On May 11, 2009, the Commission approved tariff revisions made by the New York Independent System Operator, Inc. (“NYISO”) that will treat wind resources as flexible resources. The revisions will require wind resources to “dispatch down” in order to resolve transmission system constraints.
Previously, NYISO’s real-time-dispatch software could not direct wind resources to dispatch down even if doing so would have relieved the system of various constraints. Instead, NYISO’s software would have other flexible resources dispatch down. If no other flexible resources were available, NYISO would have to manually identify the wind resources that could eventually be turned offline. Alternatively, wind generators could decide to reduce their output if they were receiving negative power prices. However, such sudden reductions in output could lead to reliability issues because the output is often removed for longer periods of time than what is necessary.
On March 5, NYISO submitted tariff revisions to the Commission to help resolve these problems. In addition to treating wind resources as flexible resources, NYISO also required wind generators to submit prices at which they will reduce their generation. NYISO also had to adjust its market settlement rules as they apply to wind resources. These rules proposed that if a wind resource receives a dispatch down order, it will be subject to the same settlement rules applied to non-wind resources that generate above their real-time schedules.
NYISO’s application also requested an effective date of May 12 for the new flexible resources rule. NYISO admitted that the necessary communications equipment would not be ready on May 12, but that the software would still be able to identify which wind resources needed to be reduced. Thus, the dispatch-down instructions could be relayed manually until all of the necessary communications equipment was installed. Meanwhile, NYISO requested that the settlement rules have an effective date of November 1 for all but one wind resource, which would need more time to install necessary communications systems.
The Commission accepted NYISO’s proposed revisions and noted that NYISO’s enhanced control over wind resources should improve efficiency and increase reliability. A copy of the Commission’s order can be found at http://www.ferc.gov/ under Docket No. ER09-802.