  Shift of the power system generation from the fossil to the variable
renewable sources prompted the system operators to search for new sources of
flexibility, that is, new reserve providers. With the introduction of electric
vehicles, smart charging emerged as one of the relevant solutions. However,
electric vehicle aggregators face the uncertainty of reserve activation on one
side and electric vehicle availability on the other. These uncertainty can have
a negative effect on both the aggregators' profitability and their users'
comfort.State-of-the art literature mostly neglects the reserve activation or
the related uncertainty. Also, they rarely model European markets or use real
balancing data. This paper introduces a new method for modeling the reserve
activation uncertainty based on actual data for the European power system.
Three electric vehicle scheduling models were designed and tested: the
deterministic, the stochastic and the robust one. The results demonstrate that
the current deterministic approaches inaccurately represent the activation
uncertainty and that the proposed models that consider uncertainty, both the
stochastic and the robust one, substantially improve the results.
