The investment cost for a BRT(1) system is between €4 million and €10 million per kilometer of infrastructure, compared with between €15 million and €35 million for light rail.
On a practical level, BRT provides the same capacity, speed and accessibility as light rail but with the added advantage of flexibility: it can travel on all roads, whereas light rail is limited to its rail track.
Current experiments with automated control will also earn this system additional point. The optical guiding system implemented in Rouen, France, and Las Vegas, United States, allows the vehicles to dock closer to platforms, thereby improving bus accessibility, which is particularly useful for people with special needs. This system is based on an onboard camera and ground markings that act like a virtual rail, and an electric motor that takes over control of the bus as it approaches stations. The driver remains in control of acceleration and braking, and can regain control of the bus at any time by touching the steering wheel.
The most recent innovation is radar telemetry to detect obstacles. Installed experimentally on a bus, this equipment will be integrated into the assisted driving system and will improve speed profiles by factoring in any obstacles in the vehicle's path.
(1) Bus Rapid Transit