Dr.-Ing. Ervin Spahi, Wadden Sea Forum, Bremerhaven Electric grid on and off-shore: current status, obstacles and new developments

Transcription

1 Dr.-Ing. Ervin Spahi, Wadden Sea Forum, Bremerhaven Electric grid on and off-shore: current status, obstacles and new developments November 26, 2009 Slide 1

2 Transmission grid The challenges Optimal utilization of regional advantages Growth of interconnected systems Renewable energy integration Short-term changes in load flow Restricted access to information for system operators The grids must become more flexible from structural as well as from operational point of view! November 26, 2009 Slide 2

3 Critical issues Regulatory / Financial Rules for investment Environment Public opinion Overhead line vs. cable Technical Voltage Compatibility November 26, 2009 Slide 3

4 Transmission technologies November 26, 2009 Slide 4

5 AC (Alternate Current) Transmission Overhead lines Standard technique for the transmission of electrical energy in Germany and Europe (220 and 380 kv) Voltage levels up to 765 kv in Russia, USA and Canada in operation kv planed in China and Japan Advantages: Simple and fast construction Proven and low-cost technology Easy to integrate in existing systems Disadvantages: Optical impact, wide corridors Relatively high power losses November 26, 2009 Slide 5

6 AC (Alternate Current) Transmission Overhead lines - developments Using of FACTS (Flexible AC Transmission Systems) Partial control of the voltage and load flows Temperature Monitoring Using of actual weather conditions (wind, sun, ice ) High temperature conductors Operating temperatures more than 200 o C Wide Area Monitoring (WAM) Optimized use of existing transmission lines November 26, 2009 Slide 6

7 AC (Alternate Current) Transmission Cables Oil/mass impregnated cables (since beginning of 20 th century) Voltage level up to 420 kv Conductor cross section up to 2000 mm 2 XLPE cable (since 1971) Up to 500 kv Conductor cross section up to 2500 mm 2 Power up to app MW per system Both as sea cable (max. power up to app. 350 MW, 245 kv) Advantages: Proven technology in medium voltage level (up to 110 kv) Low optic impact Disadvantages High investment costs Reactive power compensation for longer distances Lack of experience November 26, 2009 Slide 7

8 AC (Alternate Current) Transmission Cables - developments Online temperature monitoring Isolation new techniques Increase of voltage levels and currents Super conducting cables Ongoing development Uncertain application in the near future November 26, 2009 Slide 8

9 HVDC (High Voltage Direct Current) Transmission Classical technology Transmission voltage up to +/- 800 kv OHL and +/-500 kv cables (oil cables) Classical technology with over 50 years of experience Developed for the application for long distances (OHL), sea connections and connection of two non-synchronous systems Transmission power MW Advantages: Lower losses No distance limitations Control possibilities Disadvantages: Point-to-point connection (multiterminal possible but complicated) Additional costs and losses of converter stations November 26, 2009 Slide 9

10 HVDC (High Voltage Direct Current) Transmission New technology HVDC Light VSC Voltage Source Converter HVDC technology Using IGBT (insulated gate bipolar transistors) Possible application of XLPE cables up to +/-320kV Transmission power: MW Independent from the system (self control) Active and reactive power control Multiterminal application grid possibility November 26, 2009 Slide 10

11 Development of HVDC transmission technology Power/pole Classic MW Light MW Classic kv Light kv Commissioning year Inbetriebnahmejahr November 26, 2009 Slide 11

12 Development HVDC Light land cables Capacity rise 400 times in 10 years 1997 Hellsjön ± 10 kv 3 MW 2000 Directlink, 354 km ± 80 kv, 60 MW 2001 Murraylink, 360 km ± 150 kv, 220 MW 2004 Estlink, 210 km ± 150 kv, 350 MW 2008 ± 320 kv, 1,100 MW November 26, 2009 Slide 12

13 Transmission grids - visions November 26, 2009 Slide 13

14 Off Shore Super grid concept Combine: Connection of off shore wind Interconnections for trading Sharing of back-up power Benefits Reduced investment Increased reliability Source: Airtricity November 26, 2009 Slide 14

15 Building a European Smart Super grid 1. Introduce HVDC Light 2. Use EU stimulation package to expand 3. Start connecting individual projects November 26, 2009 Slide 15

16 Building a European Smart Super grid 1. Introduce HVDC Light 2. Use EU stimulation package to expand 3. Start connecting individual projects 4. Build the grid Opportunity for Europe to maintain the lead in renewable energy and transmission technology November 26, 2009 Slide 16

17 Offshore November 26, 2009 Slide 17

18 HVAC vs. HVDC cable 1500 Power [MW] Distance [km] 245 kv ac cable 320 kv dc cable. November 26, 2009 Slide 18

19 2000 MW 10 x 200 MW AC grid connection Platform AC Cable November 26, 2009 Slide 19

20 2000 MW 2 x 1000 MW HVDC Light cable Platform DC Cable AC Cable November 26, 2009 Slide 20

21 2000 MW - future 1 x 2000 MW HVDC Light cable + Multiterminal Platform DC Cable November 26, 2009 Slide 21

22 Onshore November 26, 2009 Slide 22

23 Offshore wind integration in Germany High wind High load scenario Power (MW) Benchmark case Offshore Line corridor November 26, 2009 Slide 23

24 Transmission corridors AC transmission line require large corridors November 26, 2009 Slide 25

25 Transmission corridors AC DC transmission line transmitting line require as much large power corridors requires fewer towers November 26, 2009 Slide 26

26 Transmission corridors AC HVDC transmission line conserves transmitting line forests require as and much large saves power corridors land requires fewer towers November 26, 2009 Slide 27

27 Transmission corridors AC HVDC transmission line conserves transmitting HVDC line forests require cables as and much large saves power corridors land requires fewer towers November 26, 2009 Slide 28

28 Transmission corridors November 26, 2009 Slide 29

29 Solutions November 26, 2009 Slide 30

30 HVDC Light Projects 9 projects in operation 4 under construction Tjäreborg 2000,7 MW Valhall 2010, 78 MW Troll 2004, 80 MW Estlink 2006, 350 MW Cross Sound 2002, 330 MW Gotland 1999, 50 MW Eagle Pass 2000, 36 MW EWIP 2012, 500 MW BorWin , 400 MW Hällsjön 1997, 3 MW Directlink 2000, 180 MW Caprivi Link 2010, 300 MW Murraylink 2002, 220 MW November 26, 2009 Slide 31

31 HVDC Light in Europe Examples Nord E.ON MW / 150 kv 128 km sea cable 75 km land cable Eirgrid 500 MW / 200 kv 186 km sea cable 70 km land cable November 26, 2009 Slide 32

32 Nord E.ON 1 BorWin 1 Land and sea cable burial November 26, 2009 Slide 33

33 BorWin1 The last steps until completion of the installation November 26, 2009 Slide 34

34 Future November 26, 2009 Slide 35

35 Next development steps HVDC Classic and HVDC Light Higher reliability Lower footprint Environmentally adapted HVDC Classic 1000 kv..maybe HVDC Light Higher ratings Lower losses More compact, particularly offshore Multiterminal Control features DC Grids November 26, 2009 Slide 36

36 Conclusion Integration of renewable energy, dislocation of conventional power plants, increased transit of power inside the Europe set new challenges to the transmission grids The reinforcement of existing and built of new transmission lines will have to be done Modern HVDC technology can make a significant contribution, especially for offshore grids Technical possibilities have to be considered for each project November 26, 2009 Slide 37

37 November 26, 2009 Slide 38