System Services by Wind Power Plants The industrial point of view Eckard Quitmann Head of Sales - Grid Integration Dena Symposium, November 8th 2018

Transcription

1 System Services by Wind Power Plants The industrial point of view Head of Sales - Grid Integration Dena Symposium, November 8 th 2018

2 Agenda 1. System needs 2. Practical experiences 3. New features to achieve 100% RES penetration 4. Conclusion 2

3 System Needs The relevant horizon: The Synchronous Zone Sync. zone = AC-interconnected system Instantaneous penetration energy penetration Each country has its own concept of Minimum, mandatory requirements Ancillary Services Ongoing discussion about RfG implementations, future system needs and additional technical features Aim: A power system to run stable with 100% instantaneous penetration of decentral, inverter-based, volatile generation (RES-based) 3

4 System Needs Traditional 4 Ancillary Services (AS) AS evolved historically AS assume the permanent dominance of synchronous generators Products tailored to the capabilities of synchronous generators Are not enough for a 100% inverterbased future! Source: dena Ancillary Services Study

5 Practical experiences Ancillary Service: Voltage Control by a Wind Farm U-control Technically proven WF contributes to local U-control Reactive power capability causes CAPEX Reactive power provision causes OPEX Remuneration internationally very diverse, usually for RES: none 5

6 Practical experiences FFR POR Ancillary Service: Frequency Response (FFR & POR Requirements) Increase MW output within 2s of start of an event Sustain increase for at least 8s Extra energy gain from 2 to 10s must be greater than energy lost from 10 to 20s Magnitude of MW response adjustable between 0%-10% of rated power Increase MW output within 5s of start of an event Sustain increase for at least 10s Additional MW output at frequency nadir or minimum during the 5 to 15 seconds Source: EirGrid 6

7 MW Practical experiences Inertia Emulation response, for FFR and POR <0.5s rise time: higher payment (>2x) Recovery energy: meets FFR & POR requirement 51,00 50,80 50, , second duration meets FFR and POR requirements 50,20 f (Hz) 50,00 49, ,60 49, t (s) MW Output Frequency (Hz) 49,20 7

8 Practical experiences Market for Ancillary Service: Frequency Control ( Balancing ) Frequency reserves Technically possible with WF Capability causes low CAPEX Provision causes OPEX Products, remuneration and obligations internationally very diverse For RES unusual to participate Shape of market products is key: Short products length Short lead time Unsymmetrical products Source: Dr. Sigrid Bolik, SENVION, based on input from ERCOT; AEMC; Hydro-Québec TransÉnergie, TenneT TSO 8

9 Practical experiences Market development for Ancillary Service Frequency Control ( Balancing ) Frequency reserves Shape of market products is key: Short products length Short lead time Unsymmetrical products More volatile RES doesn t mean automatically more Balancing needed! Source: ELIA grid Int. German Paradox Demystified: Why is Need for Balancing Reserves reducing despite increasing VRE Penetration? 16 th int l Wind Integration Workshop, Berlin, Germany, Oct

10 System Needs What might be system needs in future? When, where, to what extent will which subject Inertia and/or fast primary response? Mitigation of volatility and dp/dt? Mitigation of negative sequence voltages? Damping of low-order harmonics? Damping of power system oscillations? Protections & short-circuit currents? Static and transient stability limits? Resynchronization and black start? Models for all phenomena? become critical for the system? Preliminary result for central European synchronous zone: Not critical Not critical 10

11 Practical experiences Records of instantaneous penetration Example1: Germany 66 % Source: Strommarktdaten ca. 100% BUT: Germany located in the middle of huge synchronous zone Neighbors with very low instantaneous penetration 11

12 Practical experiences Records of instantaneous penetration Example 2: Ireland Isolated Synchronous Zone Up to 81,5% instantaneous SNSP (System Non-Synchronous Penetration) Wind farms curtailed to 72% (wind generation MW / forecast) 65% SNSP is tested and approved (not requiring any emergency action) Advanced scheme for ancillary services Traditional inverter technology in WECs Source: EIRGRID smartgriddashboard.eirgrid.com 12

13 Practical experiences Records of instantaneous penetration Example 3: Faroe Islands Isolated Synchronous Zone Political aim: 100% RES in 2030 Electrical load MW 2 Wind farms, in total 18 MW 1 Battery storage 2,3 MW / 0,7MWh Function: Ramp-Rate control Traditional inverter technology in WECs and Battery inverter All owned and operated by SEV, no commercial AS scheme Source: SEV, local power system operator 13

14 Practical experiences Lessons learned I 60% 80% instantaneous penetration of wind+pv is technically possible with todays inverter technology RES can technically contribute to some ancillary services Typically for RES not profitable to contribute to traditional AS AS product- and market-design is key 81% inst. SNSP 14

15 Practical experiences Lessons learned II System Needs depend on physics of the power system (size, interconnectors, meshing ) What is the dimensioning contingency case that the power system shall survive without blackout? Remaining synchronous generator technology (run-river hydro plants, gas turbines ) Capabilities of already built inverter-based generation Scheme of ancillary services Lots of questions open Technical Organizational Commercial Source: UCTE Final Report System Disturbance on

16 New features to achieve 100% RES penetration Aim: Keep prices for end consumer down! Determine the system needs Describe the needed performance technology agnostic Differentiate corresponding features Keep in mind: All such features have CAPEX and/or OPEX. Industry only develops what customers buy! Decide smartest way to ensure needed AS provision 24/7 17

17 New features to achieve 100% RES penetration Aim: Keep prices for end consumer down! Decide smartest way to ensure AS provision 24/7 System compatible = minimum requirement to connect, no System serving = providing a service to the system,!? 18

18 New features to achieve 100% RES penetration Who to decide what is what? Commercially highly relevant (CAPEX & OPEX) Energy industry to make proposals Politics + Regulator to decide System compatible = minimum requirement to connect, no 50.x Hz FRT FFCI minimum Online com. Low I harmonic Politics & Regulator! FCR, FRR Q/U-control Black start Inertia Active Damping System serving = providing a service to the system,! 19

19 Conclusion Wind&PV can technically offer some AS Future of Ancillary Services is becoming more complex Political decision to distinguish System compatible System serving No technical reason not to reach 100% RES (or very close) Precondition: System Need identification Industry is interested to keep markets for WECs, but no altruistic players available 20

20 Conclusions Thank you 21