We have developed an efficient two-stream auroral electron model to study the deposition of auroral energy and the dependence of auroral emission rates on characteristic energy. This model incorporates the concept of average energy loss to reduce the computation time. Our simple two-stream model produces integrated emission rates that are in excellent agreement with the much more complex multistream model of Strickland et al. (1983) but disagrees with a recent study by Rees and Lummerzheim (1989) that indicates that the N2 second positive emission rate is a strongly decreasing function of the characteristic energy of the precipitating flux. Our calculations reveal that a 10 keV electron will undergo approximately 160 ionizing collisions with an average energy loss per collision of 62 eV before thermalizing. The secondary electrons are created with an average energy of 42 eV. When all processes including the backscattered escape fluxes are taken into account, the average energy loss per electron-ion pair is 35 eV in good agreement with laboratory results. ¿ American Geophysical Union 1990