With the development of smart grid and internet of things, more systems can improve the intelligent community, such as intelligent electricity, distributed clean energy and electric vehicles etc. These intelligent community systems generate massive data. In this paper, we carry out various power big data applications and integrate the cloud computing technology and business intelligence to build a novel business intelligence system. Meanwhile, based on Hadoop, HBase, Hive etc., we realize the ETL, OLAP, data mining and BIReport functions. Also we present a novel parallel algorithm to achieve the data mining algorithms and data analysis algorithms, and solve the issue of processing speed of large-scale data analysis. We have deployed the business intelligence system in Gansu Province, Beijing, Shanghai and other areas of China, where good results have been achieved. In terms of energy efficiency, it can save more than 8% costs, while increasing the functions of the intelligent community, and realize the intelligent life preliminarily.