---
kind: "unit"
title: "10"
title_heading: "Energy"
key: "chII/subchE/part500"
level: "part"
label: "Part 500"
heading: "Definitions"
release: "ecfr-current"
date: "2026-08-27"
url: "https://uscodex.org/cfr/10/chII-subchE-part500"
sections_count: 3
---

# Part 500 — Definitions

Title 10 C.F.R. — Energy › Chapter II — Department of Energy › Subchapter E — Alternate Fuels

## Sections

- [§500.1. Purpose and scope.](/cfr/10/500.1.md)
- [§500.2. General definitions.](/cfr/10/500.2.md)
- [§500.3. Electric regions—electric region groupings for reliability measurements under the Powerplant and Industrial Fuel Use Act of 1978.](/cfr/10/500.3.md)