Constant development of technology comes with responsibility. We have to place more and more emphasis on the need to look for solutions that are effective and economical, as well as friendly to our planet. Reducing exhaust emissions in the automotive industry is currently a very important issue.

For this reason, we hear more and more often about the need to use ALTERNATIVE FUELS. All of us have heard this term, but many people find it difficult to identify which fuels are considered alternative. For the start, we should just ask:

What exactly are alternative fuels?

Are these unknown substances, just being developed by scientists? Are we talking about mysterious expensive alternatives to traditional fuels?

Alternative solutions are much closer to us than you might think. According to the definition of the European Union, alternative fuels are nothing else than:

“fuels or power sources which serve, at least partly, as a substitute for fossil oil sources in the energy supply to transport and which have the potential to contribute to its decarbonisation and enhance the environmental performance of the transport sector. They include, inter alia:

  • electricity,
  • hydrogen,
  • biofuels as defined in point (i) of Article 2 of Directive 2009/28/EC,
  • synthetic and paraffinic fuels,
  • natural gas, including biomethane, in gaseous form (compressed natural gas (CNG)) and liquefied form (liquefied natural gas (LNG)), andliquefied petroleum gas (LPG)”

So where can we find alternative fuels?

Alternative fuels - available on every gas station

At almost every fuel station! The most popular alternative fuel in Poland is LPG. So this is nothing new. It have been present on polish market for many years and power a huge number of vehicles. It is also very common in Germany, Italy, the Netherlands, South Korea, Turkey and the USA.

The second example of an alternative fuel – which we will refer to in this article – is CNG. Unfortunately, this one is much less popular for powering vehicles in Poland. However, there are countries where CNG is very popular as vehicles’ power supply – Brazil, Germany, India, Mexico, Nigeria, Spain and the USA.

What do these two substances have in common?

Both can be used in a gas installation dedicated to diesel engines – Fuel Fusion. The choice between two of them, compatible with different versions of our system, creates the need to make an important decision – which version of the installation should you choose for your truck, agricultural tractor, power generator or other diesel-powered machine?

Is it better to choose an installation compatible with LPG or CNG?

Unfortunately, there is no clear answer to this question. It is always worth familiarizing yourself with the properties of both alternative fuels, the possibilities they offer and their availability in the area where the machine will be used.

Alternative fuels and their role in environment

Diesel engines are considered quite environmentally unfriendly, despite the use of solutions in the latest models that significantly reduce the emission of harmful substances.

Who among us hasn’t heard the saying “Diesel must smoke”?

This sentence can be said about many older models of Diesel vehicles. Fortunately, the use of alternative fuel makes this sad joke no longer true, even in their case.

However, it is worth knowing that even partial replacement of diesel oil with gas not only brings significant savings in fuel costs, but also allows for a significant reduction in exhaust emissions. It turns out that the mixture of gas, diesel and air burns differently than just diesel and air – more here.

The addition of gas makes the diesel burn more completely and reduces huge part of emitted particulate matters (PMs) in the fumes. Gas has better combustion properties than diesel. As a result, its addition causes the mixture to burn at a higher temperature, thanks to which a larger amount of fuel is burned. Due to the fact that diesel oil is a hydrocarbon fuel and contains more carbon than LPG or CNG, reducing its consumption translates into a significant reduction in CO2 emissions.

Installing Fuel Fusion is a much cheaper solution than replacing the vehicle with a new one, powered by 100% gas. That is why this technology is the cheapest way to reduce the negative impact of diesel on the environment. Before doing so, it is worth considering which installation option to choose.

LPG – propane or propane-butane fuel

LPG – the liquefied petroleum gas, also called autogas (for automotive source of use) or propane-butane, is obtained during the refining of crude oil and from natural deposits. Initially, it was treated as waste generated during oil extraction. The situation changed with the invention of a pipeline, that is enabling the transport of LPG.

In trade we use name LPG for propane or propane-butane, it sometimes contains trace amounts of other hydrocarbons. Importantly, the proportions of propane and butane depend on a given climate zone and the current season.

In Poland, we get a different type of LPG in summer and a different one in winter. How do these gases differ from each other? The summer version of it has more butane, which has a higher boiling point. This fuel works best when it’s warm. Unfortunately, the properties of butane mean that the liquefied substance tends to turn into a gas at lower temperatures. For this reason, we do not use it in winter.

In the colder part of the year LPG contains more propane. It is a gas that is more resistant to lower temperatures and much more stable when frosts come.

Due to the fact that these are substances that can be relatively easily compressed until they condense and then stored in a liquid state, their storage, transport and use are very practical. These properties, combined with the relatively high calorific value, contributed to the popularization of LPG.

The main reason for the popularity of LPG is, of course, the price. It is much cheaper than diesel or gasoline. However, the advantages of LPG do not end there. Propane-butane is chosen by people who care about the good of our planet, because it leaves a small carbon footprint. Especially compared to diesel.

Although LPG is appreciated throughout Europe and all around the world. In 2022 were over 27 million of vehicles running on LPG. Most of them were from Turkey (4,9 mln), Poland (3,3 mln), Russia (3 mln) and Italy (2,8 mln). Many countries have policies encouraging the use of autogas, e.g. many school buses in the USA run on LPG and 95% of taxis in South Korea run on gas.

CNG – compressed natural gas

The name CNG is an abbreviation of Compressed Natural Gas. It is compressed to 20-25 MPa. The vast majority of it consists of methane, with the rest being nitrogen, propane and carbon dioxide.

Interestingly, methane is commercially available in two forms:
– compressed – as CNG,
– liquefied – as LNG.

The Fuel Fusion system can be installed with accessories that adapt the installation to operate with CNG or LNG. However, it is worth remembering that due to differences in cylinders’ prices and gas availability, the CNG installation is much more popular.

Due to its high price and low availability, CNG is not as popular as LPG among Polish vehicle users. The situation is completely different abroad. CNG is used quite widely among our western neighbours. There are 850 compressed natural gas stations in Germany and in Italy is over 1500.

Such extensive infrastructure results from the fact that CNG-powered vehicles are especially popular in Italy. The country, which many of us associate mainly with beautiful landscapes, wonderful culture and delicious food, also ranks first in Europe when it comes to the number of cars powered by compressed metha. They include both new vehicles adapted to run on CNG and modified units.

What is the difference between LPG and CNG?

Compressed natural gas is much more resistant to high pressure. Due to the fact that CNG is lighter than air, it is considered one of the safest fuels. It quickly escapes in the event of any leak, when LPG is lying on the ground and causing a hazard. This is why methane is safer than propane.

On the other hand, due to the higher pressure in the CNG cylinder, it poses a certain danger during installation. A careless LPG installer is exposed to frostbite caused by changes from liquefied to gaseous form. Although it is certainly not pleasant, these effects are minor if we take into account that an accident with the CNG installation may result in eg. the loss of a hand. The danger is much greater because the installation operates under high pressure (200 BAR), which means that an accident may lead to mechanical damage to the body. This is one of the reasons why we place great emphasis on safety issues when conducting Fuel Fusion assembly training.

High CNG pressure also causes other issues. The methane tank must be resistant to high pressure. Therefore, it has to be either heavier – if we choose the steel version – or much more expensive – if we choose a composite tank. There are 4 types of CNG cylinders.

Moreover, the properties of LPG make it much easier to provide appropriate infrastructure. The gas station must only be equipped with a tank and from time to time has to be visited by a tanker that will deliver the gas. The matter becomes more complicated in the case of CNG. Methane, unlike liquefied propane-butane, is not stored in a liquid state, but in a compressed form. As a result, its transport is much more difficult. It is not possible to transport CNG in a tanker. Instead, it must be sent through a pipeline. Some gas suppliers have tankers for transporting LNG, which have special compressors that allow them to refuel CNG tanks in this way. Due to the fact that LNG is more highly compressed and takes up less space than CNG, such a tanker can supply larger capacities of CNG tanks than it appears.

Availability at gas stations

One of the key elements that we should take into account when choosing the version of the Fuel Fusion installation is the availability of gas in a given country. This is quite an obvious issue – if we do not have something to fill the tank in our vehicle, the installation will not bring any benefits.

Therefore, we should start making decisions by checking the availability of gas in the area where our machine operates. In many countries, such as Italy, Belgium or Germany, we should not have a problem with refueling CNG and LPG. Both propane-butane and compressed natural gas are very popular, which is why they are available at most stations.

Unfortunately, not every country is so well prepared. For example, in Poland the situation is not as good as we would wish to. While the interest in LPG is huge and its availability is very high, CNG is a marginal product, so the availability is much worse.

LPG and CNG availibility

In practice, we can only buy CNG at several dozen public stations throughout the country. This situation does not mean that it is the wrong choice for vehicles traveling in our country. Some people have chosen this solution because they have access to the refuelling station and are very happy with it. We wrote about such a case here.

Fuel Fusion installations with CNG are also often chosen by transport companies whose vehicles travel across Europe. In countries such as Germany, Italy or the Netherlands, there is no problem with the availability of CNG. Some corporations operating in Poland have even set up a CNG station on their company premises.


Alternative fuels are a way to reduce our dependence on fossil fuels and our negative impact on the environment. They include a wide range of gas, synthetic and biofuels that can be a low-emission alternative to petroleum substances. That’s why it’s worth taking a closer look at them. Especially when we notice that they bring benefits not only to nature, but also to our pockets. Generating us significant savings.

Although both LPG and CNG work well as fuel, their properties differ. That’s why it’s worth getting acquainted with them before we decide to choose an installation that will help us change the functioning of our machine.