"Performance and Safety Analysis of a Generic Small Modular Reactor ,"
M.S. Thesis, Nuclear Engineering, Texas A&M University, College Station, TX (2012).
The high and ever growing demand for
electricity coupled with environmental concerns and a worldwide
desire to shed petroleum dependence, all point to a shift to
utilization of renewable sources of energy. The under developed
nature of truly renewable energy sources such as, wind and solar,
along with their limitations on the areas of applicability and the
energy output calls for a renaissance in nuclear energy. In this
second nuclear era, deliberately small reactors are poised to play
a major role with a number of Small Modular Reactors (SMRs)
currently under development in the U.S.
In this work, an SMR model of the Integral
Pressurized Water Reactor (IPWR) type is created, analyzed and
optimized to meet the publically available performance criteria of
the mPower SMR from B&W.
The Monte Carlo codes MCNP5/MCNPX are used
to model the core. Fuel enrichment, core inventory, core size are
all variables optimized to meet the set goals of core lifetime and
fuel utilization (burnup). Vital core behavior characteristics such
as delayed neutron fraction and reactivity coefficients are
calculated and shown to be typical of larger PWR systems, which is
necessary to ensure the inherent safety and to achieve rapid
deployment of the reactor by leveraging the vast body of
operational experience amassed with the larger commercial
Inherent safety of the model is analyzed
with the results of an analytical single channel analysis showing
promising behavior in terms of axial and radial fuel element
temperature distributions, the critical heat flux, and the
departure from nucleate boiling ratio.
The new fleet of proposed SMRs is intended
to have increased proliferation resistance (PR) compared to the
existing fleet of operating commercial PWRs. To quantify this PR
gain, a PR analysis is performed using the Proliferation Resistance
Analysis and Evaluation Tool for Observed Risk (PRAETOR) code
developed by the Nuclear Science and Security Policy Institute at
Texas A&M University. The PRAETOR code uses multi-attribute
utility analysis to combine 63 factors affecting the PR value of a
facility into a single metric which is easily comparable. The
analysis compared hypothetical spent fuel storage facilities for
the SMR model spent fuel assembly and one for spent fuel from a
Westinghouse AP1000. The results showed that from a fuel material
standpoint, the SMR and AP1000 had effectively the same PR value.
Unable to analyze security systems and methods employed at specific
nuclear power plant sites, it is premature to conclude that the SMR
plants will not indeed show increased PR as intended.
Associated Project(s):Safety, Proliferation, and Economics Assessment of Small Modular Reactors