Feasibility study on simultaneous generation of electricity and heat using renewable energies in Zarrin Shahr, Iran

The increasing urban population and incorrect patterns of urban activities along with inappropriate development of cities have incurred significant damage to the environment and have faced man with numerous problems such as fossil fuels deficiency. The environmental problems owing to fossil fuels and increasing demand for energy have made the approach to renewable energies and the development and utilization of these sources more and more necessary. The development and promotion of renewable energies aid the realization of countries' developmental goals in economic, social, and environmental aspect which is one of the basic factors in achieving sustainable development in any country. Biomass is one of the sources that no acceptable assessment of its technical-economic production feasibility has been done yet in various regions of Iran. Biomass is of considerable importance among renewable energy resources and its usage in energy generation prevents pollution caused by its discharge into the environment along with generating clean energy similar to that obtained from other renewable sources. Since biomass is not well known as a source of energy generation in Iran and because there are no clear regulations concerning its use for this purpose, this paper used the HOMER software to study four scenarios of utilizing wind, solar, and biomass energies for the simultaneous generation of electricity and heat in ZarrinShahr located in Isfahan Province. Results showed that receiving electricity from the national grid is superior to the use of biomass if the under study place is less than 2.58 km away from access points to this grid. Otherwise, based on economic optimization performed by HOMER software, it is recommended that a hybrid system of renewable energy including a solar panel, a biomass-fuelled generator, two batteries and a converter at a cost of 1.019 $/kWh be used, in which 1955 kWh is generated by the solar panel and 92 kWh by the biomass-fuelled generator. According to the study of previous researches, no reviews have been made thus far on the use of dump load for the provision of electricity and heat in hybrid renewable energy systems.