High-speed moving vehicles can produce strong wakes which contain considerable amount of localized wind energy. Previous studies have proved the feasibility of using vertical axis wind turbines (VAWTs) to recover energy from the wake of vehicles on highways. However, two key problems remains unsolved considering the highway wind turbines. What is the best type of VAWTs for highway wind energy recovery? And what is the best gap between VAWTs if they are planted in an array? This study aims at solving the above two problems using three-dimensional computational fluid dynamics (CFD) simulations. First, the performance of three different rotors are evaluated and compared, it is found that the Banki rotor operates best in the wake of a moving vehicle. Then, simulations are performed on an array that composed of three Banki rotors. The performances of the array is evaluated at different rotor gaps and the optimal rotor gaps are provided for different situations. (C) 2019 Published by Elsevier Ltd.