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EFFICIENT & SAFE ELECTRICAL ENERGY STORAGE CAPABILITIES WITHIN SOUTH AFRICA

Andries J. van der WaltB-Engineering (Electrical & Electronic) – UJ

Study Supervisors: Prof JHC Pretorius and Dr. J.H. Enslin

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Overview Background Problem Statement Proposed Research Topic Existing Technologies Renewable Energy Growth Ancillary Services of SA Future Research Plans Q&R

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Background B-Engineering (Electrical and Electronic) @ UJ Eskom:

Engineering System Processes – 3 months Smart Plant Electrical – 3 months Electrical Departmental Rotation – 6 months Medupi Power Station – 12 months

System Engineer – Turbine Plant Generator and supporting auxiliaries LV Switchgear and Control Gear Export System – ECS, Gen Protection, GCB ACC Cooling System

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Problem Statement

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Proposed Research Topic Directly storing Electrical Energy Safely

and Efficiently from the point of harvesting it to a point of were it is needed.

Storing the electrical energy in larger quantities than currently possible – UPS System for the National GRID?

Alternatively, UPS backup for a town or city’s electrical requirements for at least 24 hours.

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Existing Technologies

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Existing Technologies

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Renewable Energy Growth

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Ancillary Services of SA1. Grid Support in terms of Reactive

Power Supply and Voltage Control2. Electrical Energy Reserves3. Constrained Power Generation4. Black Start-up Capability 5. Islanding Capability

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Grid Support in terms of Reactive Power Supply and Voltage Control

SAGC Requirement for the existing Eskom Conventional Plants.

SAGC requirement for renewables including IPP's.

Voltage Control requirement. SCO requirement.

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Electrical Energy Reserves Instantaneous Reserve Regulating Reserve 10-Minute Reserve Supplemental Reserve Emergency Reserve

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Constrained Power Generation Cape constraint - Koeberg is restricted to refuel

outside of winter from 01 May to 31 August. Arnot Power Station is constrained during the

loss of the 800MVA 400/275KV coupling transformer.

Arnot 400/275kV transformer overload constraint.The requirement is:

○ Peak: 2 x 275kV units online.○ Off-Peak: 1 x 275kV unit online.

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Black Start-up Capability General Requirements. Technical Requirements for Black Start

Facilities. Additional Requirements For Pump Storage

or Hydro Black Start Facility. Required Black Start Diesel Generator Tests

per Year. The Black start Capabilities of Renewable

Energy Sources

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Islanding Capability Grid Code Requirements. Prototype and Routine Tests.

Remain in an islanded state for a minimum of two hours at full load.

Routine tests on units shall be performed after each general overhaul or six years.

Planned Unit Islanding Tests and Expected Incidents.

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Future Research Plans Grid Infrastructure Support Energy Security of South Africa Peak Shaving Energy Access Storage Possibilities

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Q&R Questions?

Recommendations?