Authors: K.M. Hardiman, B. Seyedan, R. Hynes and G. Delfs
ASME Asia Pacific Conference in Bangkok, October 5th 2009
Abstract
Australia’s commitment to the Kyoto Protocol to tackle climate change problems mandates the need for transforming the power industries to favouring more renewable energy sources to reduce specific greenhouse gas emissions. Sharing a similar vision, Hatch and Acquasol Infrastructure Ltd (Acquasol) carried out the design study of an integrated Solar / Combined Cycle Gas Turbine (CCGT) power plant to provide a minimum of 100 MWe base load power continuously (excluding maintenance periods). The proposed plant consists of a combined nominal output of 180 MWe, of which 30 MWe will be contributed by solar power. The solar farm consists of a large field of single-axis-tracking parabolic trough collectors, covering an area of 1,300 m x 650 m, with a capability to generate superheated steam at 380ºC. The solar steam is integrated into the steam cycle of the CCGT plant via specially-designed HRSG units, in lieu of adding steam flow directly into the steam turbines. In view of redundancy requirements, the power plant was designed with two parallel trains with each train consisting of 2 sets of 25-MWe Gas Turbines and HRSGs connected to a 40-MWe Steam Turbine unit via a common steam header. A proportion of steam generated is directed to a Multi Effects Desalination (MED) unit for flashing seawater to produce desalinated water. The MED unit was designed to be able to deliver 10 ML/d of fresh water for on-site usage with the remainder to be sold to the local water network. The seawater intake for the desalination plant is approximately 31 ML/d. For 8 to 10 months in a year, the brine discharge from the MED unit will be sent to the adjacent salt fields as feedstock to the salt making process, thereby minimising emission to the environment. The Acquasol project demonstrates that the integration of proven technologies into single project
(solar power, CCGT and MED) is able to deliver considerable cost, efficiency and environmental benefits.
