Step 5: Final Transmission Plan Designation

The appropriate authorities (such as a regulatory authority or ministry of energy) may need to ensure specific reliability and other requirements before selecting the final transmission plan from the set of previously considered transmission development options from step 4. To select the most appropriate option, the Transmission WG and TAC make an interim selection of a transmission option—with the information provided by the system operator from step 4—pending full reliability modeling results. Finally, in step 5 the regulatory authority designates the final transmission plan to be implemented. 

Perform a full reliability analysis

The Transmission WG and TAC perform reliability and ancillary cost impact analyses on the selected transmission option and disclose any major problems. The appropriate authorities use these reliability analysis and modeling results together to determine whether the selected transmission plan meets all requirements to issue a final transmission order.

Issue final transmission order

The regulatory authority’s final order memorializes and authorizes the body of decisions made throughout the REZ process. This means including the selected transmission enhancements in official transmission planning documents. The designation includes a geographic description of the selected REZs; identifies major transmission improvements needed to cost-effectively deliver the electricity; identifies who will pay for the transmission improvements; and updates the estimate of the maximum generating capacity in the REZs based on capacity upgrades. The figure below is a map of the REZs and new transmission infrastructure necessary to access these zones as identified through the Texas CREZ process.

Figure. REZs and new transmission infrastructure necessary to access these zones identified in the Texas CREZ process (Hurlbut et al. 2016)