In this study, the Micro Grid (MG) formed from the renewable energy resources and the storage battery was analyzed and verified by multi-factors. The target MG power system was planned and installed in Kochi prefecture, Japan and it consisits of wind power turbine and solar power plant as well as micro hydro power generator. The efficiency of a stand alone Micro Grid in reliability and economy as well as environment was assessed. The system reliability is verified by the indices of Loss of Load Probability (LOLP) and Expected Energy Not Supplied (EENS). And the economic efficiency was given appraisal by Yardstick indices of the Net Present Value (NPV) and the Benefit-Cost Ratio (BCR) as well as the Payback Period (PBP). The environment efficiency was evaluated considering the amount of CO2 discharge that was reduced by using installed MG power system renewable energy.