U.S. Energy Information Administration logo
Skip to sub-navigation

NEMS - National Energy Modeling System: An Overview

May 2023


The National Energy Modeling System: An Overview (Overview) provides a summary of the National Energy Modeling System (NEMS), which makes projections published in our Annual Energy Outlook (AEO).

NEMS is an energy-economy modeling system of U.S. energy markets for the period extending through 2050. This model projects the production, imports, exports, conversion, consumption, and prices of energy, subject to a number of assumptions. The assumptions encompass macroeconomic and financial factors, world energy markets, resource availability and costs, behavioral and technological choice criteria, technology characteristics, and demographics. NEMS produces a general equilibrium solution for energy supply and demand in the U.S. energy markets on an annual basis.

Our Office of Energy Analysis develops and maintains NEMS, and analysts perform policy analyses requested by decision makers in the White House; the U.S. Congress; offices within the U.S. Department of Energy, including program offices; and other government agencies. NEMS was first used for projections presented in the AEO1994.

This NEMS documentation page has more details about each module. The Assumptions page contains separate reports about the latest assumptions for each module.

See full report