A review of existing analysis codes for nuclear fuel cycle systems was performed to determine if any existing codes meet technical and functional requirements defined for a U.S. national program supporting the global and domestic assessment, development, and deployment of nuclear energy systems. The program would be implemented using an interconnected architecture of different codes ranging from the fuel cycle analysis code, which is the subject of the review, to fundamental physical and mechanistic codes. Four main functions are defined for the code. Function 1 is the ability to characterize and deploy individual fuel cycle facilities and reactors in a simulation while discretely tracking material movements. Function 2 is the capability to perform an uncertainty analysis for each element of the fuel cycle and an aggregate uncertainty analysis. Function 3 is the inclusion of an optimization engine able to optimize simultaneously across multiple objective functions. Function 4 is open and accessible code software and documentation to aid in collaboration between multiple entities and to facilitate software updates.

Existing codes, categorized as annualized or discrete fuel tracking codes, were assessed according to the four functions and associated requirements. These codes were developed by various government, education, and industrial entities to fulfill particular needs. In some cases, decisions were made during code development to limit the level of detail included in a code to ease its use or to focus on certain aspects of a fuel cycle to address specific questions. The review revealed that while no two of the codes are identical, they all perform many of the same basic functions. No code was able to perform defined function 2 or several requirements of functions 1 and 3. Based on this review, it was concluded that the functions and requirements will be met only with development of a new code, referred to as GENIUS.