The (relative) grain boundary energy of random high angle boundaries has been measured in several Fe-based polycrystals. Crystallographic data obtained by orientation contrast microscopy (OIM) are combined with the geometrical configuration of grain boundaries at triple junctions. A two-parameter representation of the relative grain boundary energy in terms of misorientation angle and misorientation axis is presented. In the applied procedure a variation of the energy values assigned to one boundary was observed depending on the triangulation path chosen by the operator to connect the arbitrary initial boundary with the boundary under consideration. Results show no evidence of correspondence between the observed energy cusps and the presence of CSL boundaries.