Measurements of multi satellites and geomagnetic indices are used to investigate the energy budget during an isolated substorm. The calculation of the energy transfer from the solar wind to the magnetosphere (parameter ε ), the energy increase of the ring current ( U R ), the Joule heating ( U J ), the particle precipitation energy flux ( U A ) and their time-integrated energy dissipation W ε , W R , W J , W A indicates that there should be energy dissipation such as plasma heating and the energy returned to the solar wind by plasmoid ejection from the tail. After calculating the spatial sizes of nine selected BBFs, the energy flux density and energy transported Earthward or tailward by BBFs, using observations from three satellites, are found to be different during an isolated substorm. The flow thermal energy is dominant whether the energy is transported Earthward or tailward under the frozen-in condition in the inner plasma sheet. From results simultaneously observed by three satellites in the magnetotail, we find that the Earthward energy transported by the flows can provide the energy dissipation of W J and W A , where the flows are Earthward for more than 60% of the samples, while the tailward energy transport is far larger than U A and close to U J , where the flows are tailward for less than 40% of the samples. The maximum energy flux density is observed by one satellite to be accompanied by large variations, while the maximum energy transport is observed by another satellite with large energy flux density and small variations. This suggests misleading conclusions would be obtained if there were only data from single (or two) satellites. From our results, BBFs play an important role in the process of energy transport both Earthward and tailward during this isolated substorm. Data based on observations from one satellite in the magnetotail could be easily misinterpreted and should be used cautiously.