Abstract: Home energy management systems (HEMS) can properly schedule domestic appliances and minimize the electricity purchasing costs. However, single HEMS limits load regulation ability, and it is hard for it to fully consume solar output. In this paper, an energy management system model is proposed, which involves multiple family clients. Load aggregator (LA) coordinates the power consumption of multiple families so that the electricity purchasing costs of families are minimized. At the same time, the LAs achieve their benefits, which verify the feasibility of proposed model. The comparison of different cases shows that proposed model can consume more local PV power, and reduce customer's electricity purchasing cost.