Compressed Natural Gas (CNG) is a substitute for gasoline (petrol) or diesel fuel. It is considered to be an environmentally “clean” alternative to those fuels. It is made by compressing methane (CH4) extracted from natural gas. Argentina and Brazil are the two countries with the largest fleets of CNG vehicles. As of 2005, Pakistan is the largest user of CNG in Asia, and third largest in the world.
The Compressed Natural Gas (CNG) sector of Pakistan by end of 2007 has attracted over Rs 70 billion investments during the last few years as a result of liberal and encouraging policies of the government. Presently, more than 2,700 CNG stations are operating in the country in 85 cities and towns, and 1000 more would be setup in the next three years. It has provided employment to above 30,000 people in Pakistan.
Over 2 million vehicles were converted to CNG as of march 2009, showing an increase of 35 percent yearly. On average 29,167 vehicles are being converted to CNG every month. All Pakistan CNG Association (APA) Sana-ur-Rehman confirms that CNG stakeholders have invested Rs.90 billion in this sector and another Rs 20 billion investment is in pipeline. The CNG consumers had invested around Rs 60 billion in converting their vehicles to CNG.
The CNG was replacing at least 6.12 billion liters of petrol every year and saving foreign exchange to the tune of billions of dollars. The CNG sector pays 24 percent sales tax and 4 percent withholding tax to the government.
Moreover, the CNG is contributing tremendously towards maintaining the air pollution level lower since it emits almost 85 percent less harmful gasses, zero lead and zero particulate matter.
Compressed Natural Gas (CNG)
Compressed Natural Gas (CNG) is a substitute for gasoline (petrol) or diesel fuel. It is considered to be an CNG has grown into one of the major fuel sources used in car engines in Pakistan, Bangladesh and India. The government of Punjab, Pakistan, the most populous province of that country, has mandated that all public-transport vehicles will use CNG by 2007.
CNG conversion 3rd generation
environmentally “clean” alternative to those fuels. It is made by compressing methane (CH4) extracted from natural gas. It is stored and distributed in hard containers, usually cylinders.
Conversion has been facilitated by a substantial price differential with liquid fuels, locally-produced conversion equipment and a growing CNG-delivery infrastructure. A ‘Blue-network’ of CNG stations is being developed on the major highways of the Southern Cone (including Chile and Bolivia) to allow for long-haul transportation fuelled by CNG.
According to the International Association for Natural Gas Vehicles, Pakistan has the third-largest number of natural gas vehicles. In the Middle East and Africa, Egypt is a top ten country in the world with more than 63000 CNG vehicles and 95 fueling stations nationwide. Egypt was also the first nation in Africa and the Middle East to open a public CNG fuelling station in January 1996. Brisbane Transport and Trans-Perth in Australia have both adopted a policy of only purchasing CNG buses in future; the former purchasing 216 Scania L94UB and 180 MAN 18.310 models, with the latter purchasing 451 Mercedes-Benz OC500LE buses, including 58 articulated buses. Brisbane Transport has also ordered up to 30 articulated CNG buses on MAN chassis’.
During the 1970s and 1980s, CNG was commonly used in New Zealand in the wake of the oil crises, but fell into decline after petrol prices receded.
CNG can easily be used in Otto-cycle (gasoline) and modified Diesel cycle engines. Lean-burn Otto-cycle engines can achieve higher thermal efficiencies when compared with stoichiometric Otto-cycle engines at the expense of higher NOx and hydrocarbon emissions. Electronically-controlled stoichio-metric engines...