CNG Bus Fleets for a Cleaner Urban Air

With more and more of the world’s population living in cities, urbanisation is a growing global trend. As cities grow larger and larger, huge amounts of energy and resources are required to keep people happy and comfortable. This has created an incredible amount of waste, dangerous by-products and pollutants. The resulting air pollution endangers not just human lives but the existence of our planet itself.
CNG Bus Fleets Avert a Dangerous Urban Future: A 2012 report by the Organisation of Economic Cooperation and Development (OECD) paints a frightening picture. The report states that ‘dirty air will kill more people worldwide each year than drinking water or unsanitary living conditions,” and emphasises that urban pollution will be the top environmental cause for early death by 2050. Nearly 3.6 million people are expected to die every year due to respiratory diseases caused by breathing in air pollutants. The report has earmarked China and India as danger zones vis-a-vis urban air pollution deaths.

A CNG Bus in New Delhi

One of the ways in which urban air pollution can be reduced is by using CNG to fuel public transport bus fleets. CNG is a clean alternative to petrol and diesel, with fewer dangerous emissions of gas and particulate matter. In addition, conversion of buses to CNG normally has a big impact on pollution as buses travel more kilometres in the city and contribute more to the pollution load. The conversion therefore results in greater gains.
CNG also requires a specific infrastructure. Public transport buses travel a specific route with a fixed distance every day. They will also visit a central depot on a daily basis thus making it easy to calculate the amount of CNG that has to be provided and where CNG refuelling facilities have to be set up.
CNG Buses Vs Diesel Buses: Studies have revealed that CNG buses reduce Carbon dioxide emission by 20 to 30 percent as compared to diesel buses. The biggest difference is in relation to particulate matter (PM) emissions. The use of CNG buses can reduce suspension of particulate matter in the atmosphere by as much as 60 to 97 percent and carbon monoxide emissions by 52 to 84 percent.
With CNG bus fleets for public transport, cities can offer their citizens cleaner and fresher air to breathe in, bringing about a vast improvement in the quality of life. CNG buses make up part of the urban public transport system in countries like China, US, Europe, Canada and India.
The Success of CNG Bus Fleets in Reducing Air Pollution: Two Indian cities – Delhi and Ahmedabad have seen remarkable improvement in air pollution levels since the introduction of CNG buses in their public transport systems. Prior to the introduction of CNG fuelled public transport, Delhi was regarded as one of the most polluted cities in India and the world. The haze of pollutants in the air created smog and was a health hazard for the city’s population. But a study conducted by the Washington DC think-tank, Resources for the Future showed that the air quality in Delhi improved significantly, post the entry of CNG buses.
The study concluded that of all the different interventions taken by the government to reduce pollution level in the city, the maximum positive impact was registered by the introduction of the CNG fleet. It brought about significant reduction in the amount of particulate matter, carbon monoxide and sulphur di-oxide in the Delhi air. The city which had the dubious distinction of being one of the most polluted cities in the world in 1999, bagged the Clean City International Award in 2003.
Ahmedabad too has seen great improvements in the air quality since the introduction of CNG bus fleets within the public transport system. In 2001, Ahmedabad was found to be the fourth most polluted city in India. With the introduction of CNG, the city’s ranking improved to 13th in 2005 and 66 in 2009. By 2011, the city had a total of 107024 CNG vehicles, which included buses and three-wheelers.
CNG can thus make a huge difference to city living. In developing countries like India, rickety and poorly maintained public transport systems are often responsible for increasing air pollution levels. Conversion to CNG provides a greener, economical alternative.