cyclus

Cyclus is the Latin term for a circle or cycle and is used in various fields to denote repeating processes. In modern usage, cyclus may refer to cyclical phenomena generally, or as a proper noun for a software project focused on nuclear fuel-cycle analysis.

Cyclus is an open-source nuclear fuel-cycle simulator designed to model and analyze how different fuel-cycle options perform over time. It employs an agent-based modeling approach in which entities such as facilities and institutions act as agents, managing inventories of nuclear materials and carrying out operations like mining, conversion, enrichment, fabrication, irradiation, recycling, and disposal. Simulations are defined as networks of facilities, markets, and policies, and progress by discrete time steps to reveal material flows, costs, and capacity utilization. The software is built for modularity, with facility templates, policy modules, and plug-ins that can be combined to form diverse scenarios.

Applications include policy analysis, research, and education. Users compare reactor fleets, fuel-source mixes, recycling strategies, and waste-management approaches; perform sensitivity analyses and optimization; and visualize outcomes such as material stocks, flows, and economic indicators across regions and time horizons.

Cyclus is developed collaboratively by researchers and institutions and is distributed as open-source software. It is intended to be vendor-agnostic and extensible, supported by a user community and documentation. The project aims to facilitate transparent, repeatable analysis of long-term nuclear fuel-cycle options.