CNG: Advantages And Disadvantages

Compressed Natural Gas (CNG) is a fuel that needs no introduction. It is a cheap fuel to make and use, which is why it is so widespread in public transport. Not to mention the fact that the second hand car market is greatly supported by CNG kits. Vehicles like the Honda Civic, Accord and Toyota Corolla are favorites to be bought second hand for the same price as a hatch-back and then have green fuel kits used to make them easy on the pocket. With diesel deregulation soon to kick in, the prices of the oil will head north soon, so CNG seems like a good investment for those with regular usage. Here’s a brief look at the advantages and disadvantages of CNG:

Advantages:

• The most obvious advantage of them all is the cost. Rickshaws, taxis and buses use CNG as it is a very cheap fuel and facilitates high running with lower costs. On an average CNG costs around half or 1/3rd the amount regular fuel. In fact, in a brief survey, a hatch-back like the Hyundai i10 running on CNG and an entry level sports bike like the Honda CBR250R have similar fuel costs for an average running of around 50 kms a day.

• It is a greener fuel. The emissions and hydrocarbons that are released as a by product of CNG usage are lesser than those created by regular fuel. Carbon monoxide emissions are down by 70-85% while hydrocarbon levels are reduced by 40-60%.

• The price fluctuation of natural gas is less. Look back over the past few years and you’ll notice that petrol and diesel prices have been on a roller coaster ride, but CNG has a relatively linear movement. This is mainly because of domestic production which has no dependency on international movements.

• Engine life improves. Contrary to popular belief, CNG is actually a better fuel for improving engine life as the carbon levels are greatly reduced.

Disadvantages:

• The performance of the car is reduced significantly. On an average CNG users experience a crash of about 10% in performance. Acceleration is slower so you may have to rev the engine more to get going. Essentially this is the reason why people believe CNG reduces engine life. The issue is, drivers expect petrol like performance from CNG and rev more to get it. This eventually results in more wear and tear.

• The storage space is eaten up badly. CNG tanks are easily the size of a large bag, so boot space is reduced or removed entirely as the fuel storage tank takes up all the room.

• Availability is not as widespread as regular gas stations. Within the city users probably have a list of stations that fall in their route, but beyond that it is an uncertainty. This is the reason why cars aren’t made to run exclusively on CNG.

• Blocked injectors. Cars with CNG kits should always be started on petrol and run for a few kilometers before being switched to the green fuel. This warms up the engine better and gets the motor well lubricated. Petrol is expensive so drivers often chose not to use it. This causes the injectors to crust and get blocked. Not to mention the fuel laying in the tank ages and unlike wine, does not get any better.

• Fuel range. Although CNG is a cheaper fuel, the actual range on just CNG is lesser than petrol. Not to mention, running on a close to empty tank reduces the pressure and increases the risk of the valves bursting. So, even if the car does use CNG, it is always wise to keep a regular flow of petrol both in the tank and in the engine usage.

• It is important to note that CNG kits cost around Rs 30,000 to install. So, if you do plan on having a kit put in, be sure that you actually need it and have a high average running.