In the article, a study of conversion of energy in a hybrid (electro-hydrostatic) drive of a utility van intended for city traffic is described. In this hybrid drive, the electric drive is periodically accompanied by hydrostatic drive, especially during acceleration and regenerative braking of the vehicle. We present a mathematical model of the hybrid drive as a set of dynamics and regulation equations of the van traveling at a given speed. On this basis, we construct a computer program, which we use to simulate the processes of energy conversion in electro-hydrostatic hybrid drive. The main goal of the numerical simulation is to assess the possibility of reducing energy intensity of the electric drive through such a support of the hydrostatic drive. Our results indicate that it is possible to significantly increase the efficiency of energy conversion in the electric drive by support of the hydrostatic drive. In the article, chosen results of simulation studies for multiple starting and braking the car are given, and they show a 30% decrease for energy drawn by the hybrid drive, compared to solely electric drive.