Compressed Natural Gas: All you need to know about Nigeria’s alternate energy - Dubawa (2024)

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Compressed Natural Gas (CNG), otherwise known as CNG, is not new to the Nigerian energy ecosystem, but it will be the next subject to be accommodated by Nigerian energy consumers.

Besides its great benefits, this energy source will help reduce Greenhouse Gas emissions and be the solution that most Nigerians are craving at this hard time of petrol subsidy removal. We also can not shy away from the fact that the conversation around this subject has met a lot of mixed reactions, especially because of the safety concerns, urgency and cost implications.

This article is to bring readers up to speed with all there is to know about CNG, especially in the Nigerian context.

What is CNG?

CNG is natural gas in a compressed form. It becomes lighter than air after the compression, usually about one per cent of its original volume. CNG is safe and clean, given its non-toxic and non-corrosive nature. It is also tasteless, colourless and odourless.

Composition, transportation and storage of CNG?

CNG comprises mainly hydrocarbon gasses and vapour and contains predominantly methane. It is a by-product of coal mining or comes from crude oil production.

After extraction, it is stored in thick-walled high-pressure tanks, and this pressure is usually around 200 to 250 bar. CNG is often transported in these thick-walled tanks or pipelines.

For further information on the storage and transportation of CNG, read here.

Uses and Benefits of CNG

CNG is mostly used to generate energy (heating or fuelling). Compressed Natural Gas is an effective and efficient way of fuelling. Here is how the METGroup Countries described the efficiency of CNG in its December 2021 energy insight publication.

The benefits of this source of energy are both pocket and climate-friendly. Although the burning concern in Nigeria is more of a pocket-friendly benefit based on the current cost of petrol, climate-friendly concerns have been here for decades.

Unlike petrol and diesel, CNG releases a smaller amount of greenhouse gas (GHG). Hence it is described as cleaner energy compared to the former. There is a 70% reduction in GHG emissions when CNG is used against petrol or diesel.

Several other benefits include safe fuel, high auto-ignition temperature, low operation cost, dual facility and increased life of oils. You can read about all of these here, and there are also more insights into the benefits here and here

Safety of CNG

CNG is safer to use as it reduces GHG emissions by 70%. It is safer than other types of fossil fuel in terms of spillage because it is lighter than air. This makes it disperse quickly when released. It has a higher ignition temperature which means it does not ignite easily. The storage systems used for compressed natural gas are infinitely stronger than the gasoline tanks on cars and trucks today. Here is a detail for further reading.

Despite being a safer energy source, here are some precautions to follow while using this energy, especially as it is usually compressed under very high pressure.

Where Nigeria stands on CNG today

Nigeria’s natural gas deposit as of 2022 is about 208.62 trillion cubic feet, and as stated above, This energy source is not necessarily new to Nigeria. The idea was first introduced in 1997, and the conversation has continued ever since, as shown here, here, here and here.

It will interest you that Nigerian Independent Marketing Company (NIPCO) Plc launched the country’s first compressed natural gas (CNG) in Benin City for vehicular and sundry applications in January 2010. Governor Godwin Obaseki of Edo state said in June 2023 that about 5000 vehicles run on CNG in the state.

Also, the Group CEO of the Nigerian National Petroleum Company Limited (NNPCL), Mele Kyari, confirmed during an energy summit in April 2023 that Nigeria has the infrastructure to transport about 6.9 Billion Standard Cubic Feet (BCF) of gas to support power generation and gas-based industries.

In this publication, a gas company known as Powergas said it operates five Compressed Natural Gas (CNG) plants across Nigeria.

This report also showed a detail on domestic gas utilisation in Nigeria, and recently, the conversation around using CNG as an alternative to petrol or diesel gained momentum. Similar reports were also cited here and here.

Expert opinion

The President of the National Industrial Safety Council of Nigeria, Festus Daniel, said that using CNG is as safe as cooking with gas at home, so long as all safety precautions are followed. Regarding how safe it is to convert a petrol-powered generator to a CNG powered, Mr Daniel said it is safe but advised that the safety is only guaranteed if the petrol/diesel generator or vehicle to CNG is given to experts. He made this known during an interview with Nigeria Info FM, Lagos.

The conversion mechanism of petrol engine to CNG engine

In this report called “How do Natural gas vehicles work,” the Department of Energy explained the CNG engine mechanism: “Natural gas is stored in a fuel tank, or cylinder, usually at the back of the vehicle. The CNG fuel system transfers high-pressure gas from the fuel tank through the fuel lines, where a pressure regulator reduces the pressure to a level compatible with the engine fuel injection system.”

Some of the spare parts that will be needed to convert a petrol engine to a CNG engine in a vehicle are air/gas mixer, pressure regulator, high-pressure line, CNG filling valve, CNG tank, manometer, selector switch (to switch between petrol and CNG), emulator and heating system.

For more details on how this works, check here and here.

Conclusion

The idea of harnessing CNG has been in Nigeria’s policy pipeline for decades. We have also established that its utilisation has been put to a certain level of practice. With the petrol subsidy gone, there is no better time to take full advantage of this efficient and climate-friendly energy source.