Simulation and performance analysis of the new geothermal co-generation power plant (OV-5) at Svartsengi, SW-Iceland

Abstract

The modular method is used to simulate and analyse the performance of the new co-generation power plant (OV-5) at Svartsengi that generate electricity via a single-flash process and supplies turbine's extraction steam to heat exchangers where fresh water is heated up to 110°C for a district heating system. The utilization efficiency of the power plant is improved by 15%, using extraction steam instead of high-pressure steam and it is 14 -22% at different heat loads. The turbine model shows that at 24 MWe electrical output and the rated heat load, the pressure of the first and the second extraction drops below 2.5 bar-a and 1.3 bar-a, respectively. At this point, it is necessary to supply high-pressure steam to heat exchangers. The optimum main steam pressure for the turbine is 5-7 bar-a in order to maximize the power output and limit the exhaust wetness to 12-13%.