Abstarct: Sustainable development is a general concept which impact upon almost all aspect of human life like social, economic, environmental sectors and so on. For achieving to this, major alternative is optimal energy consumption. Since greenhouse consumes a significant proportion of energy, consequently it would be important either to represent a practical alternative for energy consumption reduction or to substitute renewable sources for fossil fuel as much as possible. In this thesis, with the aim of expansion of the use of renewables, different climates are chosen and then it is investigated thoroughly which type of renewables would be suitable for each climate. Simulation, optimization and greenhouse’s cooling and heating load calculation of are implemented in Design Builder software. In the next step, after simulation of existing condition, the use of renewables such as solar energy combining with CHP systems in order to supply load for greenhouse is examined. Homer software is used for renewables simulations. Finally it is obtained for optimization that it is not economically profitable to use solar energy combining with a CHP system in climates of Tehran, Sari and Tabriz. Because of high cost of energy coming from a solar system; on the contrary the low cost of fossil fuel in Iran, the use of the combination of solar and CHP systems is practically feasible only in Bandar Abbas. In the Climates such as Tehran, Sari and Tabriz is proposed to generate energy only by CHP systems so as to be economically acceptable. Also, regarding to optimization results, 4.1KW solar panel and 140KW generator are suggested for Bandar Abbas. However, 70 KW, 80 KW and 100 KW generators are suggested to be sutible for Sari, Tabriz and Tehran, respectively.