Per Peterson talks about Kairos Power at ANS Winter 2018

In some ways, Kairos Power has a familiar sounding story. It is a California-based start-up founded by three bright people, all with a tie to Cal Berkeley (UCB). They have decided to turn their grant-funded tech research into a for-profit company. One of the founders, Dr. Per Peterson, is a long established UCB professor with a national reputation, two had been his students during their doctoral research.

Dr. Ed Blandford earned his PhD at UCB about a decade ago and had established his reputation as an expert in thermal hydraulics through five years of experience as a project manager at EPRI and leading a research program at the University of New Mexico as a tenure track professor.

Dr. Mike Laufer, the third founder, came to Berkeley after earning a degree at Stanford. That’s a place that is known for being deeply infected with entrepreneurial fever. A Google search on Mike’s name might make one believe he has had a long, successful career in medicine and medical device development, but that’s a Mike from a previous generation.

During a plenary presentation on the first day of the 2018 ANS Winter Meeting, Per Peterson, Kairos’s Chief Nuclear Officer, described Kairos CEO Mike Laufer’s policy of starting every meeting with a review of the company’s mission statement.

Kairos Power has a mission to enable world’s transition to clean energy, with the ultimate goal to dramatically improve people’s quality of life while protecting environment.

The unique kicker to this story is that the tech that has inspired these particular academics isn’t software, network, communications or computer focused. Instead, it’s a nuclear energy tech with unique features and material science-related innovations.

What is Kairos Power?

Many readers may have never heard of Kairos Power. They’re a relatively new entrant in the rapidly expanding field of advanced nuclear technology. The three company founders published an article in Foreign Affairs in the spring of 2014 that described the direction they thought nuclear energy development needed to take to achieve success. That article did not mention Kairos, probably because it was still in the planning phase. It’s evident that Kairos founders were thinking hard about what they would do differently.

Since founding the company, they’ve been primarily focused on building a solid foundation and have not put much effort into public communications. Like almost every company in existence, Kairos has a web site, but as of Nov 13, 2018, the “Technology” page includes a fair amount of obsolete information about their design choices. (By the time you read this Kairos may have found enough time to create some new material for the web site.)

Kairos was formed to commercialize the Fluoride High-temperature Reactor (FHR) concept that UCB has been working on in cooperation with MIT and the University of Wisconsin (Madison) since 2011.

What is an FHR?

The FHR is a system that uses Triso-coated particle fuel in a pebble bed configuration, and uses a fluoride-beryllium molten salt to move fission-generated heat out of the pebble bed reactor.

The FHR idea is to combine some of the best features of reactors typically cooled by a gas like helium or nitrogen with some of the best features of molten salt fluid fueled reactors. According to Kairos technologists (specifically Per Peterson and Ed Blandford) the combination also avoids some of the limitations of Individual parent technologies.

Molten salt has a much higher heat capacity than gas. Its features enables slower coolant velocities, a much smaller pressure drop across the reactor, smaller pumps and valves and substantially smaller diameter pipes. It also remains at atmospheric pressure.

During a presentation in the thermal hydraulics topical meeting occurring in conjunction with the ANS Winter meeting, Ed Blandford, Chief Technical Officer of Kairos, mentioned that Kairos pebbles are smaller than the typical 6 cm pebbles chosen for most pebble-bed conceptual reactors. Smaller pebbles have the advantage of higher surface to volume ratios for enhanced heat transfer. He indicates this logical choice wouldn’t be as easy for gas cooled reactors.

When I asked him why gas-cooled designs would be challenged with smaller pebbles, he described how the slower coolant flow through the core reduces the pressure drop penalty that gas cooled reactors would pay if they used smaller pebbles. That pressure drop penalty is a result of the narrower coolant paths introduced with smaller pebbles.

Compared to reactors that use fuel that is dissolved in molten salts, the FHR concept avoids moving fission products throughout the primary system. Its pumps and valves will be accessible so they can be repaired or replaced if necessary.

Wasn’t Kairos planning to burn natural gas to boost power output?

People who have heard of Kairos might recall that the design concept taken from the university setting included input from natural gas.

Soon after the point where the design and innovation development work was converted into a profit-focused corporate product effort, Kairos leaders made an important, risk-reducing decision.

The company chose to shelve the idea of designing and building a flexible, optimized facility using an open cycle air compressor-turbine heat conversion system with a natural gas fired supplementary heater used during high demand periods.

Instead, the team decided to follow Rickover’s advice of introducing one major innovation at a time. That design model allows the innovation to be fully tested using a mostly proven supporting system.

Kairos’s current design concept includes a secondary heat transfer loop that uses “solar salt” to move heat from the FLIBE in the primary loop into a steam generator that can deliver steam at modern commercial steam plant conditions.

Development roadmap and timeline

Ed and Per were careful to point out that their choices still left some significant challenges to address. There are good reasons why they are targeting prototypical operation sometime before 2030 with readiness for rapidly increasing commercial deployment in the early 2030s.

We talked about the important issues of heat exchangers, pumps, valves, and control system design, manufacture and testing, provisions for ensuring the molten salt coolant doesn’t freeze, and the always important challenge of identifying unexpected material incompatibilities somewhere in the broad range of operating and transitional temperatures.

One challenge that we talked about for several minutes was the steam generator. The most fully developed similar components in use today are part of solar thermal power stations. Those solar salt to steam heat exchangers are pretty close to the devices that Kairos needs, but their temperatures are pressures are not as high.

Like the usual tech more commonly associated with the San Francisco Bay Area and Silicon Valley, Kairos’s tech includes never-before attempted features that demand rapid feedback testing. New ideas like those coming from Kairos developers cannot be incorporated without experimental evidence that they will work as expected.

As Per explained to me, he and his team have created a facility and a system of testing that ensures potential obstacles are identified and overcome as early as possible in the design process. They are excited about their facilities – which include a uniquely historical and appropriate view – and about coming to work every day to address exciting advances along with challenging problems.

Kairos is hiring. They have 62 full time equivalent positions filled, but there are a number of additional opportunities available. Kairos is looking for people with the necessary skills.

I believe they need to search widely for people with a hunger to participate in a potentially world changing technology development effort. New hires will be facing a lengthy period of chellanges that must be overcome before commercial production.

Disclosure: This article was substantially enhanced by a face to face conversation over lunch with Per Peterson and Ed Blandford. There is every possibility that it was favorably influenced by the fact that Per picked up the tab for my burger, fries and unsweetened ice tea. I know that accepting such generosity might be considered a violation of journalistic ethics. But then, I’m just a poor blogger without much of an expense account.

Note: When Per Peterson first told me about Kairos’s recent move to a new headquarters and lab building in Alameda, CA, I couldn’t help asking him, “Is that where the nuclear wessels are kept?”

The joke may be lost on those who have not seen all of the Star Trek movies, but it relates to a classic scene where Chekov and Ohura are wandering the streets of 20th century San Francisco wearing their uniforms. They approach a uniformed motorcycle cop and ask for directions to Alameda, where the nuclear “wessels” are kept.