from left to right: Dr. Bourham, Dr. Doster, Dr. Frick and Dr. Terry

Konor Frick successfully defends PhD dissertation

On January 29, 2018, Konor Logan Frick successfully defended his PhD dissertation, Modeling and Design of a Sensible Heat Thermal Energy Storage System for Small Modular Reactors. Konor’s PhD committee consisted of his advisor, J. Michael Doster, and members, Mohamed Bourham, Steve Terry, and Shannon Bragg-Sitton of Idaho National Laboratory. 

Konor earned both his Bachelor of Science and Master of Science in Nuclear Engineering from North Carolina State University. He was designated as a CASL Undergraduate Research Scholar and successfully completed two distinct appointments. Upon graduating summa cum laude with his undergraduate degree in 2014, Konor was awarded a Nuclear Energy University Program (NEUP) Fellowship by the U.S. Department of Energy to continue his studies in graduate school. Since entering graduate school, Konor has been selected to present his research at four ANS national conferences, authored seven papers, coauthored two publications, and been inducted into Sigma Xi, the Scientific Research Honor Society. Konor is currently residing at Idaho National Laboratory after being chosen as one of the first recipients of their competitive Graduate Fellows Program.

Abstract

FRICK, KONOR L. Modeling and Design of a Sensible Heat Thermal Energy Storage System for Small Modular Reactors. (Under the direction of Dr. J. Michael Doster.)

The contribution of intermittent (renewable) energy sources such as wind and solar continues to increase as renewables improve in efficiency and price-point. However, the variability of renewables generates additional challenges for the electric grid in the form of rapidly varying electric loads.

Proposed options for accommodating this load have included operating nuclear reactors in a load follow mode, or operating the reactor at or near steady state and bypassing steam directly to the condenser. Both of these strategies result in lost energy potential. In addition to lost energy potential, load follow operation results in increased stress on the fuel and other mechanical components.  A more attractive approach is to operate the reactor at or near steady state and bypass excess steam to a thermal energy storage system. The thermal energy can then be recovered later, either for electric generation during periods of peak electric demand, or for use in ancillary applications such as desalination and chilled water production. Such systems are known as nuclear hybrid energy systems (NHES). Various methods of Thermal Energy Storage (TES) can be coupled to nuclear (or renewable) power sources to help absorb grid instabilities caused by daily electric demand changes and renewable intermittency.

Sensible Heat Thermal Energy Storage is a mature technology currently used in solar energy systems. This research focuses on the design and coupling of such a system to Small Modular Reactors (SMRs), typical of Integral Pressurized Water Reactor (IPWR) designs currently under development.

The goal of the coupled system is to match turbine output with demand, bypass steam to the TES system for storage, and maintain reactor power at approximately 100%. Simulations of the NHES dynamics are run in a high-fidelity FORTRAN model developed at NCSU.  Results reveal a sensible heat storage system is capable of meeting turbine demand and maintaining reactor power constant, while providing enough thermal energy to operate the TES system as an electric or steam peaking unit.