| Abstract |
The Sabalan geothermal power plant in northwestern Iran is planned to produce 50 MW of electricity by 2011 in a cooperative effort of the Ministry of Energy (MOE) and the Renewable Energy Organization of Iran (SUNA). Overall, geothermal energy has been shown to be environmentally acceptable with some positive impacts on climate change mitigation, including a relatively small land-use footprint. EIA process has been already performed (Yousefi et al., 2009). In the evaluation process, the positive and negative environmental impacts of the Sabalan geothermal power plant (GPP) were assessed based on the results of a multi-disciplinary team approach. In this study, an attempt was made to show the contribution of Sabalan GPP to climate change mitigation by reducing CO2 emissions in the area compared to conventional power plants. A network of thirty sampling points and a meteorological station were installed to characterize the air quality and atmospheric transport properties of the area before development. These instruments measured the concentrations of H2S, CO2, SO2, NO, NO2 and particulates. Wind velocities and directions were also measured to determine atmospheric stability. By using these data, the background dispersion model for each gas was prepared in the GIS environment. In the current study, a model was used to predict the distribution of CO2 after utilization of the GPP. To achieve this goal, geothermal steam was analyzed chemically to estimate potential emission rates of air pollutants from the planned 50 MW geothermal power plant. The Industrial Source Complex Model (ISC3View) was applied to make the predictive CO2 dispersion model from the 50 MW planned geothermal power plant into the local atmosphere. The prepared background and predictive model were combined in the GIS environment. The results show that CO2 concentrations will be well below the standard and Kyoto Protocol limits in 98% of the area, and pollutants will be transferred from the power plant to the northeast and east. A maximum CO2 concentration of about 325 ppm was predicted to occur in areas close to the powerhouse. |