Damghan city is an area in Iran that has the suitable potential for energy supply by renewable energy. The average wind speed for Damghan is 3.54 m/s, and solar radiation is 7.8 (h/d) that it shows good potential for energy supply. In this paper, four different models of hybrid renewable energy systems with a combination of photovoltaic panels, wind turbine, and diesel generators are investigated for residential application in Damghan city. Simulation, optimization, and modeling procedures are done by HOMER software. From the technical view, this study shows that among three hybrid systems investigated, PV-wind system has the highest value of electrical production with 18,478kWh/yr and the PV-diesel system has the lowest value of electrical production with 9,876kWh/yr. Moreover, from the environmental view, the PV- Diesel system is highest with 2,402 kg/yr and the PV-wind system has the lowest pollution rate, i.e., 0%. These results show that long-term planning for investing in renewable energies is proper for this city.Abbreviation: NPC: Net present cost; : Capital recovery factor; k: Shape Parameter; COE: Energy cost balance; c: Scale Parameter; : Power panel; NOCT: Normal Operational Cellular Temperature; : Ambient temperature; : Rated power of the wind turbine; : Cut-in wind speed; f: The function of the Weibull distribution;: Rated wind speed; : Cut-out wind speed; : Coefficient of performance; A: Swept area; : Wind speed; : Air density; : Reference module efficiency; A (m): PV generator area; G (t): Solar irradiation in tilted module plane; G: Solar irradiation; : Solar radiation at a standard temperature condition; : the temperature at reference conditions; : The temperature coefficient of the PV module; : Ambient temperature; : Potential voltage; : at standard condition (V); :Panel's current at standard condition; : Short circuit current at standard condition; Open circuit (V/degrees c) temperature coefficients; : Wind speed at height of h; : Wind speed at height of ; :Fuel quantity; H: Fuel heating value (MJ/L); : Total annual cost (in dollars); C: Carbon emission factor (ton carbon/TJ); : Oxidized carbon fraction; I: Nominal interest rate; n: Number of years; E-is: Electrical energy; E-grid: Amount of electricity sold to the grid; tCO(2): Amount of CO2 emissions; : Temperature at standing operational condition; T-c: operationaltemperature of panel.