Delhi’s air pollution falls in the category of “severe to emergency” with the Air Quality Index (AQI) for particulate matter (PM) hovering between 360 and 500. For a good AQI, a rating of 0-50 is required, which is hardly ever witnessed in the capital due to high emissions from vehicles, factories, etc. To bring down emissions, the Delhi government has been taking several measures pertaining to the transport sector.
Some of these are the introduction of BS-IV norms, an increased focus on electric and hybrid vehicles, and a shift to cleaner fuels. While vehicles are already being run on cleaner fuels such as compressed natural gas (CNG), the Supreme Court has now pushed for the use of a futuristic fuel called hydrogen-enriched compressed natural gas (H-CNG) to curb pollution further. Initially, the fuel will be pilot tested on around 50 CNG buses in the city. With this, Delhi will be the first city in the country to witness the roll-out of H-CNG buses for public use.
Piloting clean fuel
In August 2018, the Supreme Court directed state-owned Indian Oil Corporation Limited (IOCL) to take up a pilot project on public buses to assess the use of H-CNG to facilitate the transition to cleaner fuels. To this end, in July 2019, IOCL, in collaboration with Indraprastha Gas Limited, laid the foundation stone for the first H-CNG production unit at Rajghat Depot 1 of the Delhi Transport Corporation (DTC). The unit, which stands completed, will produce 4 tonnes of compact reformer-based H-CNG for DTC buses every day. After the commissioning of the unit, the fuel will be pilot tested on around 50 BS-IV-compliant CNG buses for about six months to check its feasibility. The trials will be conducted by Anthony Road Transport Limited, which has been selected as the concessionaire for the cluster scheme.
H-CNG is a futuristic fuel, which is produced using the compact reforming process wherein hydrogen-enriched CNG is prepared not by physically blending hydrogen with CNG but by spiking hydrogen in CNG. The technology has been patented by IOCL.
According to a report by the Environment Pollution (Prevention & Control) Authority (EPCA), the gas compact reforming process will partially reform the natural gas to provide a hydrogen-CNG mixture with 18 per cent hydrogen. The process is flexible as the machine can be installed at the location where the gas is available and allows for the production of H-CNG based on demand. The fuel can then be compressed for direct use in motor vehicles and help reduce carbon monoxide emissions by at least 70 per cent and hydrocarbon emissions by 25 per cent. It is estimated that this compact reforming process is 30 per cent more cost effective as compared to the physical blending of hydrogen in CNG. According to the EPCA, the technology is extremely promising as it can be deployed in different locations, including at petrol pumps and bus depots. Moreover, it allows for the utilisation of Delhi’s existing CNG infrastructure, which comprises around 5,500 CNG buses.
So far, countries such as the US, Canada, Brazil and South Korea have conducted H-CNG trials. If the project is smoothly executed in the capital, Delhi will become the first Indian city to join the league of global cities using H-CNG. However, to fuel the existing fleet of around 5,500 CNG buses, around 400 tonnes of H-CNG will be required on a daily basis. For this, the setting up of four production plants of 100 tonne capacity each has been recommended. A capital investment of around Rs 3.3 billion will be required for this purpose. Moreover, H-CNG is rather expensive as compared to CNG, by an estimated Re 0.75 per km. However, the social benefits that it will bring to the city cannot be overlooked given the high levels of pollution. The Supreme Court has also pushed for a shorter time frame for enabling a faster switch to H-CNG. To make this transition smoother, timely approvals and setting up of stations will be key.