U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

All Reports

Protection Against a Specific Type of Cyberattack

Report Number
2025-17542

Due to the importance of protecting the Tennessee Valley Authority (TVA) operations from external cyber events, we audited TVA’s protection mechanisms for a specific cyberattack.  Our objective was to determine if TVA’s protection mechanisms to prevent or protect against a specific type of cyberattack were adequately designed, properly implemented, and operating effectively.  Specifics are being withheld from public release due to their sensitive nature in relation to TVA’s cybersecurity.  We made two recommendations to TVA management. 

Audit

TVA Penetration Test

Report Number
2025-17581

Due to the importance of security measures required to protect the Tennessee Valley Authority’s (TVA) information and operations from cybersecurity threats, the OIG performed a penetration test of TVA’s network, systems, and applications.  Our objective was to determine if vulnerabilities and other cybersecurity weaknesses in TVA’s network, systems, and applications were present and exploitable. Specifics are being withheld from public release due to their sensitive nature in relation to TVA’s cybersecurity. We made five recommendations to TVA management.

Audit

TVA Demand Response

Report Number
2025-17554

Demand Response (DR) programs offer incentives for electric utility customers to reduce their energy use during peak demand which reduces the need for generation and helps offset market purchases during times of peak cost.  TVA is expanding its portfolio and plans to invest more than $1.5 billion in its Energy Efficiency and DR programs from fiscal year (FY) 2024 through FY 2028.  Due to the risk of TVA’s investment not meeting the anticipated reduction in energy needs, we performed an evaluation to determine if TVA's investment in DR programs was delivering intended benefit

Inspection / Evaluation

Hydro Life Extension

Report Number
2025-17564

The Tennessee Valley Authority (TVA) has 109 conventional hydroelectric generating units with a capacity of 3,783 megawatts (MW). The hydro fleet supports TVA’s mission of providing clean, reliable, and affordable electricity to people and businesses of the Tennessee Valley.  As of 2021, 53 of TVA’s 109 hydro units had low asset health scores indicating the need for repair.  To extend the life of the hydro fleet, the Hydro Life Extension (HLE) program was formed in 2021.  Due to the importance of TVA’s hydro fleet in providing low cost, clean, and

Inspection / Evaluation

Semiannual Report – April 1, 2025 – September 30, 2025

We are pleased to present our report for the period April 1, 2025, to September 30, 2025.  In this semiannual period, our audit, evaluation, and investigative activities identified more than $31.4 million in questioned costs; funds to be put to better use; recoveries, fees, and savings; and opportunities for the Tennessee Valley Authority (TVA) to improve its programs and operations.  This report also includes a feature, “40 Years of Making TVA Better,” that looks back at the last four decades—the environment TVA operated in each decade and the Inspectors General t

Semiannual Report

Monitoring of Ernst & Young LLP’s Audit of the Tennessee Valley Authority Fiscal Year 2025 Financial Statements

Report Number
2025-17590

In keeping with its responsibilities under the Inspector General Act of 1978, as amended, the OIG monitored the audit of TVA's fiscal year 2025 financial statements performed by Ernst and Young LLP (EY) to assure their work complied with Government Auditing Standards. Our review of EY's work disclosed no instance in which the firm did not comply in all material respects with Government Auditing Standards.

Audit

Kiewit Power Constructors Company - Contract No. 13156

Report Number
2025-17534

We performed an audit of costs billed to the Tennessee Valley Authority (TVA) by Kiewit Power Constructors Company (Kiewit) under Contract No. 13156 for work performed in support of TVA’s coal combustion residual conversion program.  Our audit objective was to determine if the costs billed to TVA were in accordance with the contract’s terms.  Our audit scope included approximately $133.7 million in costs billed to TVA between January 1, 2023, and September 30, 2024.

Audit

Agreed-Upon Procedures for TVA Fiscal Year 2025 Performance Measures

Report Number
2025-17597

The Office of the Inspector General (OIG) performed the procedures, which were requested and agreed to by Tennessee Valley Authority management solely to assist management in determining the validity of the Winning Performance (WP)/Executive Annual Incentive Plan measures for fiscal year (FY) ending September 30, 2025.  Tennessee Valley Authority management is responsible for the WP measures data provided. In summary, procedures applied by the OIG found the:

Other

Oversight of Contractor Safety

Report Number
2025-17547

The Occupational Safety and Health Administration states that establishing a safety and health program is one of the most effective ways of protecting workers.  The Tennessee Valley Authority (TVA) Standard Programs and Processes (SPP) 18.004, Contractor Safety Management, establishes the contractor safety program and defines oversight requirements for managed task contractors and subcontractors working on TVA-owned-or-controlled sites to meet state and federal safety and health regulations.  

Inspection / Evaluation

Shawnee Selective Catalytic Reduction Project

Report Number
2025-17563

The Tennessee Valley Authority (TVA) operates four coal plants, which are required to comply with the Clean Air Act (CAA).  In 2023, changes to the CAA required the reduction of nitrogen oxide (NOx) from power plants.  To comply with the changes, TVA made the decision to install Selective Catalytic Reduction (SCR) systems at TVA’s Shawnee Fossil Plant (SHF) for Units 2, 3, 7, and 8 and entered into a $59.5 million contract for the design and delivery of SCR systems (SCR systems are emission control technology designed to remove NOx from flue gases emitted by combus

Inspection / Evaluation