CHENNAI: Metropolitan Transport Corporation (MTC) will convert 240 of its diesel-run buses into compressed natural gas (CNG) vehicles as part of the transport department’s initiative to convert 1,000 buses into CNG vehicles.
Of these, 120 will be assigned to the Ambattur depot, while the remaining are designated for the upcoming Varatharajapuram depot near Mudichur along Outer Ring Road, which is yet to be constructed. Both depots will operate exclusively with CNG-powered buses.
To support this transition, MTC has signed Memorandums of Understanding (MoUs) with two city gas distribution companies -- Think Gas and Torrent Gas. Think Gas will develop the necessary CNG infrastructure at the Varatharajapuram depot, while Torrent Gas will handle CNG supply at the Ambattur depot. Each company is also responsible for establishing refuelling facilities within the respective depots.
T Prabhushankar, Managing Director of MTC, told TNIE that under the MoUs, the price of CNG will be fixed at a 6% discount on the diesel landing cost. “For example, if diesel is priced at Rs 90.65 per litre, the corresponding landing cost would be Rs 85.20. This figure will serve as the base rate for purchasing CNG for the first six years of the 15-year agreement. As a result, MTC will be able to procure CNG at a rate lower than the retail market price,” he explained.
The CNG refuelling stations will include two segments: one exclusively for MTC’s use and the other as a retail station for highway and road users. MTC will earn rental income from leasing land to the gas suppliers. Tenders for the construction of the Varatharajapuram depot are expected to be issued soon, Prabhushankar added.
A pilot study conducted by Pallavan Transport Consultancy Services (PTCS), the technical wing of the transport department, revealed that three retrofitted MTC buses running on CNG achieved savings of Rs 2.9 to Rs 3.5 per kilometre compared to diesel. The initiative, originally conceived by former transport secretary K Phanindra Reddy (who retired on Thursday), aims to significantly reduce operational costs, which have contributed to mounting debts across transport undertakings.
A broader study involving 40 CNG-converted buses across eight transport corporations showed CNG buses achieving fuel efficiency of 6.1 to 7.1 km per kg, compared to 4.21 to 5.96 km per litre for diesel buses.
According to official estimates, the cost of converting a diesel bus to run on CNG ranges between Rs 7 lakh and Rs 8 lakh. Mofussil buses are expected to recover this investment within 9 to 10 months, while town buses may take 13 to 14 months. Only buses with a remaining operational life of five to seven years will be eligible for conversion.