The thermal inertia of buildings and the uncertainties in a microgrid have an important impact on the optimal operation of the microgrid. To research the microgrid with combined heating and power（CHP） system

a mathematical model of the micro-sources and heating thermal inertia model was established firstly. Moreover

the uncertainty of renewable energies power and load power was described by using interval mathematics method. On this basis

an optimal scheduling model based on interval multi-objective linear programming（IMOLP） was established. In this model

the economic cost and environmental cost of microgrid operation were minimized for multiple objectives

the influence of uncertain factors in microgrid was considered

the heat dissipation of radiator was added as a control variable

and the traditional thermal load balance constraint was transformed into indoor temperature that meets the comfort requirements of human body. Then

combined with the time-sharing electricity price

the Cplex optimization software was combined with the MATLAB programming to achieve the IMOLP method. The results of examples show that the multi-objective optimization model can achieve good environmental benefits while reducing economic costs

and effectively deal with uncertainties in microgrids.