1. Alaska Wind Integration Conference June 29, 2010 Oahu Wind Integration Study Dean Arakawa Sr. Engineer, Renewable Energy Planning Hawaiian Electric Company

2. 2 The Challenge

3. 3 Hawaii’s Economy in 2008 SPENDING ON ENERGY $ 8.4 BILLION GROSS STATE PRODUCT$63.8 BILLION

4. 4 Hawaii’s Energy Use Today Primary energy: 90% fossil fuel, Imported crude oil refined: ELECTRICITY 32% JET FUEL 34% GASOLINE/ 27% MARINE FUEL OTHER7%

5. 5 Hawaii’s Electricity Issues are Fundamentally Different than the Mainland US

6. 6 The Solutions

7. 7 A Paradigm Shift is Required Economic drain>Economic engine Energy insecurity>Energy security Environmental harm>Environmental compatibility Price volatility>Price stability

8. 8 Where Are We Today? As of 2009 – Hawaiian Electric companies 19 % Renewable Energy & Energy Efficiency (~50% / 50%) State Goal by 2030 – for Hawaii’s economy 40% Renewable Energy 30% Energy Efficiency

9. 9 How We Can Move Ahead: Grid transformation Renewable energy including liquid fuels substitute Inter-island connection

10. 10 Kauai Oahu Molokai Lanai Maui Hawaii Oahu’s Challenge Solar Wind Geothermal MSW Biomass/ Biofuel OTEC/ Wave DSM/Energy Efficiency Population 905,601 * Population 173,057 * Tri-island population 141,783 * * U.S. Census estimates as of July 2007

11. 11 Hawaii’s Wind Energy Resources

12. 12 Wind on Molokai and Lanai 9/3/2015

13. 13 Renewable Game Plan for Hawaii  The load is on Oahu, but the renewable resource is limited.  The neighbor islands have abundant renewable resources, but limited load. Ultimately, the islands can benefit by being cabled together.

14. 14 How Can We Do It? ‘Interisland Wind’ Lanai & Molokai wind farms – 200 MW each – Undersea cable to Oahu Learn more at: www.interislandwind.com

15. 15 HECO’s System

16. 16 Hawaiian Electric ISLANDPEAK DEMAND (2008) OAHU*1200 MW MAUI 195 MW HAWAII 200 MW KAUAIserved by separate utility co-op * 80% of state population Isolated, stand-alone grids

17. 17 Big Wind Components Successful Big Wind Wind Plant Development & Performance = Required wind plant forecasting and performance characteristics Resource intermittency mitigation and management (e.g. energy storage requirements) Adequate capacity factor yielding commercially reasonable pricing Community acceptance of large wind plants Wind Plant Issues Undersea Cable Intertie + Sizing and selection (AC, DC) Cable system reliability and configuration (e.g. mono-pole, bi-pole, spare cable, etc.) Landing sites and footprint for converter station and supporting equipment Ocean permitting and environmental issues O&M responsibilities and operating agreement Cable Issues Oahu Integration & Infrastructure + Oahu Issues Maintain 60Hz frequency and system stability Maintain adequate operating reserves in response to wind Improve generator response Enhance system controls and automated features Maintain reliable operations via PPA commitments Community acceptance of new T&D infrastructure

18. 18 Generation Resources on Oahu H-POWER (46 MW) H-POWER (27 MW) Waiau (473 MW) Honolulu (108 MW) Kahe (604 MW) AES (180 MW) Kalaeloa (208 MW) Legend Firm Capacity, Net-MW CIP CT-1 (113 MW) Future As-Available Resource, MW-nameplate Kahuku Wind Power (30 MW) Honua Power (6 MW) Future Firm Capacity, Net-MW Airport DSG (8 MW) Total Existing Firm Capacity = 1,732 MW-net Total Future Firm Capacity = 35 MW-net Oahu RE RFP Pending 400 MW Wind Planned

19. 19 Inter-island Wind Project Scenario Analysis (GE MAPS/PSLF) HECO Baseline Information HECO Model Development GE Wind Forecasting Oahu Transmission Studies Stead State Load Flow/ Transient Stability/ Short Circuit Steam Generator Improvements Load Control Standby/Quick Start Generation EMS/AGC Capability Analysis Oahu T&D Routing Study and Engineering Design Submarine Cable Architecture and Functional Specs Wind Resource Modeling PPA Negotiations/ Interconnection Requirements Study Wind Capacity Calculation Steam Generator Projects EMS Upgrade Projects Load Control Projects Future Generating Resource Plan Oahu Transmission Projects Submarine Cable Procurement and Permitting Follow-on Implementation

20. 20 Oahu 600MW of new Renewables ~1200MW Peak Lanai +200MW new Wind sub- sea cables Molokai +200MW new Wind +100MW new Wind +100MW new PV Scenario Analysis These 3 scenarios were analyzed to determine the commitment/dispatch, identify new operating characteristics, and establish a new baseline to assess strategies to enhance operation with high penetrations of renewables These four scenarios were the focus of the study (Scenarios 2 and 4 were only moderately different than these three scenarios). Interest from the team to focus effort on mitigating strategies as opposed to these only moderately

21. 21 New tools and data needed to properly model and assess system impacts within operational time constraints. Tools Needed For Each Timescale

22. 22 Modeling Tools

23. 23 Wind and Solar Data Development Wind and solar data monitoring units Develop high resolution wind and solar time series data for modeling work

24. 24 Model Data Requirements Summary of Thermal Unit

25. 25 Wind energy curtailment at high penetrations Zero marginal cost energy not being accepted More frequent operation of thermal units at minimum power What if there is a loss of load on the system? Large system contingencies What if the undersea cable trips? Variability of wind energy Large sustained drops in wind/solar power during load rises Reduced thermal unit efficiency & potentially higher O&M costs Higher sub-hourly maneuvering to balance wind/solar power Integration Challenges …

26. 26 Wind power forecasting to improve unit commitment Refine up reserve requirements based on wind power variability Reduce minimum power of baseload units Seasonally cycle-off select baseload units Reduce reserve requirement (use of fast-start units and load control) Increase thermal unit ramp rate capability Consider advanced wind turbine technologies to provide “grid support” (e.g., inertia, over-frequency control) Evaluating Candidate Strategies

27. 27 Dynamic Response Study Improving the dynamic responses of generating units on the HECO grid will facilitate the interconnection of greater amounts of variable generation with reduced amounts of other technologies to mitigate adverse operational impacts. PREMISE

28. 28 Objectives 1.Confirm I&C logic for “AGC” of governors 2.Characterize existing inertial, droop, and AGC (i.e., “ramp rate”) responses 3.Develop control strategies and tune systems for improved response (model input) 4.Identify factors and equipment that limit unit response 5.Identify capital projects to address limitations

29. 29 Pre-Tuning Uninhibited Boiler Following Response Trend Combustion Control at Top Load

30. 30 Post-Tuning Uninhibited Boiler Following Response Trend

31. 31 Post-Tuning 3 MW/min Coordinated Control Response Trend

32. 32 5 MW/min Response Trend

33. 33 System Load/Frequency Response to 125 MW Kahe 5 Trip (3-14-2009, 20 min response)Theo W. Hetherington – C.S.Squared

34. 34 DYNAMIC RESPONSE – GENERATING UNITS For Analytical Purposes Only Projected Droop UnitODOM"Everyday""Once-in-While"(governor) (MW/min) (%) H81.43.05.0 H91.43.05.0 W30.92.54.05.0 W40.52.54.05.0 W51.43.05.0 W61.43.05.0 W72.35.07.05.0 W82.35.07.05.0 W93.05.010.05.0 W103.05.010.05.0 K12.35.07.05.0 K22.35.07.05.0 K32.35.07.05.0 K42.35.07.05.0 K52.57.010.05.0 K62.56.08.05.0 CIP CT-1na10.013.05.0 H-Power2.01.82.05.0 KPLP2.55.0 AES2.55.0

35. 35 Impact of Renewables Variability on System Frequency Higher thermal unit ramp rates helped manage frequency Large and fast-wind power variability over the 5-10min timeframe in both directions Largest wind forecast error. Largest hourly wind drop (311MW; 27% of gen.) All fast-start units dispatched Fast Wind Power Variability Aug 30 th 10am (995MW Load) Sustained Wind Power Drop Oct 12 th 2pm (1160MW Load) Manageable system frequency over fast wind variability events Manageable system frequency over largest wind drop GE Internal – HECO Proprietary

36. 36 200MW Lanai (curve on top of one another) Thermal Unit Ramp Rates & Droop Today’s Ramp Rate / Droop Propose Future Ramp Rate / Droop UFLS at 59.5 Hz Large Wind/Solar/Load Change Aug 30 th 10am (1108MW Load)

37. 37 Results

38. 38 Operational Strategies and Unit Modifications More Wind Energy Delivered & Lower Variable Cost Benefits from… Operational Strategies  Wind forecasting & refine up reserve requirement Thermal Unit Modifications  Reduce unit min power & seasonally cycle off baseload units Modifying Reserve Req’ts  Credit load control & fast-start units for up reserve

39. 39 What Worked Well for HECO Dedicated cross-functional team Technical Review Committee Weekly meetings during scenario analysis Selected the most difficult scenario first Prudent use of modeling results

40. 40 Hawaii’s Energy Future www.hawaiisenergyfuture.com Hawaiian Electric Company www.heco.com Hawaii Clean Energy Initiative http:/hawaii.gov/gov/initiatives/2009/energy http:/hawaii.gov/gov/initiatives/2009/energy Hawaii energy data http://hawaii.gov/dbedt/info/energy Thank You Learn more ….

41. 41 BACK UP

42. 42 Oahu Generating Fleet

43. 43 How is frequency performance affected by installed wind power and scenario assumptions? No solar variability, No AES governor response PSLF Input Data Good correlation between increased wind power variability and associated frequency performance 3B and 5B scenarios have better frequency performance than 3F3 and 5F3 scenarios. This is because fewer units are against their limits (more up regulation in 3B and 5B as compared to 3F3 and 5F3). Proposed Ramp Rates & DroopsWind Power Variability

44. 44 How much does maneuvering of HECO units increase in scenarios with more wind power? Maneuvering of HECO units doubled in scenarios with offshore wind for slow and fast variations Proposed AGC ramp-rates, no solar variability, no AES governor response A high percentage of total system variability (>80%) is counteracted by HECO units in all scenarios and for fast and slow variations. System variability is higher if solar variability is considered. HECO units perform most of the maneuvering.

45. 45 What units increase maneuvering in scenarios with more wind power? Variability of HECO units increased to counteract additional wind power variability in scenarios 3 and 5 Proposed AGC ramp-rates, no solar variability, no AES governor response PSLF