The importance of accuracy and reliability of the systems of power accounting metering information is emphasized in the article. Various mathematical methods of bad data identification are examined. Position of the method relative to the state estimation is the basis for methods separation into different types. Special attention is paid to the a posteriori bad data analysis. Applying of energy flow problem to reveal measurements with errors which exceeds admissible limits is described. In contradiction to traditional state estimation, energy flow problem variables are flows of energy. Test case is calculated to demonstrate the efficiency of the method.