Coega CCGT Power Plant Project

By: Black & Veatch / Eskom

25 July 2006

Table of ContentsA. Introduction

1. Need

2. Project background

B. Power plant

1. Gas Turbine Technology

2. Cycle Configuration

3. Equipment, systems & facilities

4. Site buildings

5. Emissions

6. Noise levels

7. Cooling System

8. Water Supply

9. Wastewater & Sewage Treatment Systems

10. Fire Protection

C. Site Layout & LNG Integration

D. Project Milestones

A. Introduction

1. Need

• In March 2006, Eskom Board supported the Combined Cycle Gas Turbine (CCGT) project strategy to have the first 800MW available in the first quarter of 2009.

• Project seen as a potential option to:– Help resolve the Cape problems– Strengthen regional supply– Stabilise the grid– Anchor project for IDZ

2. Project Background

• Coega CCGT Project under evaluation since 2004.

• Project being developed jointly with iGas (a subsidiary of CEF, also a state owned entity):– iGas developing the LNG import and regasification terminal– Eskom developing the power station

• Provision for a maximum of 3200MW has been made at the current site.

• First 800MW to be commissioned prior to the LNG regasification terminal being commissioned; therefore liquid fuel firing would be used in the first 12 to 18 months until the terminal is ready to supply natural gas.

B. Power Plant

1. Gas Turbine Technology

• Project Requirements:800 MW by March 2009.

Eventual 2400 MW Combined Cycle & 800MW open cycle. Total will be 3200MW.

Initial operation on distillate fuels until LNG available in 2011.

First 800 MW will be Open Cycle to accommodate schedule.

1. Gas Turbine Technology (continued)

• Turbine TechnologiesF-Class: Best fit for combined cycle (CC); higher

efficiency and proven reliability in CC operation with natural gas. Also good match of MW output to project.

E-Class: Good when burning primarily liquid fuels.

1. Gas Turbine Technology (continued)

• Gas Turbine Suppliers:

General Electric (GE), Mitsubishi Heavy Industries (MHI) and Siemens are all viable options.

Alstom has expressed concerns over long term operation on distillate fuels. Difficult to operate GT in Open Cycle.

All four vendors are able to execute project as an equipment only supplier (complete Power Island) or EPC Turnkey.

2. Cycle Configuration

• Recommended Coega Cycle Configuration Two blocks of 3x1 configuration using F-Class CTs.

First block will be initially in Open Cycle mode to meet goal of 800 MW by March 2009. It will produce 1200MW by the end of 2009 in combined cycle mode.

First block will be operated on liquid fuel until LNG available.

Second 3x1 block will be completed in time for 2011 operation on LNG.

3. Equipment, systems & facilities

The following is a list of major equipment, systems and facilities:

2 blocks of 3 x 1 Combined Cycle units, Combustion Turbines with HRSGs

Each block – 400 MW steam Turbine

Once through sea water cooling – Surface condenser with Titanium tubes.

Desalination System.

Air Compressors and dryers

Fuel Oil Storage tanks and unloading facility

Demin Water Tank

Firewater/Service water Tank

Condensate Storage tank

Intake cooling water structure with Pumps, screens

3. Equipment, Systems & Facilities (continued)

• The following is a list of major equipment, systems and facilities (continued):

Intake cooling water pipe and discharge canal

Auxiliary Boiler.

Wastewater Treatment System

Emergency Diesel Generators

8 MW Black start Diesel Generator

2 – 100 Ton Bridge Cranes with aux Hoists.

Hydrogen Generation system

Hypochlorite Generation System

Demin water system.

Condenser Tube Cleaning System.

CEMS

3. Equipment, Systems & Facilities (continued)

• Heavy haul:– Steam turbine generator stator: LxWxH = 12m x 5.5m x 4.85m,

shipping weight = 314,000 kg

– Steam turbine step-up transformer: LxWxH = 8m x 4.2m x 5m, shipping weight = 270,000 kg

– HRSG HP drum: LxDia = 13m x 3.1m (including shell projections), shipping weight = 143,000 kg

– Largest HRSG tube bundle section (probably the HP economizer or evaporator section): LxWxH = 25m x 4.3m x 3.4m, shipping weight = 218,500 kgs

• Note: Transportation of equipment may be an issue.

4. Site buildings

The HRSG does not include duct firing.

Pilings are assumed for all major foundations, and spread footers of other foundations. Further stabilization of the existing subgrade is also not included.

The following Site Constructed buildings are included:

ST Generation and CT Buildings

Three story Admin/Maint/warehouse building

Demin Water Treatment Building

Desalination Building

Water Treatment Building

5. Emissions

• Air emission sources will be the combustion turbines (6), emergency diesel generator (1), and auxiliary boiler (1).

• The World Bank NOx emission limit for combustion turbines burning diesel is 165 mg/Nm3 with a provision for increase to 400 mg/Nm3 if there are technical difficulties, such as scarcity of water for injection.

• World Bank standards will be met when burning diesel or natural gas.

• SO2 emissions are dependent on fuel sulfur content.

• Water injection may be required to meet combustion turbine NOx emission requirements when burning diesel.

6. Noise levels

• Imposing requirement of 85 dBA at 3 feet from individual equipment.

• Can impose site boundary limitations if necessary to meet NPA, CDC, or national standards.

• Installing silencers on steam relief valves and startup vents to minimize noise during startup and upset conditions.

7. Cooling system

• Once through cooling using seawater with a maximum 7oC temperature rise.

• Performing a heat rejection comparison between once through cooling and cooling tower to confirm once through cooling is the most economical option.

• A portion of the circulating water effluent may be used for LNG vaporization.

• Thermal modeling to be performed to confirm no impact on environmentally sensitive areas.

8. Water supply system

• Installing a desalination system to serve as the primary make-up water supply and CT water injection.

• A connection to the city water system will be used as backup.

9. Wastewater & Sewage treatment Systems

• Sanitary waste will be discharged to the local wastewater treatment plant.

• An oily water separator will be used for any waste streams coming from potentially contaminated areas.

• All process water collected on site, including effluent from the oily water separator, will be treated by a wastewater treatment system and re-used.

• Oil collected in the oily water separator will be pumped out and disposed of off-site.

• A false start drains tank will collect liquid fuel resulting from an unsuccessful combustion turbine start on diesel. This waste will be disposed of off-site.

• Combustion turbine off line water wash waste will be collected and disposed of off-site.

• Purge water from the performance fuel gas heater will be collected and sampled to determine whether there is hydrocarbon contamination. Uncontaminated water can be processed in the wastewater treatment plant and re-used. Contaminated water will be disposed of off-site.

10. Fire protection

• An inert gas system (CO2) will protect the combustion turbine compartments.

• Sprinkler systems will be used to protect the turbine areas, control room, and other sensitive electrical rooms.

• A motor driven fire pump and backup diesel driven fire pump will be provided.

• A combined raw / fire water storage tank will be used as the primary fire water source.

• Standpipes inside the fire tank for raw water use will ensure a dedicated fire water source.

• An additional dedicated fire water tank will be provided to serve as a backup fire water source if the city water source does not meet NFPA reliability requirements.

• A ring header around the site with fire hydrants will be used for general site protection.

11.Fuel supply

• Liquid fuel usage rate is 1,367 l/min per combustion turbine at base load. This assumes a diesel heat content of 42.33 MJ/kg (LHV) @ 25oC.

• Bulk storage facility will have 6 tanks each sized at 47.7 million liters, each to provide 21 days storage for 6 combustion turbines operating at base load.

• Capacity of the on site diesel storage tank should be 13.5 million liters with a usable capacity of not less than 11.8 million liters, assuming 6 CTs operating at base load for 24 hours.

• Two 160,000 m3 LNG tanks with a third tank in the future are assumed.

• LNG terminal availability will be assumed at 98%

Site Layout

C. LNG Integration

C. LNG Thermal Integration

• LNG-CCGT Thermal Integration will be evaluated. Following options will be studied.– Cooling water integration

– Gas turbine inlet air chilling

– Base case – no integration.

– As back-up both open rack vaporizers (ORV) and submerged combustion vaporizers (SCV) will be considered.

D. Project Milestones

D. Project Milestones

• 28 July 06 – Specs for long-lead items• Sept 06 – Concept Design / Prep EPC Specification

complete• Oct 06 – EPC Bid Issue• Jan 07 - Submit bids• 15 April 07 – EPC LNTP Award• 31 May 07 – Prelim EPC Design complete• 31 Aug 07 – ROD/EPC NTP award• Mid Sept 07 – Start construction• 01 Feb 08 – Start foundations• 01 Aug 08 – Port available

D. Project Milestones (continued)

• 30 Nov 08 – Tank farm complete• 01 Jan 09 – Diesel available• Mid April 09 – Backfeed• Mid May 09 – First Fire CT-1• 1st June 09 – First Fire CT-2• Mid June 09 – First Fire CT-3• 01 Sept 09 – Steam blow• 01 Dec 09 – Planned commercial operation (CC)• 01 March 10 – Guaranteed commercial operation (CC)