An official website of the United States government.

We've made some changes to If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Clean Air Markets

NEEDS v.5.15 User Guide

View a user guide for the the updated National Electric Energy Data System (NEEDS), the database used to construct the "model" plants that represent existing and planned/committed units in EPA modeling applications.

View Power Sector Modeling Platform v.5.15 for related information.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.