We are seeing more and more vehicles running on natural gas. For example, many buses in the Netherlands already run on fuel. And in other countries, CNG is also increasingly used. Good examples are China, Brazil, Argentina, the United States and India. But the supply of cars running on natural gas is also increasing in the Netherlands. What do you need to know about this fuel? What are the differences, what does it cost, is it environmentally friendly and what does the future look like?
Natural gas or CNG?
Natural gas is the name for the gas that is extracted from the ground. This is the same gas that we receive in our homes for heating our boilers and for cooking. CNG stands for Compressed Natural Gas, or compressed natural gas. CNG is ordinary natural gas that is made smaller at a pressure of 200 bar. Another name that is used is ‘gas under pressure’.
Natural gas as a vehicle fuel
Nowadays natural gas can also be used as fuel in our vehicles. In addition to petrol, diesel and LPG, it can also run on natural gas. At the moment, this offers two major advantages: namely for the environment and your wallet. When you drive on gas, less NOx, CO2 and particulate matter is emitted compared to other fuels.
Because driving on natural gas is better for the environment, it is encouraged by the government. As a result, you pay less tax on natural gas as a fuel than on diesel or petrol. So you pay less at the pump. With petrol you pay 68 cents and with diesel 35 cents per liter in excise duty. Natural gas is not subject to excise duties, but energy tax. And if that is as fuel in your car, it is only 3 cents per cubic meter.
What is different about cars on CNG?
The engine technology is not fundamentally different when you drive on natural gas. This is also evident from the fact that you can always switch to petrol. The differences are mainly in the fuel system. Both in terms of storage and supply to the engine. The gas is transported to the engine, whereby the pressure is reduced from 200 bar to 6 bar.
In addition, more volume is needed for the storage of natural gas, so you need more space for gas tanks. These are cleverly concealed by the car manufacturers in the car, so that you have as little trouble as possible. After all, you don’t want to sacrifice your entire luggage space for fuel storage.
Natural gas units: liters, kilograms or cubic meters?
We are used to calculating in liters with diesel, petrol and LPG. That compares easily, but is not always convenient. For example, the consumption of a diesel and petrol car is not the same, so that the basic fuel prices do not fully apply. If you look at LPG, it becomes even more difficult. A liter of LPG in the winter contains less energy than in the summer. This is due to the difference in temperature.
At our home, gas is billed in cubic meters or cubic meters. As with LPG in liters, the amount of usable energy in a cubic meter of gas depends on the temperature. For that reason, CNG is calculated in kilograms. The amount of energy per kilogram is always the same. One kilogram of natural gas corresponds approximately to 1.25 m3 (cubic meter).
What is the consumption and range like with natural gas?
The consumption of CNG is of course not the same for every car model. As with other fuels, this strongly depends on engine performance, weight of the car and handling. For passenger cars you can assume that you can travel about 10 to 20 kilometers on one kilogram of CNG. So on average about 15 km. But if you look at an MPV or a van, this will quickly decrease. But that is of course also the case with petrol or diesel.
The range is determined by the consumption in combination with the tank content. With a passenger car you should think of a tank capacity of about 15 to 25 kilograms. For example, the Seat Leon 1.4 TGI has a tank capacity of 14 kg, an Opel Zafira 1.6 has a tank capacity of 25 kg and a Mercedes B200 has a capacity of 21 kg. If you assume 20 kg content and a consumption of 1:15, you get a range of 300 kilometers. That is not very much and at the same time a disadvantage of CNG. Especially compared to diesel.
Refueling with natural gas: how and where?
Refueling LPG is not very complicated. Basically no more difficult than with other fuels. As with LPG, you really have to hook the shot to the tank as it has to remain a closed system under pressure. An additional advantage over classic liquid fuels is that gas refueling is clean and odorless.
The availability of petrol stations where you can buy natural gas is constantly improving. But in April 2015 that is still much more limited than the other fuels. If you want to go for a car on natural gas, then this is something to specifically check. Availability is still very limited in certain areas in the Netherlands. If you happen to live there, you don’t want to have to make a detour every time just to refill your tank.
Refuel at home or at work?
There are also possibilities to make a refueling option at work or even at home. This is possible because CNG is just the same natural gas that our central heating boilers use. However, you do need a special device for this, a so-called home filler. This is necessary because the gas in your car must be pressurized to 200 bar. The gas in our gas pipes has not been brought under such a high pressure.
Filling your car tank in this way, however, takes a relatively long time. You will therefore have to connect your car to the home filler for hours. This can be done at night, for example. The result is that you cannot simply fill multiple cars in this way. This depends on the capacity of the home filler you are taking. The cheapest home fillers cost around 3,000 euros.
Can you refuel with natural gas abroad?
If you are going abroad with your car, it is wise to first check the availability of natural gas on your route and destination. This is very different per country. In Germany, for example, it is also increasingly common. But some other countries are still further behind. So always look for recent information. Of course you can always rely on petrol, but ideally you only do that in exceptional cases.
Incidentally, you do not need a gradient for refueling natural gas, as is sometimes the case with LPG.
Is driving on natural gas dangerous?
Driving on natural gas is not dangerous. It is even safer than driving on LPG. This is because LPG is heavier than air. For this reason, cars on LPG are also refused in underground parking garages. This does not apply to CNG. Should that escape, the gas will rise into the air and disappear. Not that the chance is very high, because the technology has long proven itself and all installations meet safety requirements.
Is natural gas as a fuel environmentally friendly?
Natural gas, like petrol, diesel and LPG, is a fossil fuel that is combusted in the engine block. This involves the necessary emission of substances. For that reason, you cannot actually call natural gas environmentally friendly. But compared to the other three, natural gas is less harmful to the environment. The emission of NOx, sulfur compounds, fine dust and soot particles is lower and therefore better for the environment.
In Haarlem, buses have been running on natural gas for some time. Measurements have shown that the air quality has improved by as much as 50%. These measurements were carried out in areas where there are many buses.
Another environmental benefit is the distribution of the gas. This goes through the gas network that is already present everywhere. This while the other fuels are moved with all kinds of other vehicles. So a lot of energy is consumed in distributing it, while with normal gas it is simply pumped through the pipes.
Natural gas has more prospects for the future
If you look ahead, cars on CNG seem more rosy. It is not without reason that more and more car manufacturers are supplying models that are suitable for running on natural gas. Petrol, diesel and indirectly also LPG depend on oil, a finite fuel. Natural gas is also finite, but the natural reserves are much larger.
More important, however, is that cars on CNG can also run on biogas. This can be obtained from green waste and manure. Before you can ride it, it must be cleaned, but it can be used in the same engine. And as said, it is better for the environment, so for that reason alone it is more resistant to the increasingly strict requirements in that area.