Preliminary Analysis and Case Study of Transmission Constraints and Wind Energy in the West: Preprint

Wind developers typically need long-term transmission service to finance their projects; however, most of the capacity on several key paths is reserved by existing firm contracts. Because non-firm contracts are only offered for periods up to 1 year, obtaining financing for the wind project is generally not possible when firm capacity is unavailable. However, sufficient capacity may exist on theconstrained paths for new wind projects that can risk curtailment for a small number of hours of the year. This paper presents the results of a study sponsored by the National Renewable Energy Laboratory (NREL), a work group participant in the Rocky Mountain Area Transmission Study (RMATS). Using recent historical power flow data, case studies were conducted on the constrained paths betweenWyoming-Colorado (TOT3) and Montana-Northwest, coinciding with areas of exceptional wind resources. The potential curtailment frequency for hypothetical 100-MW and 500-MW wind plants was calculated using hourly wind data. The results from the study indicate that sufficient potential exists for innovative transmission products that can help bring more wind to load centers and increase theefficiency of the existing transmission network.