Electrification of regional railways is a promising strategy to reduce greenhouse gas emissions and improve air quality. While overhead line equipment is viable for high-traffic routes, battery-electric trains offer a cost-effective alternative for low-traffic corridors. However, large onboard batteries pose challenges, including high costs and environmental impacts. This study explores shared charging infrastructure for rail and road vehicles, combining static and dynamic charging. Simulations show that distributed static charging reduces battery size, emissions, and costs, while dynamic charging offers further benefits but requires higher investment.