Compressed natural gas (CNG) is a natural gas under pressure that remains clear, odourless and non-corrosive. Although vehicles can use natural gas as either a liquid or a gas, most vehicles use the gaseous form, compressed to about 218 kg/cm2.
CNG can be used as an alternative to conventional petrol and diesel fuels.
While we await the implementation of the conversion of petrol-powered cars to CNG and LNG powered cars, how does the implementation benefit the Nigerian public?
In December 2020, the Federal Government rolled out its National Gas Expansion Program (NGEP), which involves the conversion of fuel-powered cars and generators from petrol to gas. The program which is expected to deliver at least one million vehicle conversions by the end of 2021 aligns with the Federal Government’s plan to make gas the first-choice source for cheaper and cleaner energy.
In addition, Mohammed Ibrahim, head of the government committee in charge of the NGEP, said “The need to switch from petrol to gas was necessitated by the deregulation of petrol by the government, which has led to increment in the domestic pump prices in recent times,”.
In his speech during the lunch of NGEP, the NNPC head Mele Kyari said “to support this effort(NGEP), NNPC is providing free conversion services in some selected NNPC Retail Filling Stations to assist interested motorists (to) switch from PMS to Autogas especially in areas with existing Autogas service stations in the Federal Capital Territory, Abuja, Kaduna, Kano, Kogi, Kwara, Ogun, Ondo, Oyo, Lagos, Edo, Delta, Rivers and Bayelsa States.”
Similarly, the president at the 2021 Africa Regional Heads of Government Commonwealth Roundtable chaired by the Prince of Wales, Prince Charles, reminded the world of Nigeria’s plan to replace petrol with CNG. While reiterating Nigeria’s commitment to a just transmission to net zero-emission, President Buhari who was represented by the Vice President, Osibanjo, said “We also have our Natural Gas Expansion Programme. This is where we are using Compressed Natural Gas (CNG) and Liquefied Petroleum Gas (LPG) in order to replace the use of Premium Motor Spirit (Petrol), and this is going on now, we are actually trying to fit and retrofit existing petrol stations so that the use of cleaner fossil fuels will replace it.”
Benefits of implementing CNG as an alternative fuel for automobiles: What data says
According to a report on “CNG vs traditional gas fueling” released by Virginia natural gas, “the fuel economy of a gasoline (petrol) vehicle converted to run on CNG is about the same, so you can compare fuel costs on an “apples to apples”. As such, with a report revealing that an average of 10 litres of petrol is consumed in 100km, it means 10 litres of CNG is also consumed in 100km.
However, based on current price differentials in Nigeria, a Dataphyte analysis revealed that if CNG is adopted as automobile fuel, there is the potential for a car driver to save six hundred and eighty nairas (N680), driving a CNG powered car over driving a petrol-powered car for each 100km travelled. This amount was arrived at assuming that the CNG and petrol-powered cars are of a similar model and are both driven for 100km.
Potential Savings Using CNG
| Fuel type | Fuel consumption per 100km | Price of fuels (Naira) | Total fuel cost per 100km (Naira) | Savings on CNG over petrol (Naira) C= A-B |
| Petrol | 10 litres | 165 | 1650 (A) | 680 |
| CNG | 10 litres | 97 | 970 (B) |
The price of petrol used for the potential savings using CNG analysis was obtained from the current pump price of petrol as at the time of this report. On the other hand, the price of CNG used was a Federal Government estimate gleaned from a recent report. Based on the revelation of the potential cost savings in using CNG, it is expected that transportation would be cheaper and people would find it easier to move around.
Reduction in Air and Noise Pollution
A report by Haeng & Mahmud on “Benefit analysis of CNG as an automobile fuel” revealed that there is a significant reduction in the emission of CO2 by 70% when CNG is used as transportation fuel compared to when PMS(petrol) or diesel is used.
Similarly, a report on the “Technical overview of compressed natural gas (CNG) as a transportation fuel” revealed that CNG automobiles make less noise than gasoline and diesel automobiles.
Goyal and Sidhartha, also reported that both New Delhi in India and Brazil have shown a drastic reduction in air pollution from the time they adopted the use of CNG automobiles.
According to IEA data on CO2 emission by sector in Nigeria, there is a steady rise in CO2 emissions in Nigeria due to the transport sector. A review of the data shows that in 2018 the transport sector accounted for the largest sources of emission with 67 million tonnes of CO2, of which road transport accounted for 66.5 million tonnes.
Source: IEA
The number of petrol and diesel vehicles in Nigeria over the years quite justifies the CO2 emissions from the transport sector. As a report notes that Nigeria only had 6,000 CNG automobiles in 2016 in comparison with the 11.7 million total registered vehicles in 2018.
CNG will provide energy security
A report by Dioha and Kumar on sustainable pathways for land transport in Nigeria suggest that “alternative transportation fuel of low carbon emission (CNG) would increase energy security. They asserted that “this is very likely as there would not be much dependence on conventional gasoline (petrol) and diesel in Nigeria. Especially since oil prices are very volatile and there is also an occasional scarcity of oil supply.”
In Nigeria, the unpredictability of the petrol market often leads to scarcity of petrol. During these times, petrol is usually sold at a very high price and this directly increases the cost of transport, and of every other thing indirectly. This makes it more difficult for Nigerians to cope.
CNG will ensure increased car efficiency
Ogunlowo, Bristow, and Sohail, in their article on “Developing compressed natural gas as an automotive fuel in Nigeria: Lessons from international markets,” notes that because CNG is a cleaner fuel than petrol, a CNG car will require lower routine maintenance. And this will lead to a CNG car having an additional service year of
2 – 3 years in comparison to conventional fuel (petrol) automobiles.”
Ubani and Ikpaisong, in an article “Use of CNG as auto fuel in Nigeria,” notes that CNG automobiles have more efficient engines, longer-lasting spark plugs, and reduced
routine oil change. Also, the brake thermal efficiency of CNG is between 5 – 12% higher than that of gasoline (petrol) Automobiles, said Khan, Yasmin, and Shakoor, in a report on “Technical overview of compressed natural gas (CNG) as a transportation fuel.
CNG powered cars are Safer
Khan, Yasmin and Shakoor further note that CNG being a gas means it just disappears into the air when there is a leakage instead of leading to a pool of fuel like gasoline(petrol), therefore reducing its probability to cause a fire outbreak when there is a leakage.
In a similar sentiment, Ogunlowo, Bristow, and Sohail suggest that the reason for the reduced probability of CNG to cause fire is because CNG is less combustible than gasoline and can only ignite between 5% to 15% concentration in air.
How do we ensure an efficient implementation of CNG as an automobile fuel in Nigeria?
Already, a review of the foreign trade statistics of the NBS in 2020 reveals that used vehicles, with diesel or semi-diesel engine, of cylinder capacity >2500cc, was amongst the top five imported products in 2020. Hence, more needs to be done as regards the use of CNG as an alternative fuel to gasoline and diesel.
Dioha and Kumar, suggests the development of a carbon tax system to mitigate CO2 emissions by about 26.9% by 2050 in Nigeria. They argued that Carbon tax policies would increase the cost of gasoline and diesel while lowering the cost of alternative fuel like CNG. And this would force Nigerians to purchase vehicles that run on CNG, as they would be more economically viable.
Also, since the majority of Nigerians do not have sufficient information about compressed natural gas (CNG) vehicles, the government would do well to raise public awareness about the environmental and economic advantages of using CNG over petrol.
This story was produced under the NAREP Media Oil and Gas 2021 fellowship of the Premium Times Centre for Investigative Journalism