1. Integration of Large-Scale RES in Island Power Systems Prof. Nikos Hatziargyriou, National Technical University of Athens nh@power.ece.ntua.gr

2. Outline  RES in Greek Islands  The Power System of Crete  Smart Grids for the Greek Islands  More Care Energy Management System  Microgrids  The Kythnos Experiment

3. Power Stations on Greek Non Interconnected Islands 3 6 Thermal Stations Total installed capacity MW 1.780 Capacity of new thermal units ( 2011 – 2015 ) 392 963 RES Stations 80 Wind Farms 883 PVs 330 2 65 70 Capacity of new RES stations ( 2011 – 2015) Wind Farms PVs Hybrid Stations CSP Stations 415 175 130 70 40

4. RES Production per system in 2010 470 480 15,8 % 7,4 % 10,1 % 13,9 % 8,5 % 8,2% 11,4 % 4,6 % 3,4 %9,8 % 7,9 %13,5 % 0,9 % 13,6 %

5. Average Variable Cost per system (2010) Very Small IslandsNew Power Stations & and Large islands SMP AVC Mykonos Crete

6. Significant increase of RES installation in Greek islands based on new technologies Power Stations Hybrid Power Stations with Wind Farms, pump-storage systems and Hydroelectric Power Stations Nominal capacity from 2 MW up to 75 MW Concentrated Solar Power (CSP) Stations with storage systems of thermal energy from 4h up to 8h Nominal capacity from 25 MW up to 70 MW Hybrid Power Stations with battery systems and Wind Farms or Sterling Generator.

7. Total RES installed capacity and production in Greek Non Interconnected Islands for 2003-2020 12,1% 28,2% 40 % 2015(MW) W/F428 PV190 HPS50 CSP35 2018(MW) W/F517 PV220 HPS153 CSP105

8. Power system of Crete

9. Crete – Operational Characteristics Largest Island System in Greece with highest rate of energy and demand increase. Three thermal power plants, installed cap. 800 MW.  Base-load mainly supplied by steam and diesel units.  Combustion turbine units normally supply daily peak load at high running cost.  26 Wind farms of total Capacity 166 MW. Most of Wind Farms installed at the eastern part of the island.  PVs 60 MW No. of Machines Nominal Power (MW) Linoperamata Steam6110 Diesel448 Gas5120 Chania Gas6198 CC1+2132 Atherinolakos Steam Diesel 2222 100 102

10. EES-UETP “Planning, Designing and Operating the Distribution Network for Exploitation of DER”, Cagliari, 27-30/9/04

13. Wind Park in Crete

14. Load and Wind Farm production in Crete system during the year 2010 640MW 170MW =3.7

15. Rokas W/F output (13 May 1998)

16. Rokas W/F output ( 20 May 1998 )

17. HPS WF (28.9/11.9 MW) HPS 5MW HPS 5.1MW HPS WF (39.95/9.35 MW) HPS 75 MW HPS 5.1 MW Hybrid 9MW Development of Hybrid Power Stations with pumping systems and CSP Power Stations in Crete up to 2018 HPS 12MW CSP 25MW CSP 70MW HPS 1.95MW HPS 12MW HPS 9MW HPS 15MW HPS 1.95MW CSP 50MW POWER STATION TYPE (total capacity)STATIONSNOMINAL CAPACITY Hybrid Power Station (151,1 MW)12 – 75 MW Concentrated Solar Power (243 MW)525 – 70 MW CSP 38MW CSP 60MW

18. System Operation (27/6/2011) (PV ~35MW) Expensive unit used Technical minimum problem High RES penetration (>30%)

19. Increased WF penetration PV production is estimated. RES penetration>50%

20. Wind Production the day of year’s load peak (Aug.12.1999)

21. Voltage and frequency  Operating frequency bandwidth: 49,9 - 50,1 Hz (Normal mode) 49,3 - 50,5 Hz (Contingency mode)  Operating voltage bandwidth: + 3,5 %  Typical power reserve margins: 10% (spinning)

22. Operational problems  Technical limits of thermal base-load plant during valleys of load demand  Narrow tolerances of wind generators to voltage and frequency deviations  Loss of wind generation following incidents of system faults or system transients

23. Operational problems (continued)  Wind availability, and short-term wind variations (gusts) – the latter resulting in substantial power swings in wind generation outputs  Communication problems between the system Control Center and the Wind farms  Miscellaneous, such as: wind-generator maintenance and repairs, distribution line problems, etc

24. MORE CARE

25. Major functionalities of MORE CARE  Forecasting Modules  Unit Commitment/Economic Dispatch  RES/Storage Management  Optimal Power Flow  Security Monitoring/Assessment

26. The CARE System Architecture

27. Flow- chart

28. MMI of More Care System

29. MMI for Wind Forecast

30. Load & Wind Forecasting  Modern Systems Provide Advanced Capabilities  For Wind Power forecasting:  ICCS participates in innovative projects: Anemos.plus and SafeWind  The information includes confidence intervals and extreme events Advanced Modules Meteo Forecast

31. Unit Commitment /Economic Dispatch The Unit Commitment problem becomes very complex:  Market Rules and Existing Contracts  RES Management  Future Storage Management  Ancillary Services according to market rules  Technical Constraints and Reserve Management

32. Unit Commitment /Economic Dispatch  Advanced functionalities to provide advice to the operators Advanced Modules Simple Messages to the operator

33. Security Monitoring/Assessment  Operation of islands becomes very complex  It is very demanding for the operator to consider power flow constraints or dynamic response of generators  Early Warning to the operators in case of security concerns is necessary – AI techniques Dynamic Monitoring & OPF

34. Simulation of 23 MW Gas Turbine Outage Case 1. Load of 207.2 MW, Wind Power 69 MW, 33.3% penetration Case 2. Load of 199 MW, Wind Power 55.73 MW, 28% penetration

35. Historical Data Management  Online History Access

36. Statistics and Reporting

37. Conclusions  Increased RES penetration complicates islands operation  In Crete, the largest Greek island, RES annual energy penetration reaches 20%, hourly penetration might exceed 50%.  For secure and economical operation with increased RES penetration advanced EMS are required  MORE CARE provides advanced forecasting, scheduling and security warning functionalities.

38. Thank you!