The work is about energy demand assessment for long term operation of vehicles in everyday conditions, with mileage measured in thousands of kilometers over a period of several years. This is in opposite to short-term tests - now WLTP and RDE or various specialist tests). The work concern mainly battery electric vehicles (BEVs). The assessment of their long term energy demand, from presented point of view, is new. Therefore, there is difficult to find published papers for direct discussion.
For describing the energy need was the theory of cumulative energy demand applied. The theory was earlier for assessing the cumulative fuel consumption (for classic and hybrid cars) used.
This theory proved very useful here. Very good adequacy of mathematical models was obtained.
It is proposed the cumulative energy demand, intensity of this demand and "energy economy", together as an vehicle's "energy footprint" understand.
The results obtained seem interesting. The cumulated energy need increases as the mileage increases, but the increase is not linear.
The discrepancies between the energy demand in the vehicle group, the same brand and type, are large and increase as the mileage increases.
The average energy demand of (analyzed) BEV's in long-term operation exceeds (significantly) what is determined in short tests, e.g. WLTP.
It seems important that if the energy demand for long term operation is known (also as prognosis) and the energy sources (energy mix) also known is, then possible is the real emissions (for example CO2) from BEV's operation to estimate.
The presented here examples results leading to conclusions, which are rather not welcome.
If electric vehicles are charged from public energy networks, e.g. in the EU, and the energy mix in particular countries into account taken is, then using BEV’s in some countries is verified while in others it may lead to an (unjustified) increase of CO2 emissions.
it is necessary to consider whether, in addition to the rapid implementation of e-mobility, the appropriate changes in the energy sector should not be implemented even faster.