Tex. Util. Code § 36.051 : Utilities Code — Public Utility Regulatory Act — Electric Utilities — Rates — Computation Of Rates — Establishing Overall Revenues

In establishing an electric utility's rates, the regulatory authority shall establish the utility's overall revenues at an amount that will permit the utility a reasonable opportunity to earn a reasonable return on the utility's invested capital used and useful in providing service to the public in excess of the utility's reasonable and necessary operating expenses.