In China, Wuling launches electric minivan, Chevrolet introduces 48V MHEV Monza
ACEA: plug-in vehicles take 6.8% market share in Europe in Q1 2020; HEVs at 9.4%

ORNL team developing 3D-printed nuclear reactor core; Transformational Challenge Reactor (TCR)

Researchers at the Department of Energy’s Oak Ridge National Laboratory are refining their design of a 3D-printed nuclear reactor core, scaling up the additive manufacturing process necessary to build it, and developing methods to confirm the consistency and reliability of its printed components.

The Transformational Challenge Reactor Demonstration Program’s approach to nuclear energy leverages advances from ORNL in manufacturing, materials, nuclear science, nuclear engineering, high-performance computing, data analytics and related fields.


ORNL scientists have selected and optimized a design for printing over a three-month period, demonstrating the ability to rapidly produce a prototype reactor core. Credit: Brittany Cramer/Oak Ridge National Laboratory, US Dept. of Energy

The lab aims to turn on the first-of-its-kind reactor by 2023. The program has maintained its aggressive timeline during the COVID-19 pandemic, using remote work to continue design and analysis efforts.

The nuclear industry is still constrained in thinking about the way we design, build and deploy nuclear energy technology. DOE launched this program to seek a new approach to rapidly and economically develop transformational energy solutions that deliver reliable, clean energy.

—ORNL Director Thomas Zacharia

Reactor development and deployment have traditionally relied on materials, fuels and technology pioneered in the 1950s and ’60s, and high costs and decades-long construction times have limited the United States to building only one new nuclear power plant in the last 20 years.

TCR will introduce new, advanced materials and use integrated sensors and controls, providing a highly optimized, efficient system that reduces cost, relying on scientific advances with potential to shape a new path in reactor design, manufacturing, licensing and operation.

The TCR program has completed several foundational experiments including selection of a core design, and a three-month “sprint” that demonstrated the agility of the additive manufacturing technology to produce a prototype reactor core quickly.

Researchers will now focus on refining the selected design and the processes that will ensure an optimal and reliable energy system. Monitoring technologies continually assess the manufacturing process, providing live data streams that enable real-time qualification of the printed material and performance analysis through artificial intelligence. The team also conducts extensive post-build testing to assess component performance and establish links between the behavior of each unique part and its live manufacturing data.

We have been aggressively developing the capability to make this program a reality over the last several months, and our effort has proven that this technology is ready to demonstrate a 3D-printed nuclear reactor core The current situation for nuclear is dire. This is a foundational effort that can open the floodgates to rapid innovation for the nuclear community.

—Kurt Terrani, the TCR technical director

As part of deploying a 3D-printed nuclear reactor, the program will also create a digital platform that will help in handing off the technology to industry for rapid adoption of additively manufactured nuclear energy technology.

The entire TCR concept is made possible because of the significant advances in additive manufacturing process technology. By using 3D printing, we can use technology and materials that the nuclear community has been unable to capitalize on in the last several decades. This includes sensors for near autonomous control and a library of data and a new and accelerated approach to qualification that will benefit the entire nuclear community.

—Kurt Terrani

Although nuclear power plants provide nearly 20% of U.S. electricity, more than half of US reactors will be retired within 20 years, based on current license expiration dates.

The TCR program will provide a new model for accelerated deployment of advanced nuclear energy systems. If cost and construction times are not addressed in the very near future, the United States will eventually lose its single largest source of emissions-free power.

—Thomas Zacharia

ORNL is partnering with Argonne and Idaho national laboratories and engaging with industry to enable rapid adoption for commercial use.

The hexagonal structure took close to 40 hours to build, with temperatures reaching over 1,400 degrees Celsius around the melt pool where a laser heats and melts while adding a new layer. Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy

The Transformational Challenge Reactor builds on ORNL’s 77-year history of international leadership in nuclear science and technology development. The lab began as home to the world’s first continuously operating reactor, and its scientists and engineers pioneered technology and expertise in the first decades of the Atomic Age.

Today, the lab operates the High Flux Isotope Reactor, a DOE Office of Science user facility that provides a world-leading source of neutrons for a variety of research and produces isotopes for medicine, industry, and space exploration. TCR will be the 14th reactor built and operated by ORNL.

TCR is supported by DOE’s Office of Nuclear Energy.



3d printing a reactor.
That is so hardcore!


Thomas Pedersen

Imagine just 40 hours manufacturing time for that part...

And then add on built-in material integrity qualification and it's a game-changer


First of all, we know ORNL knows Additive Manufacturing, remember the classic 3d printed Shelby Cobra they built.
My questions relate to what is the plan for the TCR beyond this test reactor. We know that this is a very small 3 GW thermal reactor uses Yttrium Hydride as the moderator (NASA used this during the 1960s for very light space based designs) - Mars mission maybe?
It is a high temperature helium gas cooled reactor, so very efficient - could it be like the General Atomic Energy Multiplier Module (EM2) which is designed to operate 30 years and can use Spent Nuclear Fuel (SNF). I believe ORNL is working with Idaho National Laboratory on SNF for this project.
Any thoughts?

Darryl Siemer

In my opinion, projects like this are a waste of time, my tax dollars, and ORNL’s talents. Addressing the energy-related problems that the world will be facing circa 2100 AD with nuclear power will require 20-30 TWe’s worth of sustainable (breeder) reactors more or less close-coupled to efficient reprocessing systems more or less close-coupled to efficient waste treatment systems, not tiny toy (3 MWt?) reactor concepts like this regardless of how “advanced” or “efficient “ it might be or how cleverly its core might be made (printed?). Weinberg would be disheartened by this sort of nonsense.
If anyone wants to discuss this further give me a call at 208 521 5418 or send a note to


Obviously, Dr. Siemer knows that ORNL is also working on the Molten Chloride Fast Reactor (MCFR) technology with TerraPower, INL, and Southern Company (where I worked in the 70's during the heyday of Nuclear Power development, Alvin Vogtle was the Chairman and Plant Vogtle started construction when I was there). The MCFR follows on the great pioneering MSR work that Alvin Weinberg oversaw and one that I hope succeeds. The MCFR is a traditional size reactor, after testing, Southern Company and TerraPower plan to develop a 1,100-megawatt prototype reactor by 2030.
Can we beat that timeline - Plant Vogtle Units 1 and 2 took over 10 years to complete, Units 3 and 4 not much better? Will DOE make Small Modular Reactors easy to license? Can Additive Manufacturing make Reactor technology cheaper?
An 80 MW electric (150 MW thermal) power plant that fits on a truck, that lasts 30 years, uses SNF, buried underground, and costs less than $3000/kW seems like a good idea. We need them both.


Fast reactors can use some of the 700,000 tons of depleted uranium waste from enrichment for fuel. The amount of long term radioactive waste is greatly reduced.

Aydan Maldonado

First of all, we know ORNL knows Additive Manufacturing, remember the classic 3d printed Shelby Cobra they built.

The comments to this entry are closed.