The company was formerly known as
TXU Electric Delivery and TU Electric. Predecessor companies include Dallas Power & Light (DP&L), which served the city of Dallas; Texas Electric Service Company (TESCO), which served areas surrounding Fort Worth; and Texas Power and Light (TP&L), which served other areas of northwest and east-central Texas. Oncor is TXU electric delivery replacing analog meters in 2008 with digital meters throughout its system, although some older analog meters remain. Oncor was privately held by a limited number of investors, including
Energy Future Holdings Corporation (EFH), and separately managed by a majority independent board of directors. While a majority owner, EFH was not involved in the management of Oncor. On March 24, 2016, the
Texas Public Utility Commission (PUC) granted the request to convert Oncor into a
real estate investment trust (REIT) with the reservation that the PUC would consider the treatment of potential tax savings (estimated at $250 million) from the REIT structure in a separate proceeding to be held at a future date. The subsequent proceeding's focus was to determine how the potential tax savings attributable to the REIT format would be shared with utility ratepayers. On July 7, 2017, it was announced that
Berkshire Hathaway had agreed on a deal to buy the whole of Energy Future Holdings and ultimately Oncor. This bid was ultimately surpassed by Sempra Energy, which bid $9.45 billion in cash and the assumption of debt on August 21, 2017. The acceptance of the Sempra bid effectively terminated the Berkshire bid. The Sempra bid subsequently received court approval on September 6, 2017. On March 8, 2018, regulators in Texas approved Sempra Energy's purchase of a majority stake in Oncor for $9.45 billion. ==Major projects==