Variable Generation Subcommittee Planning Working Group

1. Variable Generation SubcommitteePlanning Working Group 11/16/09 Salt Lake City

2. Agenda • Welcome and Introductions • Anti-Trust Guidelines • VGS Charter • VGS Study • Activities of WestConnect, TSS, and SRWG- Ross Guttromson • Planning Issues for CA 33% RPS Studies – Ann Finley • Interface of TEPPC and VGS PWG – Scott Cauchois • Work Plan Activities and Recommended Changes • P1 Modeling - Bob Nelson • P2 IVGTF Mary Johannis • P3 Transmission Capacity for VG – Matt Muldoon • P4 Standard Planning Methods – Wally Gibson • P5 Transmission Adequacy – Ross Guttromson • P6 Centralized Data – George Nail • P7 System Dynamics – Steve Hill • Future Meetings • Adjourn

3. VGS Charter(Complete Document Online) • The VGS shall: • Ensure the members are aware of NERC activities related to renewable energy. • Participate, as requested, in pertinent NERC activities on behalf of the members. • Ensure the members are aware of NAESB activities related to renewable energy. • Participate, as requested, in pertinent NAESB activities on behalf of the members. • Solicit issues, analysis, and other information from members for the purpose of determining items of regional interest for planning, operations, and market interface. • Compile, on an ongoing basis, information on renewable energy integration and policy Issues in the Western Interconnection. • Provide for a central information portal (website) on renewable integration activities in the Western Interconnection. • Publish a quarterly newsletter of pertinent current events and VGS activities. • Provide regular updates to the JGC and members on VGS activities. • Develop specific WECC activities and actions for JGC consideration that will address regional reliability and market interface issues. • Coordinate VGS actions with other WECC committees, VGSs, work groups, as well as external groups that affect renewable integration in the Western Interconnection.

4. VGS Study • Two Phases- $500k and $1.5M ($2M Total) • Funding: WECC Grant, DOE/PNNL, DOE/NREL • Looks at entire US WECC (follow-on incl. Canada and Mexico) • Potential gains of sharing reserve with wind and solar • Share regular generation, wind, solar, load • With and without congestion • With and without Balancing Authority boundaries • Dynamic (asynchronous) schedules versus intra-hour (synchronous) schedules

5. Update on TSS and PCC • Spoke to Dana Cabbell (PCC Chair) and Kyle Kohne (TSS Chair) • Most coordianted efforts between PWG and PCC/TSS will fall to TSS, including heavy coordination on: • P3- Transmission Capacity for VG • P4- Standard Planning Methods • P5- Transmission Adequacy • PCC provides “stable” cases to TEPPC for their planning pursposes. Therefore, all cases they evaluate are viable from a stability point of view, but not necessarily an efficiency point of view. • We need to formally stay engaged with TSS- Ideas? Consider Creating a Planning Guide Book

6. Planning Issues for CAISO 33% RPS • New Calif. Independent System Operator (CAISO) Tariff Category – Renewable Transmission Projects • The California Energy Commission has an effort:  RETI - Renewable Energy Transmission Initiative.  • California Transmission Planning Group (CTPG):  Performing power flow and stability analysis of 2020 adjusted basecases to incorporate RETI conceptual transmission plan.    • CAISO’s 2010 Transmission Plan meeting held on Oct 26-27:  2020 renewable conceptual transmission

8. TEPPC and PWG Interface- Scott Cauchois • From Jamie Austin, chair of the Data Working Group: • .... the intra hour studies been deferred to VGS; then, the question becomes how can VGS deliver a response to these pending questions? • Although the TEPPC studies uses “hourly” time-step mimicking dispatch, the nodal models can also run with smaller increment time-step (intra hour) provided we have smaller increment data. As far as the practicality of running 10, 15 minutes increment time-step for a whole year, covering all seasons, for the entire western interconnect for the results to be useful, there are techniques that covers all that plus allows for reasonable run time (i.e., run intra-hour - use typical day, or typical week). • As for intra-hour data, NREL has it for wind as we all know and the WECC Regional Control Centers collect intra hour data for loads and other perimeters. So, the limiting factors are no longer models or data but becomes staff time to run the analysis, • From Tom Miller, chair of the Modeling work Group: • Hydro Modeling: Currently, we have implemented Hydro PLF/HTC,  which mimic the hydro system responsiveness to load and prices and helps to reconcile the coincidentail load/generation issue. While our modeling is for hourly dispatch it is also true for intra-hour dispatch. This is a significant improvement over the last study cycle. • Intermittent Resource Integration: assess needed operational flexibility requirements in power system planning: my wish is that we perform some analysis using the tool PG&E has developed that helps estimated the incremental need for additional regulation/load following and capacity back-up for different user defined renewable portfolios at different pentration levels. This model is able to mimic  load and renewable forecast errors using 5 minute data. If we focused the analysis on regions of high renewable development we could get a reasonable estimate of the system needs and have a good way to bracket the costs of integration commensurate with the study scenarios. In addition this type of analysis could provide further insight into the change in system ramp rate requirements during morning and evening heavy ramp periods and the diverity benefits of regional wide renewable development. Doing a full year intra-hour production simulation using promod would not be practical. • System Operational Flexibility Assessment: wish two:  I believe decision makers are very concerned over system operational impacts associated with the policies being explored.  A valuable product would be to quantify the system operational flexibility/capability on a regioanl basis as a function of increasing non-dispactable resources (e.f. EE, DG, renewable..), reliance on limited resources such as demand response and retirement of a large stack of OTC units. • So, from the VGS group working on data inputs for the integarion tool and helping to perform the analysis would be excellent. 

9. PWG Work Plan Buy-Off • Does the Activity Make Sense? • If Not, Propose Changes and Vote • If Yes, Provide Status Report • P1 (Modeling) Antonio Alvarez, Bob Nelson, Steve Hill • P2 (IVGTF) Antonio Alvarez,MaryJohannis,  Bob Nelson, Michelle Mizumori, Michael Milligan • P3 (Transmission Capacity for VG) Matt Muldoon • P4 (Standard planning methods) Wally Gibson, George Nail, Antonio Alvarez, Mary Johannis • P5 (What transmission adequacy analysis is needed) Ross Guttromson, Wally Gibson • P6 (Centralize Variable Generation Data) George Nail, Mohan Kondragunta, Heidi Pacini, Michael Milligan • P7 (System Dynamics Issues) Mohan Kondragunta, Steve Hill, Ann Finley

10. P1. Participate in Industry Efforts on VG Modeling (Bob Nelson) • I think we need to be concerned with transient modeling (EMTP, PSCAD, etc.) as much as dynamic modeling.  • Also, some of the new inverter-based equipment have different short-circuit and steady-state characteristics than conventional synchronous machines.  But the available short circuit and load flow models in the existing power system software packages (PSLF and PSS/E) remain those of synchronous machines.  I think these characteristics should be addressed properly by the software models. Users should not have to provide a subtransient reactance, for example, for a full-converter wind turbine or PV generator.

11. P2. Review NERC IVGTF Report (Mary Johannis) • I have reviewed the work plan and tasks regarding coordination with the NERC IVGTF and believe they are appropriate.  • Below is a link to the April 2009 IVGTF Report, Accommodating High Levels of Variable Generation.  Appendix I, starting on page 68 contains the work plan proposed by the IVGTF to the PC in order to address issues identified in the report.  The PC approved these implementation actions at their June 2009 meeting and set up teams to follow through with the work plan.  • http://www.nerc.com/docs/pc/ivgtf/IVGTF_Report_041609.pdf • Two of the tasks, which are pertinent to the VGS PWG, are being implemented by joint IVGTF - RIS (Resources Issues Subcommittee) teams.  These tasks are: • Task 1.2: Consistent and accurate methods are needed to calculate capacity values attributable to variable generation. • Task 1.4: Resource adequacy and transmission planning approaches must consider needed system flexibility to accommodate the characteristics of variable resources as part of bulk power system design. • I, along with other VGS PWG members, am participating on these teams.  Attached is the most recent thinking in terms of deliverables from these teams.  Both deliverables are in the form of reports back to the NERC PC.  Monday's meeting presents an opportunity to discuss the VGS PWG's throughts on these report outlines.  Also, if anyone wishes to volunteer to provide input to the report(s)--that would be much appreciated.

12. P3. Transmission Capacity Assignment (Matt Muldoon) • 1) Increasing transmission capacity for managing variability across • Europe: (See chapters 5 and 6 in particular) http://www.trade-wind.eu/fileadmin/documents/publications/Final_Report.p • df • 2) Review of balancing costs, transmission upgrades, and capacity credit for wind across numerous country by country studies: • http://www.vtt.fi/inf/pdf/tiedotteet/2009/T2493.pdf • 3) Policy level review of the costs of intermittency, including capacity credit calculations (doesn't include much in the way of transmission) http://www.ukerc.ac.uk/Downloads/PDF/06/0604Intermittency/0604Intermitte • ncyReport.pdf • (Box 2.7 discusses the ways to measure reliability and short-comings of the LOLP method) • 4) Evaluation of different methods used for calculating the capacity credit of PV (attached) • Hoff, Tom, Richard Perez, JP Ross, and Mike Taylor. 2008. Photovoltaic Capacity Valuation Methods. Washington D.C. : Solar Electric Power Association, May. • http://www.solarelectricpower.org/docs/PV%20CAPACITY%20REPORT.pdf. • 5) Evaluation of the economics of downsizing transmission capacity relative to the nameplate capacity of wind, plus the question of is storage more economic if sited at the load center or sited at the wind region (attached) • Denholm, Paul, and RamteenSioshansi. 2009. The value of compressed air energy storage with wind in transmission-constrained electric power systems. Energy Policy 37, no. 8 (August): 3149-3158. • doi:10.1016/j.enpol.2009.04.002. • 6) The economics of tidal energy (including an estimation of the capacity credit of tidal power) (attached) • Denny, Eleanor. 2009. The economics of tidal energy. Energy Policy 37, no. 5 (Ma

13. P4. Standardizing and Validating Planning Criteria and Methodologies (Wally Gibson) • To Discuss

14. P5. Perform Transmission Adequacy Analysis for Accomodating the Integration of VG (Ross Guttromson • I recommend that P3 (capacity) and P5 (adequacy) should be combined into a single task. • Currently, TEPPC receives cases from TSS that have sufficient transmission and are dynamically stable. Adequacy would only be in question if the transmission capacity were reduced to allow for statistical variations in variable generation (e.g. seasonal, vocational, capacity factor)

15. P6. Create Centralized Database on VG Information (George Nail) • Change To: • This is a specific, measurable, task that supports the objective. • Overall start • Overall finish • Work with LRS committee and request hourly VGS generation along with intra-hour variability defined as the standard deviation of 6 - 10 minute measurements reported hourly in the 2009 Actual year data request (to the extent that 10 minute data is available.) Actual year data request for all Wind and Solar resources. LRS meeting 11/20/09 • 11/16/2009 • 3/1/2010 • Review 2009 Actual Year data request submission for completeness and refine request process for 2010. Submit data for task 3 below. • 3/1/2010 • 11/1/2010 • Help L&R Subcommittee compile VG data and incorporate the information into a database that will be made available to VGS workgroups and WECC members. • 03/1/2010 • 6/30/2011

16. P7. System Dynamics Issues • I recommend that this task be terminated. • PWG already has dynamics issues addressed in P1 • Note, that TSS has responsibility for system dynamics. • PWG role would be to aid TSS