  Mobility is an indispensable part of modern human societies, but the
dominance of motorized individual traffic (MIV, i.e., the private car) leads to
a prohibitive waste of energy as well as other resources. Here we show that by
combining a line service (e.g., railway) system with a fleet of ride-pooling
shuttles connecting line stops to desired pick-up and drop-off points, a
bi-modal public transport system may result which provides on-demand
door-to-door service at a service level (in terms of transit times) superior to
current public transport, and with an overall comfort level comparable to MIV.
We identify the conflicting objectives for optimization, i.e., user convenience
and energy consumption, and evaluate the system performance in terms of Pareto
fronts. By means of simulation and analytical theory, we find that energy
consumption can be as low as 20% of MIV, at line service densities typically
found in real settings. Surprisingly, we find favorable performance not only in
urban, but also in rural settings.
