A victim of its own success, Busway line 4 attracts higher ridership than Semitan expected, pushing the system to saturation.

Semitan tested the Hess LighTram in November 2009 to eventually increase capacity of the system and relieve overcrowding at peak times.

[3] Such saturation in Nantes would imply that a bottleneck such as the number of landing areas at a crowded busstation[4] could not be opened up, because without any bottleneck peak buses, frequency per hour per direction for instance in BRT Belo Horizonte corridor Antônio Carlos was 500 in the year 2014[5] and 600 buses in BRT Rio corridor Presidente Vargas[6] compared to 20 (in the year 2008) in Nantes.

Instead of the planned Tramway line Nantes preferred the e-bus HESS lighTram 25 TOSA combined with ultrafast charging (later HITACHI), which started operation in August 2019.

[7] In February 2022 the International Association of Public Transport (UITP) awarded the HESS e-bus system with HITACHI ultrafast charging in Nantes for "operational and technological excellence".

Semitan issues a wide range of monthly and annual passes for different categories of travellers depending on their age and working conditions.

Semitan also sells monthly, termly and annual Lila, Métrocéane and Pratik+ passes, for several categories of persons depending on their age and working conditions.