General Description of the Proposed Coega Integrated Power Project
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CHAPTER 3: GENERAL DESCRIPTION OF THE PROPOSED COEGA INTEGRATED POWER PROJECT GENERAL DESCRIPTION OF THE PROPOSED COEGA INTEGRATED POWER PROJECT CHAPTER 3 CONTENTS 3. GENERAL DESCRIPTION OF THE PROPOSED COEGA INTEGRATED POWER PROJECT _______________________ 3-1 3.1 Overview of the Coega Integrated Power Project _________________3-1 3.2 Description of the proposed project____________________________3-1 3.2.1 LNG berth and terminal _________________________________________3-2 3.2.2 CCGT power plant _____________________________________________3-2 3.2.3 Gas reticulation network _________________________________________3-3 3.2.4 Electricity transmission network ___________________________________3-3 3.3 Location of the proposed project ______________________________3-4 3.3.1 International site selection process_________________________________3-4 3.3.2 National site selection process ____________________________________3-5 3.3.3 Identification of berthing locations within the Port of Ngqura _____________3-5 3.3.4 LNG terminal and CCGT power plant layout options ___________________3-7 FIGURES Figure 3.1: Alternative berth locations for the LNG carriers. ................................................3-6 Figure 3.2a: Alternative site option 1 for the LNG terminal and CCGT power plant.............3-8 Figure 3.2b: Alternative site option 2 for the LNG terminal and CCGT power plant.............3-9 Coega Integrated Power Project: Environmental Screening Study Final Report, February 2004 - Confidential page i GENERAL DESCRIPTION OF THE PROPOSED COEGA INTEGRATED POWER PROJECT CHAPTER 3 3. GENERAL DESCRIPTION OF THE PROPOSED COEGA INTEGRATED POWER PROJECT 3.1 Overview of the Coega Integrated Power Project Under a Joint pre-Development Agreement (JPDA), Shell South Africa Energy (Shell) together with Eskom Holdings (Eskom) and a national gas infrastructure company (iGas), have been investigating the feasibility of developing an integrated LNG to power project within the Coega Industrial Development Zone (IDZ) near Port Elizabeth. This project would involve the following components: A Liquified Natural Gas (LNG) terminal, consisting of a berth with off-loading arms within the Port of Ngqura, cryogenic pipelines, storage and handling facilities and re- gasification modules; A combined cycle gas turbine (CCGT) power plant; Gas pipelines for the transmission, distribution and reticulation of natural gas within the Coega Industrial Development Zone (IDZ) and Port of Ngqura; and electricity transmission lines linking the power plant to the national grid. This proposed project is collectively referred to in this study as the Coega Integrated Power Project (CIPP). 3.2 Description of the proposed project The project is based on the provision of natural gas from an appropriate reliable source, either via pipelines or as a liquid in LNG carriers (LNGC). In the case of the latter, LNG is manufactured at sophisticated facilities near the gas reserves, cleaned and dried, and then cooled to minus 160 degrees Celsius for transport via specially designed LNGCs to an LNG terminal where the LNG is regasified prior to further use. The proposed CIPP would involve importing 2 million tonnes per annum (mtpa) LNG to the Port of Ngqura, regasification and the utilization of 1.5 mtpa in a 1600 MW CCGT power plant, with the remaining 0.5 mtpa being distributed to gas users via a gas reticulation network. The LNG terminal and CCGT power plant are both predicted to operate for a minimum of 35 years. Construction of the LNG terminal and CCGT plant concurrently is estimated to take 3 years, with 2 years required prior to construction for detailed technical design, permitting and authorization, financial closure and investment decisions. From a national electricity perspective, it is important that the CIPP’s phasing correlates to market requirements where additional generation capacity is required from 2007 onwards. Coega Integrated Power Project: Environmental Screening Study Final Report, February 2004 - Confidential page 3-1 GENERAL DESCRIPTION OF THE PROPOSED COEGA INTEGRATED POWER PROJECT CHAPTER 3 CCGT power generation and LNG production, shipping, receiving and regasification technologies are in operation internationally, but do not currently exist in South Africa. Direct investments associated with the CIPP are estimated in the region of US$ 1 billion. The potential exists to expand the facilities, by increasing the gas import up to 5 mtpa or more, for use in increasing power generation capacity up to 3200 MW and gas sales to other markets. 3.2.1 LNG berth and terminal The LNG berth is being designed to accommodate the LNGCs up to 300 m long and 50 m wide, with a maximum draft of 12 m. Based on current assumptions, an LNG off-take of 1.5 mtpa for the CCGT plant will require one LNGC at berth every 16 days (or 23 times per year). Were market off-take to increase this 2 mtpa, one LNGC would berth every 13 days (or 29 times per year). During offloading, the LNG will be transferred in insulated cryogenic pipelines from the berth to the LNG storage tank(s). From there the LNG is sent to vaporization units where the temperature of the LNG is raised in a process to convert the liquid back to gas. Depending on the choice of vaporization technology, this heat can either be drawn from relatively warm seawater or other heat sources such as waste heat from a power plant. Technical integration of a regasification plant with a CCGT power plant could enhance efficiencies in both processes. The key infrastructural components of the proposed LNG terminal are listed below: LNG berth, with offloading arms Cryogenic pipelines from the berth to the on-land storage tanks On-land terminal facilities, including storage tank(s) Regasification plant. LNG berths and activities worldwide are governed by strict safety zones and codes of practice. A safety zone of up to 200 m radius is required around the LNGC manifold offloading arm; or 50 m from the side of the vessel itself. An exclusion zone is also required for 5 m on either side of the cryogenic pipeline. For the on-land facilities, a 200 m radius exclusion zone is required around the LNG vaporisation process area. 3.2.2 CCGT power plant A CCGT power plant uses a composite thermodynamic process and has thermal efficiencies far greater than other generation technology options (Eskom, Shell and iGas, 2003). The availability of seawater for cooling purposes influences the choice of CCGT technology and Coega Integrated Power Project: Environmental Screening Study Final Report, February 2004 - Confidential page 3-2 GENERAL DESCRIPTION OF THE PROPOSED COEGA INTEGRATED POWER PROJECT CHAPTER 3 the proposed 1 600 MW CCGT power plant is based on the ability to abstract approximately 100 000 m3 per hour of seawater. With an LNG requirement of 1.5 mtpa, the CCGT power plant is the anchor user for the LNG supply and import and regasification facilities. The CCGT power plant consists of the following key components: Combined cycle gas turbine Heat recovery steam generators (HRSG) Gas turbines Closed cooling water system. 3.2.3 Gas reticulation network A gas reticulation network from the port is planned, when the market demand increases with the growth of the IDZ. It is planned that 0.5 mtpa of the original 2 mtpa to be imported will be utilized by the gas reticulation network. Gas transfer pipelines will require a servitude approximately 20 m wide. 3.2.4 Electricity transmission network This section is based on discussions with Ronald Marais, Eskom (Transmission) on 27 November 2003. The CCGT power plant will transfer power into the national grid via the Grassridge substation and adjacent Dedisa substation, which are located just outside the IDZ boundary and approximately 10 km north-west of the proposed CIPP site. The design of the configuration of transmission lines within the grid is a complex process, dependent on the increase in power demand in the Eastern Cape, and the timing of when power from the CIPP and/or other generation sources come on-line. At present the amount of power being provided to the Eastern Cape (approximately 1100 MW) is approaching the maximum limit that the existing infrastructure can deliver. However, it is expected that power demand will increase significantly in the next 5 to 15 years. In particular, the NMMM area is predicted to experience a growth in power demand from current levels of approximately 600 MW to in the order of 2000 to 3000 MW, largely as a result of energy intensive industrial developments located within the Coega IDZ. This will require additional power generation capacity, which could partially be met by the proposed CIPP. The source of power therefore influences the transmission line configuration. A further factor that has to be considered is that the CIPP needs adequate “release” lines, i.e. lines to transmit to the power out of the NMMM area, if a major local consumer of power (for example, an aluminium smelter) were to stop drawing power. Coega Integrated Power Project: Environmental Screening Study Final Report, February 2004 - Confidential page 3-3 GENERAL DESCRIPTION OF THE PROPOSED COEGA INTEGRATED POWER PROJECT CHAPTER 3 Generation of 1600 MW of power from the CCGT plant will require three 400 kV transmission lines from the plant to the Grassridge substation. Transmission capacity from the Poseidon substation (near the town of Cookhouse) to Grassridge is currently being increased, with a third line to be constructed from 2005. Poseidon links Grassridge to the central transmission corridor from the highveld to the Cape area. This additional transmission capacity is currently expected to provide sufficient “release” capacity for the 1600 MW plant. If the power generation from the CIPP is increased to 2400 MW, then four 400 kV transmission lines would be required. No additional release lines would be necessary. If power generation is increased to 3200 MW, then a fifth release line would be needed to a new substation which will need to be integrated into the 400kV network.