Mumbai, May 30 -- Marking the second increase in less than a fortnight, Mahanagar Gas Ltd (MGL) announced a Rs.2 per kg increase in compressed natural gas (CNG) rates. The revised rates will come into effect from the midnight of May 29-30, while domestic piped natural gas (PNG) prices will also rise by 50 paise per standard cubic metre (SCM). The hike has triggered fresh demands from auto-rickshaw and taxi unions for a fare revision. The latest revision takes the retail price of CNG to Rs.86 per kg from Rs.84 per kg. Domestic PNG will now cost Rs.52 per SCM in Mumbai, Thane, Navi Mumbai and adjoining areas under Mahanagar Gas Ltd. The hike is expected to affect nearly 12 lakh CNG-powered vehicles in the Mumbai Metropolitan Region (MMR), including around 2.8 lakh auto-rickshaws. The previous increase came into effect on May 13-14. According to MGL, the consecutive hikes were necessitated by a sharp increase in gas procurement costs. "Due to a significant increase in gas procurement costs caused by reduced allocation of domestic gas, increased dependence on higher-cost gas sources, and depreciation of the Indian Rupee, the overall cost of gas has risen considerably," sources in the MGL told Hindustan Times. The fresh increase has reignited demands from auto-rickshaw and taxi unions for a fare revision. Mumbai Rickshawmen's Union leader Thampy Kurien said the increase in gas prices has led to a fresh calculation as per the fare hike formula. "The formula, which takes into account the rising fuel rates, shows a need for a fare hike of around Rs.1.12 per km on the base fare, which is rounded off to a rupee fare hike," Kurien said. Officials said the transport department will forward the proposal to the Mumbai Metropolitan Region Transport Authority (MMRTA), which makes the final decision on auto and taxi fare revisions. Taxi unions have also sought an increase of Rs.2-3 in the minimum fare, arguing that repeated fuel price hikes over the past year have sharply increased operating costs. Union leaders said consecutive CNG price hikes are squeezing drivers' incomes and making it increasingly difficult to sustain operations without a corresponding fare increase. "Drivers cannot absorb these rising fuel costs indefinitely," said another driver. Despite the latest increase, MGL maintained that natural gas remains one of the most economical fuels available. According to company representatives, CNG continues to offer savings of around 45% compared with petrol and about 12% compared with diesel at prevailing Mumbai fuel rates....