Smart energy farm targets large cities suffering from the deepened urbanization. To cope with the problems of urbanization, more renewable energies such as free cooling etc. are going to be connected to the energy network in the city. The building farm will provide food self-sufficiency, urban green space, and healing space. A micro energy network, which enables two-way energy trading, will also be connected with the participation of energy prosumers. In addition, It will greatly reduce the use of fossil fuels by taking advantage of the large amount of waste heat generated in large cities. Moreover, carbon recycling technology such as power to gas and its relevant variants model in the form of hybrid farm will greatly mitigate the effects of climate change through the convergence with IOT technology.