The Texas grid operator has more than tripled its pace of completing utility-scale solar interconnection studies since 2019. Yet the battery backlog continues to grow.
August 7, 2020
The ERCOT grid operator that serves most of Texas has completed full interconnection studies for 58 solar projects totaling 11.9 GW of capacity so far this year. The completed studies will allow project developers to proceed toward commercial operation.
In the first seven months of this year, ERCOT has already completed nearly twice as many solar interconnection studies, for nearly twice as much solar capacity, as it did in all of 2019.
These data reflect an analysis of ERCOTâs Generator Interconnection Status reports for December 2019 and July 2020.
Contributing to this dramatic increase in productivity, said an ERCOT spokesperson, is a resource integration group that ERCOT formed, with staff from the operations, planning and grid coordination functions, to help streamline the interconnection process. ERCOT also created new tools to aid its staff and market participants in processing interconnection requests, she said.
The spokesperson credited transmission service providers for doing âmost of the workâ on full integration studies, while ERCOT staff âis responsible for reviewing and approving FIS studies.â
ERCOT has been reducing its count of full interconnection studies underway since about February, as shown by the shrinking light blue bars in this ERCOT graph:
ERCOTâs solar workload remains high, because so far this year solar developers have requested full studies for 49 projects totaling 13.3 GW. At last count, ERCOT had about 2.7 GW of utility-scale solar capacity.
Battery projects languish
ERCOTâs battery queue has grown to about 9 GW. Developers of 32 battery projects totaling 4.9 GW have requested full studies this year, while ERCOT has completed only 9 such studies this year, for projects totaling 0.7 GW. In 2019 ERCOT approved only two battery projects for 0.25 GW, while it received 43 requests for full studies, representing 4.1 GW.
ERCOTâs 2019 âState of the Gridâ report says that the grid operator has created a battery energy storage task force, and staff have begun exploring technical requirements, modeling needs and market rules for battery storage.
ERCOTâs wind queue is stable, with 15 wind projects totaling 2.5 GW approved since January, and developers of ten wind projects totaling 2.4 GW requesting full studies since then.
For a solar project developer, ERCOTâs full interconnection study is a major hurdle, and requires payment of the second and larger of two interconnection fees to ERCOT. A developer must complete many other steps after ERCOT completes a full study, including work with the transmission service provider to connect the project to the grid.
Milestones in ERCOTâs interconnection process are shown below, with the full interconnection study shown in the middle of the top row:
ERCOT interconnection data were analyzed for this story by Driscoll Consulting LLC, a firm owned by the author. An ERCOT spokesperson said that staff reviewed the solar and battery data, which were provided in a press inquiry, and found the data to be âclose to what weâre showing in our system.â The spokesperson said that ERCOT staff can make changes to FIS approval dates over time, âand as a result, comparing an older GIS report with a new one may result in some differences. As an example, technology changes could require additional studies which would in turn impact the FIS approval date.â