Title: Feasibility of Small Modular and Micro Reactors in Hybrid Energy Systems

Program: Civil Engineering MS

Committee Chair: Mojtaba Sadegh

Committee: Mojtaba Sadegh, Kathleen Araujo, Bhaskar Chittoori

Abstract: This thesis evaluates the feasibility of integrating next-generation nuclear technology into a hybrid energy system, framing the analysis within the guidelines suggested by the World Energy Council’s, Energy Trilemma. The trilemma seeks to balance energy security, economics/equity and sustainability. To this end, a computer model was created to illustrate how the challenges posed by the intermittent nature of renewables like wind and solar (PV) can be addressed when they are combined with a baseload provided by a next-generation nuclear Small Modular Reactor (SMR). The baseload provided by nuclear energy aims to stabilize a variable generation system with a reliable baseload, while simultaneously offsetting the cost of nuclear energy with the low cost of renewable energy. Using the System Advisor Model (SAM) with data from the Idaho National Laboratory (INL) and Lazard’s Levelized Cost of Electricity+ 2024, four modeled scenarios were developed to test the hypothesis that incorporating a nuclear baseload can reduce system variability and offset costs.
The analysis demonstrated that the modeled 62 MW renewables-only system had a low-capacity factor of 24.77%, and a real Levelized Cost of Electricity (LCOE) of $168.35/MWh. When a 20 MW SMR was added to the same renewables-only system, the capacity factor increased to 41.17% while the LCOE decreased to $166.84/MWh, validating the hypothesis. Simulations show that renewables and SMR can complement each other and address their individual weaknesses, making a more reliable and economic energy portfolio. Since the focus was on hybrid energy, the same renewable system was modeled with a 20 MW utility scale battery, which resulted in high LCOE of $243.16/MWh. While a comprehensive analysis of the Levelized Cost of Storage (LCOS) is out of the scope of this study, this scenario highlights the challenges associated with short-term strategies that do not properly address the root cause of a problem.
The findings concluded that pairing nuclear energy with a renewable-hybrid system can indeed create a resilient, affordable and sustainable energy portfolio that effectively addresses the complex demands of the energy trilemma. This study highlights the potential for next-generation nuclear technology to play a central role in future energy systems.