While the electric vehicle (EV) market faces an uncertain future, there’s no uncertainty about the fact that greenhouse gas emissions are drastically changing the climate on Earth. Thanks to its ability to create previously impossible, more energy efficient designs, additive manufacturing (AM) is a key tool for slowing, or even halting, the rate of global warming. For this reason, there is an enormous opportunity for governments and companies to deploy 3D printing for new energy solutions.

Among the firms leading the charge is Hyliion (NYSE: HYLN), which, in the course of a critical industry pivot, has adopted AM to produce a novel energy solution: the KARNO generator. Fuel agnostic, the KARNO generator features metal 3D printed parts to achieve improved efficiency when generating power. In an exclusive interview with Hyliion CEO and founder Thomas Healy, a new vision of electrification emerges, merging past innovations with future technologies to redefine the power landscape.

Streamlining Electricity

Hyliion’s 200-kilowatt KARNO generator harnesses the power of flameless oxidation, a process where a meticulously controlled mix of fuel and air reacts to create a highly efficient and ultra-clean combustion. This reaction generates heat, which is then directed to the coil areas of the linear generator. Inside, a gas is heated and expands within the cylinder, driving the generator’s piston forward. In an elegant symphony of motion, while the piston moves in one direction, a corresponding action occurs in reverse, resulting in a harmonious oscillation.

The generator’s heartbeat is an electric motor, which capitalizes on the kinetic dance of the pistons. Through the interplay of magnets and coils, this reciprocating movement is transformed into electrical energy. The Stirling engine, the conceptual predecessor to this generator, has been known for more than a hundred years. However, its widespread application has been hindered by inefficiencies in heat transfer, a crucial aspect for its operation across diverse scenarios. Tackling this challenge head-on, Hyliion leverages 3D printing to create complex heat exchanger components within the generator’s shafts. It’s this pivotal innovation in component design that enables the generator to reach the elevated levels of efficiency essential for its optimal performance.

“The type of generator that we’re making is a linear heat generator based on the Stirling Engine design, which haven’t been used widely because it hasn’t been possible to get the necessary  efficiency out of one. However, additive  [manufacturing] allows us to design and print components that could never have been made before,” Healy said. “That’s what makes this KARNO generator feasible.”

Hyliion’s Shift: From Roads to the Grid

Founded in 2015, Hyliion initially set out to electrify commercial transportation, transforming semi-trucks into hybrid electric vehicles with on-board generators. This path led them to a pivotal public offering in 2020, and shortly after, a partnership with GE, presenting a unique generator technology to bolster their electric vehicles. Healy’s team was captivated by GE’s KARNO generator and eventually acquired the technology, infusing Hyliion with new potential.

“GE actually approached us to ask if we’d like to use its generator technology as the power plant onboard trucks in order to charge the batteries. It fit perfectly into to our roadmap, so we started working with GE,” Healy said. “Because we really liked where the KARNO generator was heading, we actually bought the technology from the company.”

However, the electric vehicle sector is facing tumultuous times. As companies navigate through financial storms, many are reevaluating their commitment to electric technologies. Amidst this uncertainty, Hyliion opted for a strategic pivot — from focusing on electric powertrains to harnessing the KARNO generator for stationary power generation.

“We took a hard look. We noted that we’ve got an ample amount of capital and two really interesting technologies under one roof,” Healy said. “The vehicle side was becoming really challenging. So, in the last six months, we decided to wind down powertrain operations and focus the team on KARNO technology in stationary applications.”

GE’s Skunkworks to Hyliion’s Vision

As Healy described it, the KARNO development team was essentially GE’s equivalent of a Skunkworks program. Thus, the integration of the group into Hyliion was smooth, given the team’s startup-like dynamism within the larger structure of GE. The transition bolstered Hyliion’s workforce with about 15 to 20 percent of the original GE team, all of whom remained, signaling a successful acquisition.

“That integration has gone really well. Then, we’ve expanded to include more team members in Ohio, where the KARNO development team was originally based. We’ve also taken people who are part of the powertrain focus and moved them to focus on stationary power generation because, at the end of the day, it’s a different technology but it has a lot of overlap: how do you move electricity from batteries to an e-motor on a truck as opposed to how do you move electricity from a generator into the grid.”

Hyliion operates from two primary locations: Cincinnati, Ohio, for research and development and Austin, Texas, for manufacturing. The production journey began with single-digit unit output, and after various iterations, has now reached what Hyliion considers its production-intent or BETA design. The company anticipates low volume production in the near term, with revenue growth expected to reach the low double-digit millions in the following year.

“Long term, we do see scaling into much more sizable numbers, which is going to need more additive machines and increasing their throughput. The nice thing is that we’ve run the economics already, and based on where additive technology is today, we can make this an economically viable product. What’s will be interesting isas we go forward and increase speed and throughput, it will determine how much more of the market can we go after—like competing directly against a conventional diesel engine. The nice thing is that the KARNO generator has a much lower operating cost than conventional generators do. So, you don’t necessarily need to get cheaper upfront than a diesel,ou just need to be less expensive over the long-term total cost of ownership.”

Given Hyliion’s history with GE, it’s no secret that the company uses Concept Laser powder bed fusion machines to 3D print its parts. This began with the entry-level M Lab system, before the company advanced to M2s and then an X-line, the largest printer in the series. Despite the fact that Hyliion has progressed to the highest end of GE 3D printers, the company continues to use the M Labs alongside it in order to fill capacity.

Generation Applications

The KARNO generator stands at the forefront of efficiency and versatility. Designed for distributed power generation, it promises to make a profound impact on power needs, boasting fuel-agnostic capabilities and higher efficiency compared to traditional grid operations.

Hyliion has outlined four primary markets for the KARNO generator: EV charging, waste gas from landfills and oil and gas sites, prime power for commercial buildings and data centers, and mobility. The company already has customers set up in some of those buckets. Once BETA units are shipped out to them later this year, the plan is to scale growth heading into next year.

“We need more power generation for the grid. We have things like data centers, EV chargers, and more things being electrified, more generally. We need more power. One of our philosophies is that the best way to get more power is to move to more efficient power generation. If you look at the grid today, it operates at like 35% efficiency. If we can make the grid 50% efficient, you just solved the need for more power without having to use more fuel to make that power. That’s where the KARNO generator is: that step change.”

Rather than clear out 250 acres of land to set up a power plant, KARNO technology makes it possible for an existing facility to improve its energy efficiency nearly instantaneously. Healy emphasizes the generator’s ability to transition seamlessly between over 20 fuels, including hydrogen and natural gas, with small adjustments to software but no hardware modifications.

“This solves the problem of what the grid is facing, where people don’t know what the fuel of the future is. There’s so much speculation around hydrogen, but now ammonia is coming into the discussion. There are some people who say that we’re going be running natural gas for a long time and it’s not going away anytime soon. The KARNO generator gives you that flexibility that’s kind of future-proof. It also offers a more immediate deployment capability. Whereas a power plant is going take many years to build, the KARNO generator could be deployed behind your facility and start making power immediately.”

Going forward, AM not only presents a huge opportunity for Hyliion, but energy generation presents a huge opportunity for 3D printing as well. As efficiency gains are achieved beyond the field of aerospace and in energy overall, there’s a chance for countless industrial and consumer systems to be improved with AM. As a result, GHG associated with human activity can be reduced while also giving 3D printing the momentum it needs to scale. This is an area of which Hyliion is keenly aware, meaning that, as the world embarks on an unprecedented shift to new forms of fuel, the company could stand to be one of the major drivers and benefactors in the process.

Images courtesy of Hyliion.