The National Energy Modeling System (NEMS) is a long-term energy-economy modeling system of U.S. energy markets. The model is used to project production, imports, exports, conversion, consumption, and prices of energy, subject to user-defined assumptions. The assumptions encompass macroeconomic and financial factors, world energy markets, resource availability and costs, behavioral and technological choice criteria, technology characteristics, and demographics.
This version of NEMS is based on the version used for AEO2025, with updated software dependencies, and updates to several series contained in the restart file.