All Reports

Due to the risk of harm to the Tennessee Valley Authority (TVA) from the loss or breach of private information held by a third party, we performed an audit of BlueCross BlueShield of Tennessee’s (BCBST) security controls.  Our audit objective was to determine if BCBST has controls in place to meet contract requirements for the protection of data held by the vendor on behalf of TVA.

Due to the importance of protecting the Tennessee Valley Authority’s (TVA) operations from external cyber events, we performed an audit of TVA’s transmission control center network cybersecurity. The audit objective was to determine if TVA has sustainable processes for identifying, implementing, and managing the network architecture to reduce the overall cybersecurity risk to TVA resources in their transmission networks.  The audit scope was limited to TVA’s transmission control center network.  We made one recommendation to TVA management. The specifics are being

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. 

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.

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

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

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

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.

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.

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: