Wind Project Performance 1994 Summary
Although wind project operators from five different resource areas in California reported to WPRS, about 95 percent of all California capacity and output is generated in only three resource areas: Altamont, San Gorgonio and Tehachapi. All three of these areas are narrow mountain passes leading into hot valley or desert regions. Among these three resource areas, 39 percent of all capacity is found in Tehachapi, more than 38 percent in Altamont, and about 17 percent in San Gorgonio resource areas (Figure 7 -- Resources Area Capacity).
When resource area capacity (Figure 7) and percent of total statewide output (Figure 8 -- Resource Area Output [Millions of kWh]) for the three primary resource areas are compared, Tehachapi (41 percent output at 39 percent capacity) and San Gorgonio (19 percent output at 17 percent capacity) produced more than their shares, and Altamont (36 percent output at 38 percent capacity) produced less than its share.
Of the three largest resource areas, San Gorgonio had the highest capacity factor (28 percent), followed by Tehachapi (24 percent) and Altamont (20 percent). Solano and Pacheco, two smaller resource areas, had capacity factors of 19 percent and 18 percent respectively (Figure 9 -- Capacaity Factor by Resource Area).
When comparing resource area performance, many factors should be considered. For example, age of equipment appears to be a significant factor affecting the performance difference between San Gorgonio and Altamont. The Altamont resource area includes two large developers with about 103 MW of very old capacity and only a 6 percent average capacity factor, significantly lowering Altamont's overall performance. San Gorgonio wind developers met substantial delays getting local government approval for their projects, thus their equipment is newer.