Crowned Ridge Wind II, LLC, a wholly owned indirect subsidiary of NextEra Energy Resources (NEER), on April 11 filed with the South Dakota Public Utilities Commission an application for a facility permit in relation to Crowned Ridge’s proposal to build an approximately seven-mile, single-circuit, 230-kV generation tie line from the collector substation at the Crowned Ridge Wind II (CRW II) wind project to a dead-end transmission structure adjacent to the collector substation at Crowned Ridge Wind (CRW).
As noted in the application (Docket No. EL18-019), the purpose of the tie line (referred to as the project) – located in Codington County, S.D. – connecting the two wind projects is to allow for the generation from both wind projects to utilize one generation transmission tie corridor from the CRW collector substation to the Big Stone South 230-kV substation located near Big Stone, S.D.
Without the project connecting to the CRW collector substation, the generation from CRW II would require an additional generation transmission tie corridor and line from the CRW II collector substation to the Big Stone South 230-kV substation, which would add an entire new generation transmission tie corridor and line with additional impacts to the environment, aesthetics, and land, the application said.
Utilizing a breaker position at the CRW collector substation, the 300 MW from CRW II would be aggregated with the 300 MW from the CRW collector substation and conjoined to the Crowned Ridge 230-kV generation tie line, which would terminate at the reactive compensation substation adjacent to the Big Stone South substation, according to the application.
The 230-kV transmission line that connects the CRW collector substation to the Big Stone South substation is under review in Docket No. EL-17-50. The application further noted that it is anticipated that in June or July, separate applications for the facility permits to build the CRW and CRW II wind project will be filed.
CRW has executed a power purchase agreement (PPA) with Northern States Power (NSP) to sell NSP the full output of CRW, while CRW II has entered into a purchase and sale agreement under which it would permit and build CRW II and the project, and, thereafter, transfer the CRW II and the project, along with its facility permits to NSP at the commercial operations date.
The application added that the commercial operations dates for the CRW and CRW II are projected to be Dec. 31, 2019.
NSP’s PPA with CRW and the associated acquisition of CRW II are under consideration at the North Dakota Public Service Commission, the application noted, adding that on March 19, NSP and the North Dakota Public Service Commission staff requested that the proceeding be postponed until the record can be updated to reflect the impact of the 2017 Federal Tax Cuts and Jobs Act.
Crowned Ridge proposes to use tubular steel transmission structures for the project, with a typical height of about 100 feet. The project would have average spans between poles of 600 feet to 1,000 feet, although the spans would vary depending on geological or engineering constraints identified during final design, the application added.
The project’s permanent impacts would be about 50 square feet per pole, the application noted, adding that the project is expected to span wetlands and waterways wherever feasible, thereby minimizing direct impacts on those areas. Crowned Ridge is also working with landowners on their preferences for the placement of poles to minimize farming impacts.
The project begins at the 230-kV high side of the collector substation for CRW II, which is planned to be built on the southwest corner of the intersection of 166th Street and 465th Avenue, about 3.65 miles southeast of Waverly, S.D.
The application added that from the CRW II collector substation, the project heads west for .4 miles and turns north to cross 166th Street. After crossing that street, the project heads north for one mile, crosses 165th Street and immediately turns west to cross 464th Avenue for a total western run of .95 miles.
The project then turns north for .95 miles in its approach to crossing 164th Street, the application added, noting that the project crosses that street at a northwest angle and continues in the northwest direction for 1.1 miles. The project then turns north to cross 163rd and continues for .97 miles before making an immediate turn east for .93 miles on the south side of 162nd Street.
The application also said that the project then turns north to cross 162nd Street and continues for .76 miles to the project’s ending point at the dead-end transmission structure located across the street and adjacent to the CRW collector substation.
The project assists the overall 600 MW development plan by transporting 300 MW of generation from CRW II to the CRW collector substation where all 600 MW of generation is conjoined and further transported to the point of interconnection at the Big Stone South 230-kV substation. The application added that the 600 MW is comprised of three Midcontinent ISO (MISO) generation interconnection submittals that will utilize both the project and the 34-mile, 230-kV transmission line initiating at the collector substation of CRW.
CRW and CRW II have received signed generation interconnection agreements (GIA) for up to 400 MW of interconnection, the application noted, adding that the third 200-MW generation interconnection submittal is under study and Crowned Ridge anticipates receiving the final system impact study in May 2019. The final GIA is expected to be executed in a timely manner to ensure that any required transmission upgrades are completed so the transmission line may be interconnected to the Big Stone South substation before commercial operations.
Among other things, the application also noted that the estimated construction cost of the proposed seven-mile transmission line and associated facilities, including the 230-kV high-side of the CRW II collector substation, is about $10m.
As of the end of March, 89% of the transmission line route has been leased by Crowned Ridge, which expects to have all easements finalized by the end of April. The application further noted that the final design of the route, within a one-mile corridor, would be determined during negotiations with participating landowners, and placement of project facilities would be micro-sited to avoid or minimize impacts to environmental and cultural resources following field surveys.