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As of July 5, 2022, we have restored most of our data publications. See a complete list of releases for the week. We will not publish U.S. diesel prices today. We will continue to provide updates regarding the status of diesel prices and other data products.

Glossary

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A B C D E F G H I J K L M N O P Q R S T U V W XYZ

Browse terms related to these fuel groups:alternative fuels|coal|electricity|natural gas|nuclear|petroleum|renewable

derate

Derate:  A decrease in the available capacity of an electric generating unit, commonly due to:

• A system or equipment modification
• Environmental, operational, or reliability considerations. Causes of generator capacity deratings include high cooling water temperatures, equipment degradation, and historical performance during peak demand periods. In this context, a derate is typically temporary and due to transient conditions.

The term derate can also refer to discounting a portion of a generating units capacity for planning purposes.

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