Study of 2000 UVIS FUV spectra with hydrocarbon and Lyα/H2 methods and 2 polar atmospheres. Mean primary electron energy mostly between 1 and 17 keV. Energy flux - mean energy correlated: plasma characteristics compatible with electron temperature near 0.1 keV and density near 3 × 103 m−3. Lyα/H2 method allows calculation of electron energy maps. First statistical maps of the auroral electrons mean energy show clear local-time dependence.