Nuclear Energy with NTU Alum Dr Theodore Ong
In an interview, NTU Engineering alum Dr Theodore Ong discusses his interest and career in nuclear engineering. Now a research fellow at the Singapore Nuclear Research and Safety Initiative (SNRSI), he develops simulations for molten salt natural circulation systems while mentoring future nuclear researchers.
Dr Theodore Ong earned his Bachelor of Engineering in Chemical and Biomolecular Engineering from NTU in 2018. After gaining research exposure through both NTU’s Undergraduate Research Experience on Campus (URECA) and Singapore’s Agency for Science, Technology and Research (A*STAR), Ong enrolled and completed his PhD in Nuclear Engineering at the University of California, Berkeley.
What sparked your interest in nuclear engineering and research?
As a child, I read illustrated encyclopaedias on nuclear reactors, but games like Command & Conquer: Red Alert 2 and Cold War-era films like The Hunt for Red October deepened my fascination with nuclear technology. It was always presented as the ultimate power source or superweapon, and that made me curious about the science behind it.
While the Fukushima disaster initially discouraged me from pursuing nuclear engineering, learning about Molten Salt Reactors (MSRs) changed my perspective. Their passive safety features convinced me that nuclear energy could be both safe and beneficial for humanity.
How did your studies in Chemical Engineering at NTU provide you with the background to do a PhD in nuclear engineering?
Chemical engineering equipped me with the skills relevant for studying nuclear engineering. Engineering Math and Computational Methods enabled me to do simulation research, courses which I credit my professors, Dr Leslie and Dr Suraj, for making enjoyable. Heat Transfer, Fluids, Thermodynamics and Mass/ Energy Balance prepared me for thermal hydraulics research. My experiences at URECA and A*STAR gave me a solid foundation in research skills. I credit both for helping me transition into PhD life.
One of the greatest concerns about nuclear energy is safety. How does your work address the issue?
Safety is a broad and all-encompassing topic. A Hazard and Operability Study (HAZOP) of a chemical plant reveals that there are many potential risks in nuclear engineering. There is a process to identify contingencies a nuclear plant must withstand.
In general, we are concerned with station blackout (SBO), a situation in which a nuclear power plant loses all off-site power and on-site emergency power sources, which disrupts the ability to cool the reactor and manage decay heat. This is what happened at Fukushima.
While no official decision has been made on whether Singapore will go nuclear, the exploration of small modular reactors (SMRs) is already underway.
In Singapore, we need to ensure that a nuclear reactor emergency planning zone (EPZ) is ideally no bigger than the site boundary in case of an accident. Additionally, there are concerns regarding protection against missile strikes and similar threats.
My research deals mainly with managing reactor temperature during an SBO. In such cases, natural circulation must ensure the effective removal of decay heat in two types of reactors: Fluoride Salt Cooled High Temperature Reactors (FHR) and Pressurised Water Reactors (PWR). I have developed open-source natural circulation codes for FHRs and plan to extend this work to PWR natural circulation in the future.
What does your role at SNRSI entail, and what are the initiative's key goals for the coming years?
I’m tasked with research, education and outreach at SNRSI. The organisation has said it aims “to concentrate expertise and knowledge in nuclear technology and safety in a single institute, and to sustain a critical mass of manpower engaged in a range of nuclear-related activities relevant to Singapore.”
I interpret this as building a pool of researchers to investigate the feasibility of deploying nuclear technologies domestically.
While no official decision has been made on whether Singapore will go nuclear, the exploration of small modular reactors (SMRs) such as the NuScale SMR, the HTGR and molten salt reactors like the FHR is already underway.
The feasibility of underground deployment is also being studied. For a dense urban environment like Singapore, underground SMRs could provide a viable way to generate nuclear power while minimizing land use and safety risks.
Safety is the key priority in research. My current work extends off my PhD and builds simulations for molten salt natural circulation systems using the programming language Rust. There are also plans to study the simulation of light water reactor natural circulation, but this is significantly more challenging and will require more time.
With regards to outreach, I have previously coached teams for the International Nuclear Science Olympiad (INSO), a programme that cultivates young talent and provides talks on nuclear energy. I will also likely be involved in giving lectures in a local graduate programme for Nuclear Science and Technology.
What excites you most about the future of nuclear engineering and its safety?
It’s inspiring to see nuclear energy gaining traction worldwide, particularly in ASEAN.
Big Tech has played a role in this. Companies, like Microsoft, NVIDIA and more, have partnered with nuclear power companies and as a result, dispelled misconceptions about the tech.
For example, the amount of radiation exposure during a flight to Japan might be more than what you might receive while visiting any publicly accessible part of Fukushima.
Another exciting ongoing development is open-source coding for reactor thermal hydraulics as most codes in the past were inaccessible to most audiences. Open-source coding will democratise the industry and allow more people to contribute to the advancement of the field.
Outside of my current research, I'm also interested in how ionising radiation, which is typically associated with nuclear reactions, could be used in chemistry and chemical engineering. One example is a process called radiocatalysis, where gamma radiation is combined with catalysts to make ammonia from water and air. One recent study found this method to be more effective for producing ammonia than the widely used Haber process.
This effectively means we could use some radionuclides from nuclear waste to generate ammonia that can then be used as fuel, feedstock or even in carbon capture.
Bataan Nuclear Power Plant in the Philippines, photo taken by Ong while coaching for INSO
What advice would you give to young engineers and researchers aspiring to enter the nuclear field?
Being from SNRSI, I encourage you to consider our scholarship programme, which sends you abroad for master’s or PhD studies in nuclear science-related fields. We may also be doing a MSc programme in the future, so be on the lookout for it!
I’d also like to pass on advice I received from NTU Associate Professor Raymond Lau: Do not jump into a field just because its hot. Stay true to your interests and core competencies.
My other advice is to do your best wherever you are. Maximise the opportunities given, which may include classwork, internships or research projects. Stay focused on your work.
Finally, I want to encourage PhD students to take care of their mental health. It’s not unusual to need support and I encourage anyone struggling to seek help early. Learning to practice gratitude and grow in mental resilience is a journey.
Interview by Laura Dobberstein, NTU College of Engineering
This story first appeared in the NTU Engineering Annual Magazine, documenting the year 2024.
