Incorporating Solar Resource Real-Time Data Requirements into Market Rule 1

1. May 7-8, 2019 | westborough, MA Jonathan Lowell jlowell@iso-ne.com | 413-540-4658 Incorporating Solar Resource Real-Time Data Requirements into Market Rule 1 Solar Data Requirements

2. Solar Data Requirements WMPP ID: 137 Proposed Effective Date: October 2019 For situational awareness and efficient system dispatch, real-time meteorological telemetry from solar resources will be important as grid-connected solar penetration increases ISO is proposing to establish real-time data telemetry requirements for solar resources that are nearly identical to existing wind resource data requirements contained in the Large Generator Interconnection Agreement (LGIA). Requirements for both solar and wind will now be consolidated in a new location in Market Rule 1 (MR-1) Today’s presentation will focus on: • Historical background • Rationale for relocating requirements from LGIA to MR-1 • Summary of who is affected

3. Background – Wind Resources, Operating Procedure 14 & FERC Order 764 In 2011 the ISO established data requirements for wind resources that are represented in the ISO’s network model and dispatch software. These requirements were documented in Operating Procedure 14 (OP14) Appendix F FERC Order 764 (Integration of Variable Energy Resources, issued 6/22/2012) required meteorological and outage related data requirements to be included in the tariff, specifically in the LGIA. This was accomplished in 2014 These wind data requirements play an important role supporting the ISO’s short-term wind forecast, which allows wind to be dispatched under the Do Not Exceed (DNE) approach

4. Background – Solar Resources and a Solar Short-Term Forecast Anticipated rapid growth in larger solar facilities interconnecting to the transmission system requires development of tools that provide real-time situational awareness for system operators, as well as an accurate plant-specific short-term solar output forecast Solar monitoring and accurate forecasting requires nearly identical information as currently required from wind resources • Solar resources will also provide insolation data Development and calibration of an accurate solar forecast will allow solar resources to be dispatched under the DNE approach, along with wind and intermittent hydro resources • No target date has yet been determined for solar DNE Dispatch

5. What Changes are being proposed? The consolidation of wind and solar data requirements was initially discussed at the February 20, 2019 Transmission Committee meeting The new solar data requirements will be located in Market Rule 1 Wind data requirements will be relocated from the LGIA into Market Rule 1 • Deletion of the requirements from the LGIA will be reviewed in parallel by the NEPOOL Transmission Committee A new OP14 Appendix H (OP-14H) will be created later this year specifically for solar resources • OP-14H will be separately reviewed by the NEPOOL Reliability Committee • OP-14H will be similar to existing OP14 Appendix F for wind, which contains additional operational practices and recommendations. Examples include: • Ramp rate limitations • Recommended (not required) data collection points

6. Who Will be Affected? Most new solar facilities have already been voluntarily adhering to the proposed solar data requirements • By doing so, these facilities mitigate the need for upgrades and retrofits to take advantage of solar DNE Dispatch when implemented in the future All solar facilities that either participate in the New England markets, interconnect at the transmission level or through an ISO interconnection process, and are not Settlement Only Resources will need to meet the data requirements Solar facilities that do not participate in the New England markets and are not interconnected through an ISO interconnection process are not affected • In general, this means rooftop solar connected at the distribution level will not be affected

7. Final Note – Order 764 and LGIA Order 764 requires each public utility transmission provider to: “incorporate provisions into the pro forma Large Generator Interconnection Agreement requiring interconnection customers whose generating facilities are variable energy resources to provide meteorological and forced outage data to the public utility transmission provider for the purpose of power production forecasting.” ISO believes moving these requirements into MR-1 will • Achieve FERC’s intention of ensuring data requirements part of the ISO’s FERC-approved tariff • Avoid the need to replicate wind and solar data requirements in both the LGIA and the Small Generator Interconnection Agreements (SGIA) • Will address all of the solar facilities for which situational awareness is going to be important • Including those interconnected through a state interconnection process (i.e., not the LGIA or SGIA)

8. Conclusion • Solar and wind data requirements will be centralized in MR-1 • No change to wind requirements (other than tariff location), but extends tariff requirements to smaller facilities not covered by the LGIA • Solar requirements will replicate wind requirements very closely • Solar requirements expected to become effective in October 2019, upon Commission approval

9. Stakeholder Schedule

11. Acronyms Used in this Presentation DNE – Do Not Exceed FERC – Federal Energy Regulatory Commission LGIA – Large Generator Interconnection Agreement MR-1 – Market Rule 1 OP14 – ISO New England Operating Procedure No. 14; Technical Requirements for Generators, Demand Resources, Asset Related Demands and Alternative Technology Regulation Resources SGIA – Small Generator Interconnection Agreement