The big data computing is one of the researches focus in the Cloud Computing nowadays. With the development of electric power information, the business complexity continues to increase and the amount of data is increasing quickly which makes the traditional way of computing be worse and worse. This paper provides an effective computing of big data base on the Objectification Parallel Computing (OPC) to solve the above challenges. The small data set is split from Big Data, is distributedly stored in memory of OPC Cluster. In the effective compute server, making use of the thought of divide and rule and tree merging, there are two stages. The first stage is local data calculate. The intermediate calculation result can be obtained. The second stage is multistage summarizing. The final result can be returned to user. The solution has been applied to the power production management system (PMS) of State Grid of China. The results show that solution is efficiently reliable and meets users' requirement.