摘要
A systematic techno-economic analysis of geothermal assisted power generation (GAPG) was performed for a 500 MW unit of a typical coal-fired power plant located at the upper Hunter region of New South Wales, Australia. Specifically, the GAPG viability and performance was examined by investigating the impacts of reservoir temperature, resource distance, hybridisation scheme, and economic conditions including carbon tax and Renewable Energy Certificates (REC). The process simulation package, Aspen HYSYS, was employed for all simulation purposes. Thermodynamically, GAPG system was found to increase the power output of the plant by up to 19% under the booster mode whilst in fuel saving mode the coal consumption reduced by up to 0.3 million tonne/year decreasing the Green House Gas (GHG) emission by up to 15% (0.6 million tonne/year). Economic analyses showed that for a typical HDR resource with a reservoir temperature about 150 掳C located within a 5 km radius from the power plant, the GAPG system becomes economically competitive to the stand-alone fossil fuel based plant when minimum carbon tax and RECs rates of 40 $/tonne and 60 cents/kW h are introduced. The figure of merit analyses comparing GAPG system with both stand-alone fossil fuel and stand-alone geothermal plants showed that an economically feasible GAPG system requires the use of HDR resources located no further than 20 km from the plants. Reference maps were also developed to predict suitable conditions for which the hybrid plant outperforms the stand-alone plants.