NOTICE DATE: May 8, 2012 NOTICE TYPE: M-A040612-03 NPRR SHORT DESCRIPTION: REMINDER - Implementation details of NPRR434 INTENDED AUDIENCE: ERCOT Market Participants DAY AFFECTED: Operating Day May 10, 2012 LONG DESCRIPTION: Effective starting on Operating Day May 10, 2012, ERCOT will implement Nodal Protocol Revision Request (NPRR) 434, Increase the Capacity Limitation of a Generation Resource Providing RRS, which was approved by the ERCOT Board on February 21, 2012. NPRR434 increases the maximum amount of Responsive Reserve (RRS) that can be provided by a Generation Resource from 20% to 24% of its High Sustained Limit (HSL). The Day-Ahead Market results on May 9, 2012, for Operating Day May 10, 2012, will reflect the increased RRS percentage. ADDITIONAL INFORMATION: NPRR434 and associated documents can be found on the ERCOT website, under Market Rules, at http://www.ercot.com/mktrules/issues/nprr/426-450/434/index. Information on upcoming releases can be found on the ERCOT Multi Year Project Priority List (PPL) at http://www.ercot.com/services/projects/. CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at [log in to unmask]<mailto:[log in to unmask]>. If you are receiving email from an ERCOT distribution list that you no longer wish to receive, please follow this link in order to unsubscribe from this list: http://lists.ercot.com. dh