Power Electronics in Hybrid Energy Networks

1. Power Electronics in Hybrid Energy Networks Johan Enslin David Elizondo Johan.Enslin@kema.com Delizondo@kema.us KEMA Inc. T&D Consulting Raleigh, NC USA

2. Outline • The Future of Energy • Hydrogen Economy • Hybrid Hydrogen Economy • Energy Web Concept and Distributed Power • Power Electronics’ role in the Future of Energy • Interconnection of Large-scale PV • Interconnection of Wind Energy • Energy Storage’s and FACTS role in the Future of Energy

3. Hydrogen Hope and Gamble

4. Grid-less Hydrogen Society?

5. Hybrid AC/DC Networks Peak Shaving Fuel Cell O2 Gas H2 Gas Hydrogen Storage • Electrolyzer • Water purification • Regulators • - Gas dryer • Integrated Heating • CHP + Power Electronics - Grid Interconnection - STATCOM / APF - Max Power Tracker - Electricity Storage - Transfer Switch Local H2 Use Control, Protection Comms V - H2 Trucking H2 Pipeline Water Supply Electrical Interconnection Transport DP - Network - Hydrogen Hybrid System Concept

6. Market Energy Web Concept Factory CHP Central Generation Microturbine Substation Wind Commercial CHP Decentralized DER Dispatch Data Centers Storage Pumped Storage Fuel Cell Flow Batteries Flywheel Residence Fuel Cell Car Gas Turbines Photovoltaic Power & Communications Links

7. Energy Web Concepts • Characteristics of Energy Supply in 2010 • Nuclear Generation: Upgrade and Replace Centralized Nuclear Generation and Small Scale Pebble Bed Modular Nuclear Reactors • Gas & Electrical Networks merge – Move to Hydrogen • Renewable Energy Generation: Targets 10 - 20% (Environmental) • High premium on Network Reliability and Security • Shift from power supply to service orientated culture

8. Energy Web Concepts--Cont • Technology • Higher Efficiency for Distributed Generation • Flexible and lower cost power electronic interfaces • Less NOx and CO2 generation • Low-cost, flexible energy storage • Interconnections and Regulations • Standardization of Power and Communication Interfaces • Simplified regulations for small DP • Safety considerations in island operation • Formation of self-sustained islanding mini grids

9. Energy Web Concepts--Cont • Distributed Power has to Offer: • “Plug & Play” Functionality with enforced standards • Intelligent Communicating Components – Extra services • Network Reliability, Quality, Stability and Security built-in Power Electronics • Multi-fuel driven micro-turbine technologies • High efficiency technologies with CHP functionality • Interface Between Hybrid AC / DC / Gas / Hydrogen Networks

10. Distributed and Renewable Power • Dutch Government and Utilities promote use of renewables with subsidies and customer programs. • Dutch generation • > 35% distributed CHP • Wind (10%) • Some whole suburbs are installed with roof-mounted PV arrays • Nieuwland • 500 homes in total 12 000 m² PV. • 1 GWh Renewable Energy • 6 GW off-shore wind power is currently planned for 2020. Amersfoortse suburb Nieuwland

11. Distributed Power Trends 2010

12. Interconnection Issues with DP • Power Quality considerations on system level • Background system distortion; All indices; Network Resonances • Require integrated mitigation solutions • Protective Relaying Considerations • Feedback Power • Islanding • Voltage and Angular Stability • Distribution Networks behave like Transmission Networks • Require innovative solutions – FACTS; Storage; Hybrid Networks • Interconnection Standards and Guidelines • Crucial to do updates: • IEEE 1547 , IEC 61400-21 , EN 50160

13. Case A: Interconnection of Large-scale PV

14. Interconnection Issues with DP inverters • 200-500 Homes with PV panels • 1-3 kW PV inverters, connected at 220 Volts feeder • 1GWh is generated annually • By Measurements at the site… • Voltage regulation and Flicker: • Exceeding voltage limits and inverters trip • Voltage fluctuations due to power fluctuations • Harmonics: • Inverters individually satisfy IEC 61000-3-2 specification • EN 50160 can temporarily be exceeded. • Inverters trip unexpectedly 14

15. Interconnection Issues with DP inverters • Attention Points on Standards • Effect of background supply distortion • Increased distortion due to a resonance phenomenon • Islanding may be a good alternative

16. Case B: Interconnection of Wind Energy

17. Network Interconnection of 6 GW Wind • Feasibility of 6 GW Wind Power in 2020 • Total cost 10.000 M€ • Stability Issues and Reactive Power Compensation • Required 350 M€ - 650 M€ network upgrades • Conventional solution requires 100 M€ expenditure

18. Energy Storage for 6 GW Wind Farm • Possible savings of 250 M€ - 550 M€ network upgrades if storage is included • Requires 2,5 GW and 62 GWh storage for 6 GW wind farm

19. Storage Options for 6 GW Wind Farm VSC Interface • Based on Flow-battery technology • 6,000 M€, 30 years NPV, 1x1 km size • Not feasible by factor 10 as a single solution

20. Integrated Storage Approach • Primary Application: • Wind Power Stabilization. • Secondary Applications: • Interface of Constant Speed Offshore Wind Turbines • Power Balance and Reserve Power Management • Power Quality and Reactive Power management • Spinning Reserve Management • Black-start Availability • Stop-start Reduction of generating units • Network security - UPS operation

21. Conclusions • Hydrogen economy • Will be gradual process with DP playing a key role • An excellent opportunity for power electronics – Mobile & Stationary applications • Distributed Power • Preferred option to integrate renewables at high network reliability, stability and security levels • Power electronics are key for better DP interconnections

22. Conclusions--Cont • Interconnection Issues • Large-scale wind energy interface provide major network interconnection challenges – Hydrogen hybrids • Design and control of DP converters for system integration needs attention • Futuristic View… • Cost effective H2 and electricity storage together with Power Electronics.

23. Hybrid Wind Network Options

24. Distributed Power: Mobile NECAR HYPERCAR

25. CHP Energy Storage for Renewable and Distributed Power