Wave Powerfor the

Western Cape

Kenneth Pedersen

PRESTEDGE RETIEF DRESNER WIJNBERG (PTY) LTD

Presentation Outline

• Introduction

• SWEC– Original Development– Viability for Western Cape– Future Development

Introduction

Granger Bay

Lamberts Bay

SA Ocean Energy Research

• Creation of Ocean Energy Research Group

• Assessment of Wave Power Resource - 1978

• Initiation of Stellenbosch Wave Energy Converter (SWEC) Project - 1979

• SWEC Development and Evaluation – 8 yrs

• SWEC Project shelved – late 1980’s

Wave Power Levels – SA

20

30

45 13

12

Units: kW/m crest lengthPredominant Wave Direction

25

SWEC – Design Philosophy

• Must generate electricity at competitive cost

• Must avoid the need for costly over-design (extreme storm conditions)

• Must preferably utilise high in-shore energy levels

SWEC – Design Philosophy

• Must not interfere with shipping routes and fishing industry

• Must be within local technological capability

• Must have minimum visual and environmental impact

SWEC -One “V”

Air Ducts

Chambers

Submerged CollectorArms - “V”

WaveDirection

Mounted on Seabed

Water Depth: 15m – 20m

1.5 km from shore

Water LevelOscillates

High P

Low P

AC Electric Generator

Seabed CableAir Turbine in

Generator Tower

Wave Crest

High Pressure Phase

TrappedAir Pocket

High PressureAir Duct

SWEC - Concept

Wave Trough

Low Pressure Phase

TrappedAir Pocket

Low PressureAir Duct

SWEC - Concept

-

Model Studies – 2D

-

Model Studies – 2D

-

Model Studies – 3D

Proposed Site

National Grid

Power Stations

Wave Powerfor the

Western Cape

SWEC -Array Collector

Substation

Sea

bed

Cab

le

Shore Line

National Grid15

00m

Wave Direction

SWEC “V” Units

Constructionand Installation

1. Pre-cast units to be constructed in a casting harbour in Saldanha Bay.

2. Towed to site suspended from a placement barge.

3. Lowered onto prepared bed.

4. Connected to adjacent unit and secured (ballast rubble or piling).

Placement Barge

Example of SubmersedTunnel Construction

Installed Unit

Unit suspendedfrom Barge

SWEC – Power Generation

One “V”Total

(40 km)

Rated (Design) Capacity

5 MW 770 MW

Annual Average

2 MW 308 MW

Winter Average

2.9 MW 450 MW

Generating Costs

• Wind PowerActual (2006): 50–60 cents / kWh

• Wave Power (SWEC)Pre-feasibility (2006): 60–75 cents / kWhFeasibility : To be determined

SWEC – Future Development• Phase 1: Feasibility Study

• Phase 2: Detail Design (5 MW Demo Unit)

• Phase 3: Implementation (5 MW Demo Unit)

• Phase 4: Testing (5 MW Demo Unit)

• Phase 5: Implementation (770 MW)

SWEC - ProgrammeYear 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Year 8 Yea r 9 Year 10 Year 11

SWEC Phase 1

Development Phase 2

Phases Phase 3

Phase 4

770650

520390

260

Rated Output (MW) 1305

Phase 5

Wave Energy for the Western Cape

Discussion

PRESTEDGE RETIEF DRESNER WIJNBERG (PTY) LTD