Optimal Selection and Economical Ranking of Isolated Renewable-based CHP Microgrid in Cold Climate, a Case Study for a Rural Healthcare Center

Rural Health Centers (RHCs) are nationally crucial points of interests, requiring electricity to continue storing drugs, offering health services, performing minor and outpatient surgeries, and other health services under any circumstances. With outbreaks such as COVID-19, constant power supply has become a challenging endeavor in Iran craving more attention. Accordingly, this research aimed at finding an optimum combined heat and power (CHP) system using renewable energies (wind, solar, and animal biomass) for the first time in a RHC in Iran. Different hybrid scenarios were evaluated and ranked in HOMER v2.81. The techno-economic-environment-energy performance of vortex turbines were assessed, for the first time, and were then added to the software database. The results showed that the top three scenarios are solar cell-battery (first scenario), solar cell-biomass-battery (second scenario), and solar cell-wind turbine-battery (third scenario) with levelized cost of energy (LCOE) of 0.393, 0.406, and 0.468 $/kWh, respectively. In the top economic scenario, 25% of the required energy was generated by solar cells and the rest by gas boiler that producing 7,050 kg of CO2 annually. In the third scenario, the most environmentally friendly one, CO2 was reduced by about 60 kg compared to the first scenario. Another important point is the important role of dump load in converting excess electricity into heat, contributing to 20% of the generated heat in the first scenario. Based on the results, the authors suggest focusing on solar energy in the studied region given its higher economic potential than wind and biomass energies.