's previous machine. One area of focus was the need for a high quality vacuum for the 110-foot portion, which consists of seven chambers interlocked by gate valves. The gate valves are like doors on a submarine ship; when they’re open, it creates one large vacuum vessel.
An operator can open and close the valves and monitor gauges based on defined limits, but there also needs to be a control system engineered with certain parameters to prevent an operator from making changes that could potentially harm the machine.
For example, an operator cannot open a valve if there’s high pressure on one side of the vessel and low pressure on the other side. These parameters are in place to limit potential damage to the high speed turbo pumps. A mistake could cost hundreds of thousands of dollars. However, operators also need certain functionalities in place to override limits that they can validate elsewhere within the control system.
While designing upgrades to the vacuum, the TAE Technologies team determined simulation wasn’t necessary, although it did need an understanding of the system limits to know what’s possible. So, it chose a solution it was familiar with – one that had a proven, reliable track record – and turned to their partners at Rockwell Automation.
Connecting the dots
The machine’s vacuum has a complex relationship with each valve, vault, pump, interlock and switch connected to it. When there’s activity in the vacuum, the system carries out a checklist of tasks in sequence – much like launching a space rocket. There’s prep work, a countdown, a take-off and a landing.
TAE Technologies needed a system that would control virtually every component that was part of the equation. “We needed to break the vacuum system down into smaller functions to help us understand and set controls for every connection point, especially because the vacuum’s system feeds into a much larger, complex system,” Sibley said.
As part of the solution, TAE Technologies used the Allen-Bradley ControlLogix controllers from its previous machine and worked with Rockwell Automation to reengineer the solution for Norman. This helped reduce design and engineering time. Together, they built simple, flexible controls, and worked with programmers to build rules and limits for each component. They used add-on instructions (AOIs) as standard building blocks for control functionality.
Rockwell Software FactoryTalk View Site Edition (SE) software was also implemented to give operators a detailed look into each of the seven vacuum chambers. There are minor differences for every component of the vacuum, and the software allows operators to quickly view trending data on pressure levels or pump speed, for example.
“We knew we had a reliable system with Rockwell Automation because we’ve used the solution before,” Sibley said. “And this upgrade gave us a system that monitors our controlled, autonomous fault routines. It’s a system we can rely on any time there’s activity in the vacuum.”
Hot and getting hotter
Machine downtime for TAE Technologies can cost as much as $100,000 per day, but the financial impact of downtime isn’t the only concern – it also puts a pause on the science. “We can’t put a dollar amount behind the loss of science, and this system helps ensure that won’t be an issue – it just works,” Sibley said.
The vacuum is one of 50 systems that needs to work seamlessly for the machine to function properly, which means operators need trusted, reliable control. With the solution from Rockwell Automation, TAE Technologies has peace of mind that the vacuum will work, allowing them to focus their energy on what matters most: delivering on the promise of fusion.
To achieve their goal of creating clean fusion energy, TAE Technologies will eventually need to build a machine that can create plasma that reaches 5.4 billion degrees Fahrenheit. “It’s a long road ahead, but Norman brings us one prominent step closer,” Sibley said.