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Documentation of the National Energy Modeling System (NEMS) modules

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A brief introduction of the National Energy Modeling System (NEMS) is available on the Assumptions page. A more detailed overview is provided below in the report: The National Energy Modeling System: An Overview.

NEMS consists of 13 modules: 4 supply modules (Oil and Gas Supply, Natural Gas Market, Coal Market, and Renewable Fuels); 2 conversion modules (Electricity Markets and Liquid Fuels Markets (that is, refineries); 4 demand modules (Residential Demand, Commercial Demand, Transportation Sector, and Industrial Demand); 1 module to simulate energy/economy interactions (Macroeconomic Activity); 1 to simulate world/domestic liquids interactions (International Energy); and 1 module that provides the mechanism to achieve a general market equilibrium among all the modules (Integrating). These modules are documented below.

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  • Notes:
    [1] The Liquid Fuels Market Module replaced the Petroleum Market Module starting with Annual Energy Outlook 2013.
    [2] The Natural Gas Market Module replaced the Natural Gas Transmission and Distribution Module starting with Annual Energy Outlook 2018.