(a) If an electric utility chooses on or after January 1, 2007, to participate in customer choice, the commission may not authorize customer choice until the applicable power region has been certified as a qualifying power region under § 39.152(a). Except as otherwise provided by this subsection, the commission shall certify that the requirements of § 39.152(a)(3) are met for electric utilities subject to this subchapter only upon a finding that the total capacity owned and controlled by each such electric utility and its affiliates does not exceed 20 percent of the total installed generation capacity within the constrained geographic region served by each such electric utility plus the total available transmission capacity capable of delivering firm power and energy to that constrained geographic region. Not later than May 1, 2002, each electric utility subject to this subchapter shall submit to the electric utility restructuring legislative oversight committee an analysis of the needed transmission facilities necessary to make the electric utility’s service area transmission capability comparable to areas within the ERCOT power region. On or after September 1, 2003, each electric utility subject to this subchapter shall file the utility’s plans to develop the utility’s transmission interconnections with the utility’s power region or other adjacent power regions. The commission shall review the plan and not later than the 180th day after the date the plan is filed, determine the additional transmission facilities necessary to provide access to power and energy that is comparable to the access provided in areas within the ERCOT power region; provided, however, that if a hearing is requested by any party to the proceeding, the 180-day deadline will be extended one day for each day of hearings. The commission shall, as a part of the commission’s approval of the plan, approve a rate rider mechanism for the recovery of the incremental costs of those facilities after the facilities are completed and in-service. A finding of need under this subsection shall meet the requirements of Sections 37.056(c)(1), (2), and (4)(E). The commission may certify that the requirements of § 39.152(a)(3) are met for electric utilities subject to this subchapter if the commission finds that:
(1) each such utility has sufficient transmission facilities to provide customers access to power and energy from capacity controlled by suppliers not affiliated with the incumbent utility that is comparable to the access to power and energy from capacity controlled by suppliers not affiliated with the incumbent utilities in areas of the ERCOT power region; and
(2) the total capacity owned and controlled by each such electric utility and its affiliates does not exceed 20 percent of the total installed generation capacity within the power region.
(b) In the area of a power region served by an electric utility subject to this subchapter, the electric utility may not choose to participate in customer choice unless the affiliated power generation company makes a commitment to maintain and does maintain rates that are based on cost of service for any electric cooperative or municipally owned utility that was a wholesale customer on the date the utility chooses to participate in customer choice and was purchasing power at rates that were based on cost of service. This subsection requires a power generation company to sell power at rates that are based on cost of service, notwithstanding the expiration of a contract for that service, until the requirements of § 39.152(a) are met.

(c) If the requirements of § 39.152(a) have not been met for an electric utility subject to this subchapter when the electric utility chooses to participate in customer choice, then any power generation company in the power region affiliated with an electric utility subject to this subchapter shall maintain adequate supply and facilities to provide electric service to persons who were retail customers of the electric utility on the date the utility chooses to participate in customer choice. The obligation provided by this subsection remains in effect until the commission determines that the requirements of § 39.152(a) have been met for the region.