Advantages and Disadvantages of CNG

A mixture of hydrocarbons containing about 80% to 90% methane as CNG gas has a low energy density because it is compressed at a pressure of 200 to 250 kg/cm². This enables vehicles to store the gas in a cylinder and is thus called Compressed Natural Gas. Better than petrol, it operates at one-third the cost of conventional fuel and hence has become increasingly popular among vehicle owners.

Because it is lead-free and has the potential to lower harmful emissions while also extending the lifespan of spark plugs, it is frequently referred to as a "green fuel." It has been noted that using CNG as a fuel extends the life of lubricating oil in nations where this fuel is used because it keeps crankcase oil clean by diluting it. Alternative fuels like Liquefied Petroleum Gas (LPG) and Compressed Natural Gas (CNG) will be used in cars more and more in the coming millennium. In Mumbai, more than 10,500 private vehicles and taxis, as well as Delhi's entire public transportation system, run on CNG.

Automobile manufacturers are testing both dedicated and bi-fuel LPG/CNG and CNG engines in their vehicles. Although these two fuels can only be used in specific applications, such as commercial and public transportation vehicles, they can never totally replace gasoline and diesel. Diesel has traditionally been regarded as being more environmental friendly than gasoline because it uses less fuel and provides 15 to 20% more miles per gallon. Diesel, however, is now widely acknowledged to be exceedingly bad for both the environment and human health in the 1990s.

An ultrafine of one millimeter or smaller is hazardous to health, according to experiments. The authorities have emphasized the usage of alternative fuels like CNG and LPG, which are less dangerous and more affordable, in light of how critical the situation is.

Making of CNG

Natural gas is generated from ancient plants, animals, and microorganisms, just as other fossil fuels like coal and oil. There are numerous hypotheses that attempt to explain how fossil fuels came to be. The prevailing idea holds that they developed underground in harsh environments. Layers of soil, sediment, and occasionally rock cover decomposing plants, animals, and microorganisms throughout time. Over millions of years, organic stuff becomes compressed. The temperature increases when organic matter sinks further into the Earth's crust.

The carbon bonds in organic materials are broken when compression and high temperature are combined. The natural gas thermogenic methane is produced by this molecular dissociation. Methane (CH4) is made up of carbon and hydrogen and may be the most prevalent organic substance on Earth. Depots for natural gas are frequently found alongside depots for oil. Natural gas reserves found nearby the Earth's surface are typically dwarfed by neighbouring oil reserves. More natural gas than oil is found in deeper deposits that originate at higher pressures and temperatures. Pure natural gas may be found in the deepest reserves.

However, it's not necessary to produce natural gas underground. Methanogens, which are little microbes, can also create it. Methanogens are found in low-oxygen areas close to the Earth's surface as well as in the intestines of animals, including humans. For instance, decomposing materials found in landfills are broken down by methanogens, producing a kind of methane called biogenic methane. Methanogenesis is the process by which methanogens produce methane, a component of natural gas.

While new technologies are being developed to trap and harvest this potential energy source, the majority of biogenic methane still escapes into the atmosphere. A natural gas called thermogenic methane, which develops deep beneath the surface of the Earth, can also be released into the atmosphere. Some gases have the ability to rise through porous rock or other permeable material and finally diffuse into the atmosphere. The majority of thermogenic methane, nevertheless, finds geological strata that are too impermeable for it to escape when it rises to the surface. Sedimentary basins are the name given to these geological formations.

Large natural gas deposits are trapped in sedimentary basins. A hole (also known as a well) must be dug through the rock to allow the gas to escape and corrode in order to access these natural gas sources. Natural gas-rich sedimentary basins can be found all over the world. Natural gas can be found in the dry deserts of Saudi Arabia, the wet tropics of Venezuela, and the chilly Arctic of the US state of Alaska. Outside of Alaska, the basins in the United States are mostly located around states that border the Gulf of Mexico, like Texas and Louisiana. North Dakota, South Dakota, and Montana, three northern states, have lately built sizable drilling operations in sedimentary basins.

Uses of CNG

Cooking: Natural gas can be used directly for cooking. In comparison to an electric oven, it frequently offers superior temperature control and consumes much less energy. But even if we don't utilise gas directly, we almost certainly do so indirectly (via electricity generation).

Heating of water: Yes, we use it to heat the water as well as our rooms. Compared to electricity, natural gas is cheaper and heats more quickly.

Air conditioning: Air conditioning is the best cooling technique. We use natural gas either directly or indirectly in practically every situation. The majority of the time, we use natural gas indirectly (because we use electricity); however, there are models and products that use natural gas directly. Households do not favour these.

Uses of CNG in Industries

• Natural gas is used by manufacturers to create things like heat and light.
• The manufacture of products such as paper, glass, brick, steel and iron require a lot of different types of fuel.
• Raw input materials, such as hydrogen, are used to produce substances that can be used to make things like clean energy.
• These essential building blocks are also very important for the production of fertilizers and many other petrochemical products.
• Medical products, such as intravenous lines and bags, gloves, masks, and catheters, are made of different materials, depending on where these products are made and the treatments that are used in these products.
• One component of these products is acrylic lenses. These lenses are made of various materials, such as glass and plastic, and are used to improve vision in people with glaucoma.
• CHP is a process that captures excess heat and steam generated during the manufacturing process and feeds it back into the system. This reduces emissions and costs, making CHP a highly efficient process.

Difference between CNG and LPG

• CNG is mostly utilized as auto fuel. While LPG can be used as both motor fuel and for cooking.
• Natural gas is compressed to create CNG. LPG is created from a combination of several gases.
• On the one hand, LPG is a combination of butane and propane gases. The compressed form of natural gas is known as CNG.
• LPG exists in two states: a liquid at high temperatures and a gas at room temperature. To liquefy, CNG needs a temperature below 0°C.

Difference between CNG and PNG

• Compressed natural gas is what CNG is officially known as whereas PNG is known as piped natural gas.
• Natural gases include both CNG and PNG. While PNG only needs a pressure of 4 bar to 21 millibars, CNG needs the correct pressure (up to 200 bar) to operate.
• PNG is utilized for household and industrial purposes, whereas CNG is used as automobile fuel.
• While PNG is utilized through pipes, CNG is stored in cylinders.
• In PNG and CNG, pollution is merely little.
• CNG must be refilled at a CNG pump when it runs out, but PNG is accessible through pipes around-the-clock.

Advantages of CNG

• Vehicles driven by CNG are 40-50% more inexpensive than those powered by LPG and 70-80% more efficient than those powered by gasoline.
• Because it is changed every 35-40 thousand kilometers when utilizing CNG, the engine is not harmed.
• Compared to engines powered by other forms of fuel, CNG engines are stronger and last longer.
• There is no chance of natural gas being stolen outside because it is kept apart from other liquid fuels. The risk of theft is eliminated.
• Natural gas does not contaminate the environment like other fuels like gasoline, LPG, and diesel that are delivered by trucks because it is transported through pipelines.
• Gasoline has an ignition point of 300 °C, LPG of 400 °C, and compressed natural gas of 650 °C. CNG is the most challenging fuel to ignite in terms of its physical characteristics.
• Natural gas is less likely to ignite or explode than other fuels because, unlike LPG, gasoline, etc., it vaporizes fast into the air in the event of an accident or issue. This is because natural gas is lighter than air.
• CNG has lower maintenance costs.
• Natural gas is recognized to create 25% less carbon monoxide and 90% less nitrogen when compared to other fuels. Unlike other fuels, natural gas doesn't contain aldehydes or other gaseous poisons.
• The percentage of noise generation is 30% lower when compared to engines using other fuel types.

Disadvantages of CNG

• More room is needed for the cylinders in CNG vehicles. The cylinder is typically positioned in the trunk or boot area of CNG vehicles, which reduces the boot capacity. Less luggage enters the car as a result.
• Every big or small city or hamlet town has a petrol-diesel fuel station. However, the country still has a severe lack of CNG stations. In such a scenario, it is vital to fill up the CNG tank before leaving the city or embarking on a lengthy drive.
• CNG car owners claim that the vehicle does not perform as expected. This explains why CNG vehicles are less advanced than gasoline-powered vehicles.
• You must be more cautious about your car's maintenance routine if you are moving to CNG. This is due to CNG engines' fuel and spark plugs wearing out more quickly than petrol-powered ones do. You should be more careful with the engine if your CNG vehicle runs more frequently.
• Negligence in maintenance might seriously harm the engine. You must monitor how your car is performing. Driving a CNG vehicle necessitates greater attention to detail.