Intelligent buildings are the trend of future buildings, as well as, micro-grids are important scenarios of smart grid under going. An intelligent building integrated with micro-grid can fit the much comfort and low energy consumption targets better. However, the output power of micro-sources in the micro-grid for intelligent building application is stochastic, uncertain and uncontrollable. Thus, micro-sources design of an intelligent building integrated with micro-grid is a significant issue. Therefore, a mathematical model is proposed to optimize the capacities of micro-resources, which can harvest green energy from renewable energy resources (RERs) as much as possible. In the presented model, energy cost coefficient (ECC) is set as the minimization objective function, F, which is defined as the ratio between energy cost of intelligent building and the output energy of RESs. It is should be noted that ECC is different from conventional optimum objective to minimize the cost of whole project, C. As a result, a multi-objective model associated with F and C is also discussed to satisfy different requirements and targets of numerous users. A numerical example is utilized to validate the feasibility of the proposed approach. Simultaneously, the Pareto fronts of the multi-objective model are obtained using Linear INteractive and General Optimizer (LINGO). Crown Copyright (c) 2012 Published by Elsevier B.V. All rights reserved.