- The interest and attention on cleaner energy sources like CNG and LPG have increased
- Though both are gases and cleaner alternatives to fossil fuels, they possess major differences
- From storage to composition, TheRadar highlights eight major differences between CNG and LPG
There has been an increased call for a move to cleaner fuels given the environmental impact of fossil fuels like gasoline, petrol, diesel and coal.
Cleaner energy sources such as Liquefied Petroleum Gas (LPG), Compressed Natural Gas (CNG) and Liquefied Natural Gas (LNG) have become topical with the government and environmental activists advocating their adoption.
This necessitated the launch of the Presidential Initiative on Compressed Natural Gas (Pi-CNG). Since then, attention has been on the conversion of vehicles from petrol-powered to CNG-powered given its cost-effectiveness.
The Federal Government also established conversion centres across the country for effective conversion and safety.
However, with the recent explosion of a vehicle converted to CNG in Benin, Edo State, it is important to note the key differences between CNG and Liquefied Petroleum Gas (LPG), commonly known as cooking gas.
8 key differences between CNG and LPG
1. Storage
CNG is stored under high pressure while LPG is stored under moderate pressure. LPG uses lighter, less thick cylinders than CNG because of its lower pressure and less complicated storage needs; CNG’s high-pressure demands far more durable materials.
LPG can be stored in pressurised tanks at a lower pressure of around five to 10 bars, and at ambient temperature, in contrast to CNG.
2. State
While CNG is a gas, LPG is a liquid. CNG is the gaseous product of petroleum and the first product separated during the distillation process. CNG is odourless, tasteless and non-toxic.
LPG is a liquefied gas and a byproduct derived from extracting crude petroleum. LPG weighs twice as much as air and is a colourless, odourless and highly flammable explosive gas.
3. Composition
CNG is composed of 93.05 per cent methane, nitrogen, carbon dioxide, propane and traces of ethane. During the combustion process, CNG emits a lower percentage of greenhouse gases when compared to other fuels. Its environmental friendliness makes it a cleaner fuel alternative.
Methane is a cleaner-burning fuel, releasing fewer emissions than other fossil fuels, making it a preferred alternative in vehicles aiming to reduce carbon.
On the other hand, LPG is a mixture of propane and butane with traces of propylene and butylenes, leftovers from the processing of natural gas, the refining of oil, and natural gas extraction.
4. Emissions
CNG produces fewer pollutants and other harmful emissions, including CO2, carbon monoxide, nitrogen oxide and particulate matter, making it an eco-friendly option for powering vehicles.
LPG is commonly used for heating and cooking and as an alternative fuel for vehicles. It is cost-effective and has a lower environmental impact than fossil fuels like gasoline and diesel.
5. Cost
CNG is cheaper than LPG. In Nigeria, a standard cubic meter of CNG currently goes for N200 while the average price of LPG is N1,500/kg.
The cost-effectiveness of CNG is also why the federal government is advocating its adoption as a vehicle power source instead of petrol.
Recall that the cost of petrol has been on the increase since May 29, 2023, when President Bola Tinubu announced the removal of fuel subsidy. The price of fuel increased from an average of N238.11 in May 2023 to over N1,000 in October 2024. The NNPCL recently announced the latest hike in fuel price, the second time in two months, with prices now approximately N998 in Lagos from N885 and N1,030 in Abuja from N897. The price has also been adjusted to N1,025 in Lagos and N1,060 in Abuja.
6. Safety
CNG is lighter than air, which makes it easily dissipate (evaporate) if a leak occurs. LPG, however, is flammable and can be dangerous in the event of a leak.
7. Availability and usage
LPG is relatively easier to transport and store than CNG, which is why the product is widely available. Its high energy level makes it effective, and its cylinders are common in many Nigerian households. CNG, on the other hand, is only beginning to gain popularity in Nigeria.
CNG is typically used as a substitute for gasoline in automobiles, while LPG is often used in the industrial, refrigeration, agricultural and catering industries.
8. Energy content
CNG has a lower energy density than LPG. This means that to produce the same amount of energy as LPG, more CNG is needed, and cars will need bigger storage tanks or more frequent refuelling.
LPG is more energy-efficient per unit volume than CNG because it has a higher energy density. Because of its ability to produce greater energy from a lesser quantity of fuel, LPG is commonly used as an alternative fuel in some types of cars and for cooking and heating.
Timeline of cooking gas price hike in 2024
The average price of refilling 5kg and 12.5kg of cooking gas fluctuated between January and September 2024, reaching N6,699.63 and N16,313.43, respectively.
Using data gathered from the National Bureau of Statistics (NBS), TheRadar highlights the timeline of changes in the price of the product in the nine-month period.
