Stereo-TV observations of pulsating auroral patches have demonstrated that they often consist of thin horizontal luminous layers. By the use of computer simulation it is shown that if the layers derive their energy directly from precipitating energetic electrons, the incident electron beam must either be more energetic than typically observed, have an anomalous non-Maxwellian distribution above 20 keV, or within the thin layer, produce photons at a higher efficiency than in normal collisional energy loss processes. The results could be interpreted as suggesting that the source of energy for the thin pulsating auroral forms is not directly from the precipitation of energetic electrons.