The U.S. code pertaining to the Department of Energy is in title 42, chapter 84.
Westlaw and Lexis provide online access to their published annotated U.S. Code; the text of the code and the annotations are updated regularly.
A free U.S. Code can be found online at the Office of Law Revision Council United States Code page, as well as the Legal Information Institute.
A simple list of the Department of Energy administers can be found here.
The annotated Code of Federal Regulations (CFR) can be found on Westlaw and Lexis. The online annotated CFR will have the most up to date annotations.
The non-annotated CFR can be found at the Legal Information Institute and the Government Printing Office's eCFR.
For general information about administrative agencies and how they make regulations, see our Administrative Law Research Guide and Administrative Law Research Tutorial.
Access to Annotated State Code and Regulations
Westlaw and Lexis provide access to annotated state code; the annotated codes are found within each states' page.
State Administrative Code Collections
Lexis: State page > Administrative Materials, Codes and Regulations
Westlaw: State page > Regulations
Freely Available Collections
States and municipalities' websites typically provide access to state code and regulations.
Legal Information Institute: State Statutes Related to Utilities and Transportation.
This page provides links to the full text of state utilities law statutes that are freely available on the web. The currency of linked statutes varies.