Integrated Capacity Analysis Working Group January 6, 2017 In-person meeting drpwg.org

Agenda Time Topic 9:00-9:15 9:15 - 10:00 10:00 – 11:00 11:00 – 12:00 Introduction, Overview of January Calendar, Purpose of WG Report 9:15 - 10:00 B. IOU presentations on final demo results 10:00 – 11:00 Q&A session with IOUs and WG members on results 11:00 – 12:00 D. WG recommendations and report drafting process 12:00 E. Next Steps and Lunch

ICA and LNBA Working Group Background ICA and LNBA WG Purpose - Pursuant to the May 2, 2016, Assigned Commissioner’s Ruling (ACR) in DRP proceeding (R.14-08-013), the Joint Utilities are required to convene the ICA and LNBA WG to: Refine ICA and LNBA Methodologies and Requirements Authorize Demonstration Project A and Project B CPUC Energy Division role Oversight to ensure balance and achievement of State objective (ensure adequate stakeholder representation in consensus statements, keeping WG activities on track with Commission expectations/needs, demonstration project results review, quality control on deliverables) Coordination with both related CPUC activities and activities in other agencies (IDER CSF WG, CEC and CAISO interagency matters, interconnection/Rule 21/SIWG, other proceedings that may impact or be impacted by locational value calculation such as AB 350/IRP and LTPP/TPP/RPS) Steward WG agreements into CPUC decisions when necessary More Than Smart role Engaged by Joint Utilities to facilitate both the ICA & LBNA working groups. This leverages the previous work of MTS facilitating stakeholder discussions on ICA and LBNA topics.

CPUC Decision Points for ICA/LNBA Working Group Short-Term Final Reports ICA/LNBA Working Group January 6, 2017 Oakland, CA

Proposed Decision on Demo A&B will need to address: Compliance with May 2, 2016 ACR (and February 6, 2015 Guidance Document) ICA/LNBA Use Cases WG-recommended methodological adjustments needed to achieve Use Cases Based on prescribed Demo methodologies and Short- Term refinements Implementation requirements/schedule

Consensus Process Proposal for Discussion For each topic, the WG will characterize its recommendation as: 1. General or majority consensus (by a show of hands or absence of objecting voices) 2. Non-consensus, with alternative proposals For non-consensus positions, MTS will identify the number of parties and list party’s attribution and proposed alternative in the report A comment period after the final report is filed is considered for parties to submit final comments. MTS will work with WG members to develop text for the report. For certain sections, the WG may assign a chair and co-chair lead to coordinate development of text.

Update on Timelines Date Short Term Long Term Jan. 6 In-person meeting Determine schedule for discussions up to Q2 2017 Begin LT refinement discussions Jan. 11 First draft circulated Jan. 17 First round of edits due Jan. 18-19 Second draft circulated Jan. 20 Webinar Jan. 27 Second and final round of edits due Jan. 31 Report submitted For consideration: Extend first round of writing to Jan. 12/13?

Integration Capacity Analysis (ICA) – Working Group IOU Demo A Findings Overview January 6, 2017

Purpose and Overview Provide the ICA Working Group an overview of the Demo A finding with overview of the ICA Roadmap Demonstration Project A Summary (15 Minutes) Distribution Planning Areas (DPAs) Integration Capacity Analysis (ICA) Methodologies Overview of the Results Comparative Assessment between ICA Methodologies Mapping and Publication Overview Additional Studies Challenges and Lessons Learned (15 Minutes) Modeling and Simulation of Power Systems Software, Script Development, and Computational Performance Mapping and Publication ICA Roadmap (15 Minutes) SCE System Short- and Long-Term Enhancements

Distribution Planning Areas (DPAs) Southern California Edison Pacific Gas & Electric San Diego Gas & Electric Distribution Planning Area Rector DPA (Rural) Johanna DPA (Urban, Suburban) Demo A DPA Chowchilla DPA Chico DPA Ramona DPA Northeast DPA Substations 5 4 9 10 14 19 24 Feeders 44 38 82 20 41 61 137 156 Loading (MW) 314 217 531 155 235 370 65 815 880 Number of Customers 49,700 25,100 74,800 13,000 125,000 138,000 20,538 204,985 225,523 Nodes 12,442 4,687 17,129 12,914 22,898 35,812* 40,459 228,049 268,643 In the selection of the DPAs, the IOUs considered characteristics such as average feeder length, average electrical resistance, feeder loading levels, customer diversity, and installed distribution equipment * PG&E’s new GIS models in development have 20% more nodes for the demo A area due to enhanced geospatial accuracy using new GIS system.

Integration Capacity Analysis (ICA) Methodologies Alignment Streamline Method Iterative Method Limits Southern California Edison Pacific Gas & Electric San Diego Gas & Electric Thermal Equipment Thermal Rating X Steady State Voltage Over or Under Voltage Voltage Fluctuation Change in Voltage of 3% Protection Relay reduction of reach Safety Reliability No reverse on SCADA devices

General Demo Result Trends

Demo Example Results by Distance Typical Urban Results Typical Results (Mixed chart) Typical Rural Results

ICA Methodologies – Comparative Assessment Iterative ICA methodology more accurate in determining power flow impacts, but more difficult to determine hosting capacity; issues often arise with with simulation convergence. Streamlined ICA Methodology is significantly faster, but may lack ability to determine specific complex operational issues On average, the SCE Iterative and Streamlined ICA results differed between 18% to 30% on a node to node basis.* SCE Demo A Results Overview – Average hosting capacity ranges. At a high level, Streamlined and Iterative ICA Methodologies align on results. The difference is apparent when node-to-node comparisons are established though, with difference ranging between 18% to 30% * PG&E’s iterative results created many non-convergent and/or zero results that were not reasonable to evaluate across entire demo area for report

Mapping and Data Sharing Southern California Edison Pacific Gas & Electric San Diego Gas & Electric Map http://on.sce.com/derim Will provide on publication https://sempra.maps.arcgis.com/ Attributes Circuit Section ID Voltage (kV) Substation System Customer Breakdown % (Ag, Comm, Ind, Res, Other) Existing Generation (MW) Queued Generation (MW) Total Generation (MW) Integration Capacity, Uniform Generation (MW) Integration Capacity, Uniform Load (MW) Integration Capacity, Typical PV System (MW) All map content can be downloaded via ESRI Open Data same

Mapping and Data Sharing Southern California Edison Pacific Gas & Electric San Diego Gas & Electric Load Profiles http://on.sce.com/derimwebapp Attributes Typical high-load day (288 data points) Typical light-load day (288 data points) Interactive. Hover over to obtain x/y coordinates. same

Mapping and Data Sharing Southern California Edison Pacific Gas & Electric San Diego Gas & Electric Downloadable Data http://on.sce.com/drpdemos Will provide on publication Files Available Demo A Final Report ICA Translator Load Profiles Customer Type Breakdown Detailed ICA Results by Circuit Additional Resources http://on.sce.com/derimguide TBD

Computation Summary Southern California Edison* Pacific Gas & Electric San Diego Gas & Electric Average Run Time per Feeder (Streamlined Method) 2 minutes 7 minutes 30 minutes Average Run Time per Feeder (Iterative Method) 23 minutes 83 minutes 1,620 minutes Data Size 6.66GB ~100GB 4.79GB * SCE’s run time statistics reflect limitation category and hourly reduction measures, but does not account for data processing. 

Lessons Learned and Challenges – Electric System Modeling Nodal granularity requires precise models and possibly manual editing 1. Load, DER, connectivity, and equipment sometimes requires manual intervention 2. SCADA and AMI must be reconciled 3. Unknown phasing can limit model accuracy Nodal/hourly simulation requires rigorous processing 1. Feeder length & complexity increase number of iterations 2. VAr supply and/or equipment settings can lead to non-convergence of simulations 3. Error tolerance in load allocation and power flow solution may need to be increased 4. Common bus solution leads to longer processing and more non-convergence of simulations Such complex results are difficult to validate 1. Large volume of data is difficult to manually validate 2. Zero ICA may result from unexpected or indirect electrical conditions 3. Expected result validation requires tedious manual simulation (spot checks)

Lessons Learned – Computational Challenges Development of scripts Translating theory to practice is an iterative method requiring extensive knowledge of engineering and computer science principles Must be coordinated with software vendors and relies on incremental software updates to ensure proper functionality for complex analysis. Long Runtime Required Computational time required for each methodology is exacerbated by the amount of feeders, feeder complexity, method used, and simulated hours. Scalability of Systems Scripts, databases, and processing capabilities need to be scaled up to handle periodic ICA updates of the entire distribution system Data Management and Quality Assurance The ICA data structures need to progress into more robust enterprise friendly databases Results Validation Volume of results makes it increasingly difficult to validate data Expected vs obtained results based on manual simulation (spot checks) ICA Process Due to complexities in process, from data gathering and modeling to simulation and publication, automated end-to-end process will be required to meet goal of analyzing the entirety of distribution system

Lessons Learned – Publication Challenges Granular nodal/hourly result set is too big for current map publication interface. Reduction of data to be published and/or different data interface (i.e. Azure cloud) could alleviate concerns. IOUs would like to limit future downloadable data to only the most actionable data going forward that can practicably be applied towards current operational framework. Alternative solutions to publishing interactive load profiles should be explored as well. The web map applications are not the ideal platform for publishing non-geospatial time based load profiles. Current mapping platforms are expected to be sufficient for node results, but full testing has not been conducted. SCE has identified an investment in the Distribution Resource Plan External Portal (DRPEP, 2018 GRC) that would greatly enhance the user experience. PG&E currently has no specific funding for a new DRP data portal SDG&E currently has no specific funding for a new DRP data portal, but has made some modifications to existing portal for Demo A

ICA Roadmap Proposal to perform final ICA implementation within 12 months following final resolution from the PUC. IOUs to evaluate the resource requirements to further enhance the efficiency and scalability of full ICA deployment. SCE has identified a number of investments in its 2018 GRC (SMT, DRPEP, LTPT, and GAA) that will continue to enhance overall ICA efficiency and customer experience.

Southern California Edison San Diego Gas & Electric Recommendations Activity from Ruling Southern California Edison Pacific Gas & Electric San Diego Gas & Electric 3.1.a Update schedule for Demo A results N/A 3.1.b Recommend methods for evaluation of hosting capacity for the following resource types: i) DER bundles or portfolios, responding to CAISO dispatch; ii) facilities using smart inverters IOUs should continue to use tech agnostic approach for 2017 implementation. IOUs should not be required to make assumptions about CAISO dispatch or other specific resource types.  same IOUs should continue to study smart inverters with the WG, but should not be required to incorporate smart inverters in the 2017 implementation. Same IOUs should provide uniform inverter gen and uniform load, as was done with Demo A. 3.1.c Recommend a format for the ICA maps to be consistent and readable to all California stakeholders across the utilities’ service territories with similar data and visual aspects (color coding, mapping tools, etc.) IOUs should work with the WG to implement minor modifications to the maps and data sets. IOUs should not be required or expected to implement major revisions for the 2017 implementation. 3.1.d Evaluate and recommend new methods that may improve the computational efficiency of the ICA tools and process in order to calculate and update ICA values across all circuits in each utility’s service territory in updated ICAs more frequently and accurately IOUs should continue to improve efficiency where possible. The approach in Demo is acceptable for system-wide implementation. (see p. 76 of SCE report) IOUs should continue to improve efficiency where possible. PG&E supports streamlined for system-wide analysis and finds iterative not to be feasible for full system analysis  IOUs should continue to improve efficiency where possible. The approach used by SDG&E in Demo is acceptable for system-wide implementation, but is infeasible for frequent updates. 3.1.e Evaluate ORA's recommendation to require establishment of reference circuits and reference use cases for comparative analyses of Demo Project A results Additional use of reference circuits is not necessary but SCE is acceptable to explore additional reference circuits. A more complex reference circuit than the IEEE 123 test feeder will be helpful, but reference set should be limited to a single circuit due to complexities of comparison as observed in Demo A  While reference circuits can be valuable, they will require work that will take away from system wide implementation 3.1.f Establish a method for use of Smart Meter and other customer load data to develop more localized load shapes to the extent that is not currently being done The approach used in the Demos is appropriate for System wide implementation with increased utilization of smart meter data based on technology advances to remove to remove obstacles observed in Demo A.   The approach used in the Demos is appropriate for System wide implementation  The approach used in the Demos is appropriate for System wide implementation 3.1.g Establish definite timelines for future achievement of ICA milestones including frequency and process of ICA updates IOUs should update ICA on a monthly basis following the initial system-wide implementation, if possible given computing resources. Initial system wide deployment should allow 12 months from PUC final ruling ICA should be updated no faster than on a monthly basis following the initial system-wide implementation. Initial system wide deployment should allow 12 months from PUC final ruling  updates should be done on a semi-annual basis for interconnection purposes. Scenario analysis can be performed annually.

Southern California Edison San Diego Gas & Electric Other Recommendation Southern California Edison Pacific Gas & Electric San Diego Gas & Electric Overall Methodology ·       recommend a blended approach with adequate levels of iterative power flow method and streamline method ·       Recommend a blended approach using iterative and streamlined method where deemed appropriate due to use case and practicability SDG&E recommends a blended approach with iterative power flow method used for interconnection, and the streamline method used for planning ·        For Interconnection use case iterative method is recommended. This information is what would be used for ICA maps  ·        Iterative method is recommended for Interconnection use case . PG&E did not find iterative feasible for full distribution analysis and nodal mapping and thus should be limited to interconnection process. For Interconnection use case iterative method is recommended. This information is what would be used for ICA maps ·        For other use cases such as Planning or scenario analysis, the streamline method is recommended ·        Streamlined method is recommended for Planning use case in which full nodal and system wide analysis can be performed efficiently. For other use cases such as Planning or scenario analysis, the streamline method is recommended Timing of initial system-wide implementation ·        IOUs should be given at least 12 months to perform initial system-wide implementation, assuming above recommendations are adopted. Additional requirements may require additional time for completing ICA  same Single phase feeders ·        IOUS should continue to study potential expansion to single phase feeders. IOUs should not be required to include single phase feeders in the 2017 implementation Same Long-term refinements ·        Long-term refinements being discussed in the working group. The Q1 Decision should not address long-term refinements.

WG Report Recommendations: Proposed Outline Executive Summary Evaluation of Results Key Takeaways: ORA 12 Success Criteria Use cases Other? Methodology ICA Implementation Requirements and Time Frame (timing/frequency of updates) Implementation schedule and requirements Initial implementation deployment Use Cases Further long term refinements Methodology Recommendations B. Evaluation for 1) DER bundles or portfolios and 2) facilities using smart inverters Others? C. Map format D. Computational efficiency E. Comparative analyses/reference circuits Response to recommendations by IOUs of use of iterative/streamlined approaches F. Method for smart meters and localized load shapes

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