In smart grids, demand-side management (DSM) is one of the important function for both customers and utility, since it can reduce the total electricity cost of each customer, meanwhile, alleviate the aggregate peak-to-average ratio (PAR) subjected to real-time pricing (RTP) policy. On the other hand, while bidirectional charging/discharging Plug-in Electric vehicles (PEV) become more general, the capability of storing electrical energy for load shifting may take smart grid to a next level. This works aims at integrating PEV into DSM system, which considers renewable energy and energy trading as well. As it comes to community, we design a fairness strategy to share PEV's battery with neighbors to reduce the total electric cost and peak to average ratio (PAR). The simulation results show that the proposed DSM system not only meets the requirement of the PEV and reduce the cost for each household but also creates a win-win situation through the energy trading among homes based on consideration of both fairness and privacy protection in a residential community.