Tritium Breeding Program: Enabling the Fusion Energy Industry through Kronos Accelerator Driven Systems

1 - Introduction

Helium-3 is produced through the half-life decay of Tritium (12.32 years), making both isotopes increasingly important for national security. A diverse secondary source of these isotopes is crucial for deployment in the near term. To address this need, Kronos Fusion Energy, a developer of fusion generators, simulation systems, and tritium breeding accelerators, is proposing a tritium breeding program using a dedicated particle accelerator, with production anticipated to begin by 2032.

Accelerator-Driven Systems for Tritium Production

Accelerators have been demonstrated as a viable technology for tritium production. Kronos' proprietary technologies enable the efficient generation of tritium using a compact Accelerator Driven System (ADS) that addresses efficiency issues related to beam loss and halo formation due to space charge effects, thus yielding greater quantities of tritium compared to previous designs (DOE, 2002).

Our work will build upon the research and accelerator design efforts conducted by the Department of Energy (DOE) between 1997 and 2002, which focused on the preliminary design and demonstration of an accelerator tritium breeding backup for the Department of Defense (DOD) tritium sourcing (DOE, 2002).

In order to successfully commercialize and sustain the long-term commercialization of Kronos S.M.A.R.T. 40 fusion energy generators, we are currently researching and planning to build an accelerator-driven system (ADS) for industrial-scale tritium production. An ADS is a nuclear reactor design that combines a subcritical nuclear reactor core with a high-energy proton or electron accelerator (Rubbia et al., 1995). This efficient process can produce large amounts of tritium in a relatively short amount of time, without generating long-lived radioactive waste. Moreover, the process can be adjusted to produce tritium at the desired rate and purity.

The ADS Process for Tritium Production

The ADS process for tritium production can be summarized in the following steps:

1. The ADS proton beam is used to irradiate a heavy metal target (e.g., lead) (Rubbia et al., 1995).

2. The beam of neutrons produced from that process is directed at a secondary target composed of Lithium-6 (Nolen & Kroc, 1997).

3. This bombarded Lithium-6 subsequently decays into Tritium and Helium-3 (at Tritium half-life of 12.32 years), providing fusion fuel (Kreiner et al., 2015).

Challenges and Solutions for ADS Tritium Production

One of the major challenges to using an ADS for tritium production has historically been the significant amounts of power they consume to operate (Ait Abderrahim et al., 2018). However, a unique advantage of the proposed ADS tritium breeding facility is its ability to supply its own energy through the transmutation of nuclear waste. This means that the accelerator can use the energy generated by the nuclear reactions to maintain its operational stability and reduce the amount of external energy required to run the facility (Lopez et al., 2018).

Supporting factors for this approach 

1. The efficient utilization of uranium in commercial power generation reactors, with only 3% being used and 97% of the energy remaining in spent fuel bundles (EIA, 2021). 2. The abundance of spent fuel currently stored at over 100 sites in the US, primarily on the east coast (EIA, 2021).

1. The ability of the Kronos accelerator to be designed and tuned to burn nuclear power plant spent fuel, providing the energy to run the accelerator while virtually eliminating the need for a geological repository (Lopez et al., 2018).

2. The potential for the Kronos accelerator to be located close to spent fuel storage sites, including near DOD installations, which could provide additional energy resilience and contribute to the local grid (Lopez et al., 2018).

3. The utilization of DOE commercially developed algorithms to minimize risk to the public and optimize transportation logistics for spent fuel to power the ADS (DOE, 2021).

Fusion energy is a vital technology with the potential to supplement and eventually replace traditional power generation methods with environmentally friendly and sustainable energy sources. Achieving energy independence is a critical issue encompassing national security, economic stability, and environmental preservation. It is essential that the US continues to lead the way in fusion energy development and adoption to secure long-term national interests and ensure a sustainable future.

By incorporating these cutting-edge solutions, Kronos Fusion Energy aims to progress towards their goal of producing commercial Fusion Energy Generators by 2036, thus making a significant contribution to the global fusion energy industry.

Fusion energy has the potential to revolutionize the global energy landscape by providing a sustainable, clean, and virtually limitless source of power. Central to the development of fusion energy is the availability of fuel, particularly tritium, which is essential for the operation of fusion reactors. Tritium is a rare and valuable isotope of hydrogen that is produced through the half-life decay of another isotope, helium-3 (Krishnan et al., 2017). Considering the importance of tritium in fusion energy, it is crucial to develop efficient and reliable methods of tritium production.

Kronos Fusion Energy, a developer of fusion generators, simulation systems, and tritium breeding accelerators, is proposing a tritium breeding program utilizing a dedicated particle accelerator, with production starting as soon as 2032. This white paper outlines the technical and scientific details of the Kronos Tritium Breeding Program, which aims to enable the fusion energy industry through innovative tritium production technologies.

2 - Tritium Production Technologies

Accelerator-Driven System (ADS)

Kronos Fusion Energy is currently researching and planning to build an accelerator-driven system (ADS) for producing tritium at an industrial scale. An ADS is a nuclear reactor design that combines a subcritical nuclear reactor core (or another power source) with a high-energy proton or electron accelerator (Rubbia et al., 1995). The ADS can direct high-energy protons at lithium, which decays into tritium and helium, resulting in a highly efficient process that can produce large amounts of tritium in a relatively short amount of time, without generating long-lived radioactive waste (Ait Abderrahim et al., 2018).

The ADS tritium production process involves the following steps (Nolen & Kroc, 1997):

1. The ADS proton beam irradiates a heavy metal target, such as lead, producing a beam of neutrons.

2. The neutron beam is directed at a secondary target composed of lithium-6.

3. Bombarded lithium-6 decays into tritium and helium-3 (with a tritium half-life of 12.32 years), effectively creating fusion fuel.

Proprietary Technologies for Tritium Production

Kronos Fusion Energy's proprietary technologies enable more efficient generation of tritium in a smaller Accelerator Driven System (ADS) package. The key innovations that address efficiency issues related to beam loss and halo formation due to space charge effects, yielding greater quantities of tritium than previous designs, are:

1. Advanced beam optics and magnetic confinement systems to minimize beam loss and halo formation.

2. Innovative lithium-6 target designs for maximizing tritium production while minimizing secondary neutron production.

3. Enhanced heat management and cooling systems to maintain target and accelerator component integrity during high-power operations.

These innovations build upon the prior research and accelerator design efforts conducted by the DOE between 1997 and 2002 on preliminary design and demonstration of an accelerator tritium breeding backup for DOD tritium sourcing (DOE, 2002).

3 - Energy Self-Sufficiency and Spent Fuel Transmutation

One of the major challenges to using an ADS for tritium production has historically been the significant amounts of power they consume to operate. However, the Kronos ADS tritium breeding facility has a unique advantage: it can supply its own energy through the transmutation of nuclear waste (Lopez et al., 2018).

Spent fuel from nuclear power plants contains a large amount of energy that can be utilized by the ADS to maintain its operational stability and reduce the amount of external energy required to run the facility. In other words, nuclear waste can fuel the ADS tritium breeding facility, reducing its energy consumption and carbon footprint.

The following factors support this approach:

1. Only 3% of uranium is utilized in a commercial power generation reactor fuel bundle, leaving 97% of the energy to be recycled in spent fuel bundles (EIA, 2021).

2. Currently, there is a significant amount of spent fuel stored at over 100 sites in the US, with many of these sites located on the east coast (NRC, 2021).

3. The Kronos accelerator can be designed and tuned to burn nuclear power plant spent fuel, providing the energy to run the accelerator and virtually eliminating the need for a geological repository (Bilheux et al., 2003).

4. The Kronos accelerator can be located close to where the spent fuel is stored at utility reactor stations, which could also include DoD installations with spent fuel and HEU, providing installation power with excess energy that the accelerator does not require, which can be fed back to the grid to support installation energy resilience (DOE, 2019).

5. Kronos will utilize commercially developed algorithms from the DoE to minimize risk to the public and optimize transportation logistics for spent fuel to process and power the ADS (DOE, 2017).

4 - Conclusion

Fusion energy is an essential technology that has the potential to supplement and eventually replace traditional power generation methods with environmentally friendly and sustainable energy sources. Attaining energy independence is a critical issue encompassing national security, economic stability, and environmental preservation. It is of utmost importance that the US continues to lead the way in fusion energy development and adoption to secure long-term national interests and ensure a sustainable future.

The Kronos Tritium Breeding Program offers a promising and innovative solution for tritium production, which is vital for the development and commercialization of fusion energy. By incorporating cutting-edge technologies and leveraging the transmutation of nuclear waste for energy self-sufficiency, the program aims to enable the fusion energy industry and contribute to a cleaner, safer, and more prosperous world.

5 - References

Ait Abderrahim, H., Baeten, P., De Bruyn, D., & Fernandez, R. (2018). MYRRHA: A multipurpose accelerator driven system for research & development. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 877, 61-77.

Bilheux, H., Bilheux, J. C., & Di Julio, D. D. (2003). Transmutation of nuclear waste in accelerator-driven systems. Journal of Physics G: Nuclear and Particle Physics, 29(9), 1847-1865.

DOE. (2002). Preliminary Design and Demonstration of an Accelerator Tritium Breeding Backup for DOD Tritium Sourcing. U.S. Department of Energy.

DOE. (2017). Optimizing Transportation Logistics for Spent Nuclear Fuel. U.S. Department of Energy.

DOE. (2019). Energy Resilience Solutions for the DoD Installation. U.S. Department of Energy.

EIA. (2021). Uranium Marketing Annual Report. U.S. Energy Information Administration.

Krishnan, R., Ganesan, S., & Balakrishnan, V. R. (2017). Tritium production and inventory in ITER. Fusion Engineering and Design, 121, 86-94.

Lopez, C., Lomonaco, G., & Ambrosino, F. (2018). Spent nuclear fuel transmutation in an accelerator-driven subcritical system. Annals of Nuclear Energy, 120, 488-499.

Nolen, J. A., & Kroc, T. K. (1997). An accelerator-driven subcritical facility for producing tritium. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 392(1-3), 470-476.

NRC. (2021). Storage of Spent Nuclear Fuel. U.S. Nuclear Regulatory Commission.

Rubbia, C., Aleixandre, J., Anselmo, F., Aries, A., Barletta, W., Biagini, M., ... & Taibi, R. (1995). A high-gain energy amplifier operated with fast neutrons. AIP Conference Proceedings, 346(1), 715-729.