KAI Accelerates Capacity Upgrade for Green Line Commuter Service
PT Kereta Api Indonesia (Persero), together with the Directorate General of Railways at the Ministry of Transportation, is accelerating a capacity upgrade for the Tanah Abang-Rangkasbitung KRL service, known as the Green Line. The effort involves strengthening the electrical system and modernising signalling to reduce passenger density and shorten waiting times.
KAI VP Corporate Communication, Anne Purba, stated that KAI and the Ministry are preparing rolling stock and supporting infrastructure to enable the operation of KRL trains with a 12-carriage formation on the line. A trial for the 12-carriage formation was recently conducted.
Anne explained that reinforcement of the overhead catenary system on the Tanah Abang-Rangkasbitung line has already been carried out. KAI hopes that both the increase in transport capacity and the reduction in headway can be realised this year. The implementation depends on the sufficiency of the traction substations to support a certain number of 12-carriage trains or enable a shortening of the headway.
KAI President Director Bobby Rasyidin previously stated that the high passenger density on the Green Line is influenced by limited infrastructure capacity and available electrical supply. The electrical power on the Tanah Abang-Rangkasbitung line is still at 3,000 volts, whereas the Bogor and Bekasi lines are already supported by a 4,000-volt capacity. This capacity difference means 12-carriage formations cannot yet be operated, leaving transport capacity reliant on 8 and 10-carriage formations.
To address this constraint, KAI will add 11 traction substations on the Tanah Abang-Rangkasbitung line. The additional substations are expected to strengthen the power supply, thereby supporting the operation of 12-carriage trains with greater transport capacity.
Bobby noted that the capacity increase is expected to reduce passenger congestion, particularly during peak hours, while also improving travel comfort for residents in the western part of the Jabodetabek region. The capacity enhancement is being implemented through coordination and synergy between KAI and the Directorate General of Railways as the national railway regulator.
In addition to reinforcing the electrical system, KAI and the Ministry are also preparing to modernise the signalling system. Currently, part of the Rangkasbitung line still uses a closed block system, which limits the number of train journeys on a single operational track. This condition results in a journey headway of around ten minutes. For comparison, the Bogor and Bekasi KRL lines can already serve journeys with a headway of around three to four minutes. By updating the signalling system, line capacity is expected to increase so that trip frequency can be raised and passenger waiting times become shorter. Bobby stated that increasing trip frequency will provide greater flexibility for the public in determining departure and return times.