Wind Energy Grid Integration

1
Wind Energy Grid Integration

• Compiled and presented by
• Riaan Smit
• Chief Engineer Network Planning
• 2009-03-19

2
Content

• Scope
• Best Practices for Wind Energy
• Regional Requirements
• South African Grid Codes
• International Grid Codes
• Embedded Generation
• Safety standards
• International Research Norms
• Where is this so called Grid?
• Cost of Grid Integration
• Recommendations Conclusions

3
Scope

• The role and impacts of norms, standards and
  codes of good practice in promoting renewable
  energy in South Africa.
• Focus on Wind Energy Facilities
• And electrical grid infrastructure integration

4
Best Practices for Wind Energy

• Best practices not available in South Africa, as
  yet
• Best Practices Guidelines for Wind Energy
  Development
• By British Wind Energy Association - Nov 1994
• Later adopted by European Wind Energy Association
• Also adopted and enhanced by Australian Wind
  Energy Association March 2002
• Best Practices Guidelines for Implementation of
  Wind Energy Projects in Australia
• Recommendation
• SAWEA to cooperate with BWEA, EWEA and AusWEA
• in adopting similar guideline
• enhance for South African conditions and legal
  requirements

5
Technical Commercial considerations Environment
al Considerations Dialogue / Consultation And
YES It is happening w.r.t. electrical
infrastructure already in South Africa
European Best Practice Guidelines for Wind
Energy Development
by European Wind Energy Association
6
Regional requirements

• Environmental Considerations covered by
• Strategic Initiative to Introduce Commercial Land
  Based Wind Energy Development to the Western Cape
• Towards a Regional Methodology for Wind Energy
  Site Selection
• Report 5 Proposed Regional Methodology
• Excellent detailed Methodology
• 7.2.2 The issue of cumulative impact is
  imperative to address and forms an important part
  of the proposed regional method. Minimum
  distances between large windfarms are recommended
  at 30km, with preference being greater than 50km
• Minimising cost, sharing optimisation of grid
  infrastructure may require negotiations.

7
South African Grid Codes

• The South African Grid Code The Network Code
• Focused on large scale generation
• No specific conditions for renewable energy
• Distribution Network Code, September 2007
• 8.1 Responsibilities of Embedded Generators to
  Distributors
• 8.2 Responsibilities of Distributors to the
  Embedded Generators
• Also to be used by Renewable Energy Facilities
• Specify operating requirements
• Voltage, frequency, protection, earthing,
• Low Voltage Ride Through (LVRT) capability
• To be considered for larger Wind Energy
  Facilities
• Unlikely for units connected to Medium Voltage
  networks alone

8
International Grid Codes

• Ireland
• Island network size of Eskom Western Region
• Distribution Code by ESB Networks, CER approved.
  October 2007
• A1. Generating Plant gt10MW and subject to central
  dispatch.
• A2. Generating Plant gt2MW and not subject to
  central dispatch.
• A3. Generators lt2MW.
• A4. Customers with CHP or Customers with
  Auto-production.
• A5. Customers with stand-by generators.
• Caters for various types and classes of
  generators
• Germany
• Grid Code High and Extra High Voltage. E.ON Netz
  GmbH, Germany. April 2006
• Well referenced Grid Code by various countries
• Set good examples for voltage and frequency
  criteria

9
Embedded Generation

• To fulfil Eskom Distributions obligation under
  Section 8.2 (4) of the South African Distribution
  Code Network Code
• The Distributor shall develop the protection
  requirement guide for connecting Embedded
  Generators to the Distribution System to ensure
  safe and reliable operation of the Distribution
  System.
• DST 34-1765 Distribution Standard for the
  interconnection of Embedded Generation
• Applicable to renewable energy facilities
• Acknowledge further development of standard to
  cater for
• e.g. Wind Energy Facilities
• Low voltage ride through capability
• Frequency operating range

10
Safety Standards

• OHSAct - various safety requirements
• Already covers electrical infrastructure
• International standard IEC 61400 series for Wind
  Turbines, e.g.
• IEC 61400-1 Design requirements
• IEC 61400-2 Design requirements for small wind
  turbines
• IEC 61400-12-1 Power performance measurements
• IEC 61400-21 Measurement and assessment of power
  quality
• IEC 61400-24 Lightning protection
• Eskom standards for Transmission Distribution
  systems
• Various NRS standards, e.g.
• NRS048 for Quality of Supply of electrical
  supplies
• NRS076 for earthing requirements

11
International Research Norms

• A vast amount of info on internet
• Consider up to date Magazines, e.g.
• Renewable Energy World,
• Wind Directions from EWEA, etc.
• Natural Resources Canada www.retscreen.net
• for various renewable energy software
• training material
• case studies
• EWEA AWEA websites Conferences
• CIGRE Renewable Energy WG
• South African case studies to be developed and
  published increase participation
• Develop SA requirements for e.g. much warmer
  climate

12
Where is this so called Grid?

• Assumptions
• Main substation grid areas
• Develop closer to main lines?
• 66kV 132kV
• Weaker inland networks
• Coastal winds?
• Less wind resource inland?
• How much?

13
Cost of Grid Integration

• The Cost of Transmission for Wind Energy A
  Review of Transmission Planning Studies (February
  2009)
• USA review of a sample of 40 detailed
  transmission studies that have included wind
  power 2001 2008
• total transmission cost / total amount of
  incremental generation capacity (wind and
  non-wind)
• Majority of studies unit cost of transmission
  lt500/kW
• or roughly 25 of the current 2,000/kW cost of
  building a wind project
• The median cost of transmission from all
  scenarios in sample is 300/kW, roughly 15 of
  wind project cost
• Aggregate range of transmission costs is from
  0-79/MWh with a median of 15/MWh and most
  studies falling below 25/MWh.
• WTG ave roughly R20 mill/MW Grid ave R3-5
  mill/MW

14
Any actions?

• While awaiting REFIT (thanks for breather space)
• Discussions with various developers
• Eskom MTPPP request for generation
• DME initiative for Renewable Energy
• Germany GTZ agreement with Western Cape Province
  DEADP
• Eskom participant in agreement
• Grid Integration of Wind Energy seminar 24-25
  March 2009, sponsored by GTZ Western Cape
  Province DEADP
• Invite to Developers, consultants,
  Research/Academics, City of Cape Town, Eskom and
  other role players, e.g. DME NERSA
• Eskom workshop to create wind energy scenarios
  from 50 500 5000 MW, also invited researchers
  and consultant.
• Public participation session May 2009
• Complete grid scenarios and various technical
  studies July 2009, in cooperation with DigSilent
  (sponsored by GTZ)

15
Recommendations

• Expect major role from SAWEA for guidelines and
  influence
• Developers
• Consultants
• Industry (OEM Manufacturers, suppliers, etc.)
• Environmental
• Utilities (Eskom, Municipalities)
• Grid Integration studies to be completed
• Cooperation between developers to minimise grid
  infrastructure
• e.g. Share EIA and cost for line routes
• SA Grid codes to be revised to accommodate wind
  turbine technologies
• Focus on knowledge and skills transfer Human
  Capacity

16
Conclusion

• There are certainly best practices, various
  guidelines, standards and international
  cooperation
• Ready to support renewable energy
• The sun sets in the west,
• but wind energy dawns in Western Cape

17
References

• Renewable Energy Policy of South Africa.
  2004-09-06. http//www.info.gov.za/whitepaper/.
• Best Practices Guidelines for Wind Energy
  Development. British Wind Energy Association. Nov
  1994. www.bwea.com
• Best Practices Guidelines for Wind Energy
  Development. European Wind Energy Association
• Best Practices Guidelines for Implementation of
  Wind Energy Projects in Australia. Australian
  Wind Energy Association. March 2002.
  www.auswea.com.au
• Strategic Initiative to Introduce Commercial Land
  Based Wind Energy Development to the Western
  Cape. Report 5 Proposed Regional Methodology
  Towards a Regional Methodology for Wind Energy
  Site Selection. Provincial Government of the
  Western Cape. May 2006
• The Cost of Transmission for Wind Energy A
  Review of Transmission Planning Studies. Andrew
  Mills, Ryan Wiser, and Kevin Porter. Ernest
  Orlando Lawrence Berkeley National Laboratory.
  February 2009. Download from http//eetd.lbl.gov/E
  A/EMP
• Call for an expression of interest from entities
  willing to generate electricity from renewable
  energy sources. DME. 2008
• South African Grid Code (all parts). NERSA.
  August 2005.
• South African Distribution Code (all parts).
  NERSA. October 2007.
• Grid Code High and Extra High Voltage. E.ON Netz
  GmbH, Germany. April 2006
• Distribution Code by ESB Networks, CER approved.
  October 2007
• NRS 048 Electricity Supply Quality of Supply
• IEC 61400 series standards for wind turbine
  systems