CNG (compressed natural gas) is the methane, the hydrocarbon of which the mix called natural gas is almost entirely composed by.
FAQ
LPG is the international acronym for liquefied petroleum gas. It is a crude refining product and a natural gas coming from the oilfields.
It has a complex composition but it is mainly made up by propane and butane.
CNG is an excellent fuel for controlled ignition engines, allowing to achieve great performances, low consumptions, very low polluting emissions and almost complete absence of carbon residuals into the engine. Thanks to its molecular structure, it can increase the energetic efficiency while reducing consumptions very much.
LPG gives vehicles excellent performances in terms of power, flexibility and engine good working, as well as it maintains the same engine oil properties for longer.
In Italy 3,420,776 vehicles supplied by alternative fuels and propulsions are travelling, of which 926.704 (2,41) have petrol-CNG bi-fuel engine. All bi-fuel vehicles are 8,88% of national car fleet (information provided by Consorzio Ecogas study centre)
In Italy 3,420,776 vehicles supplied by alternative fuels and propulsions are travelling, of which 2,309,020 (5,99%) have petrol-LPG bi-fuel engine. All bi-fuel vehicles are 8,88% of national car fleet (information provided by Consorzio Ecogas study centre).
With CNG systems, CO2 (carbon dioxide) emissions are reduced by 20% and particulate matter (PM10), main cause of air pollution, is zero. Find out more LPG OR CNG SYSTEM: WHICH TO CHOOSE
With LPG systems, co2 (carbon dioxide) emissions are reduced by 10%.
The total absence of sulfur and lead gases is accompanied by a significant reduction in carbon monoxide, hydrocarbons and nitrogen. Find out more LPG OR CNG SYSTEM: WHICH TO CHOOSE
CNG supplied by filling stations is measured in kilogrammes. 1 kg of CNG (year 2018) costs approximately 0,99 €/kg and corresponds to about 1,5 litres of petrol. In short, the use of CNG offers considerable economic advantages.
Assumed that 1 litre of LPG costs 50% less than 1 litre of petrol and LPG consumptions are about 20% more than petrol ones, it can be said that with a LPG converted vehicle you can have about 40% fuel savings compared to original petrol supply.
The total capacity (in litres) of cylinders installed divided by four gives with good approximation the equivalent CNG cubic metres contained into the tank.
For example, a 80 litres cylinder contains about 20 cubic meters of CNG.
Assuming to average 14 km to the CNG cubic metre (roughly equivalent to 12,5 km per petrol litre), the range should be at around 280 km.
1 litre of LPG costs approximately 50% less than 1 litre of petrol.
Calculates savings
The difference between two different fillings depends on both driving style and quantity of fuel supplied. The engine efficiency and the atmospheric conditions (air pressure and humidity) influence the engine performances too.
Being CNG not liquid, the fuel quantity supplied is not only a matter of tank volume (capacity of cylinders in litres) but also of pressure and temperature achieved at the end of filling; so, fuel quantity supplied can slightly change every time (the same happens in case of liquid fuels, but in a less sensible way).
The quantity supplied also depends on gas features (see next question).
It is in the nature of LPG to have a specific energy lower than the petrol one; consumption is approximately 20% increased.
It is quite normal that gas network supplies CNG with different composition and origin, even to the same filling station at different times. This can result in difference on kg supplied and amount to be paid. It should be said, however, that the heavier the gas, the bigger the energy content – and the longer the range.
This should be calculated on a case-by-case basis, starting from the dimension of tank, that is subject to 80% filling limitation for safety reasons, as per law requirements.
By way of example, a 60 litre tank can effectively stock 48 litre of LPG. Assuming to average 10 km to the LPG litre (roughly equivalent to 12 km per petrol litre), the range should be at around 480 km.
A CNG vehicle is filled by connecting the suitable nozzle to the car filling valve, generally situated into the engine compartment or next to the petrol filler.
In a modern filling station supplying CNG by weight, the refuelling can take 2 or 3 minutes on a mid-size vehicle (80 – 100 litres cylinder).
Different driving conditions and, sometimes, different LPG chemical composition can influence consumptions very much. It is therefore important to compare consumptions all conditions being equal.
Distribution network has today about 1.200 CNG stations in Italy, constantly growing, and approximately 3.700 CNG stations in 29 European countries.
A LPG vehicle is filled by connecting the suitable nozzle to the car filling inlet, which is different for some countries. Before moving to a foreign country, check if your refuelling point is the right one or buy the suitable adapter.
CNG system does not damage the right engine operation at all, on the contrary it extends its life.
Distribution network has today more than 4.000 LPG stations in Italy and approximately 8.700 LPG stations in 11 European countries.
OMVL provides approved CNG supply systems consistent with most of todays’ car engines on the market, so that you can convert to CNG almost all petrol vehicles (both the carburettor and the injection or supercharged ones) without incurring any technical problem. Ask anyway a OMVL installer for checking in details your engine and providing more specific information.
LPG system does not damage the right engine operation at all.
It depends on the kind of system and the installer labour organisation. On average, the conversion takes a few days.
OMVL provides approved LPG supply systems consistent with most of todays’ car engines on the market, so that you can convert to LPG almost all petrol vehicles (both the carburettor and the injection or supercharged ones).
Ask anyway a OMVL installer for checking in details your engine and providing more specific information.
In case of the modern systems the difference in performances driving the car is almost imperceptible.
It depends on the kind of system and the installer labour organisation. On average, the conversion takes a couple of days.
More than one only CNG cylinder can be installed on a car. So, by optimising the choice in accordance with the car boot, we can save space considerably without reducing the CNG total capacity too much.
In case of the modern systems the difference in performances driving the car is imperceptible (approx 2-3 % power loss).
CNG systems do not need any specific maintenance. Following the instructions indicated by the use and maintenance booklet of the system is suggested. In Italy, a specific tag required by the law (CNG cylinders fund committee) shows safety and validity information about cylinders installed on the car, necessary to refuel. CNG cylinders must be replaced after 4 or 5 years from its final test according to the compliant regulation.
Please check the related laws in force in your country.
Two kinds of LPG tank can be installed on a car: ring-shaped or cylindrical. The first one is usually installed into the spare wheel compartment (inside or outside the vehicle) so that luggage capacity is not affected. The cylindrical tank is usually installed into the car boot so that space for luggage is partially reduced according to the tank dimensions.
In Italy, CNG vehicles are not subject to any restriction concerning underground parking.
LPG systems do not need any specific maintenance. Following the instructions indicated by the use and maintenance booklet of the system is suggested. In Italy, LPG tank must be replaced after 10 years from its final test. Please check the related laws in force in your country.
Thanks to the very low polluting emissions, CNG vehicles can move freely into the historical centres during traffic restriction periods too, except for different indications.
In Italy, LPG vehicles can be parked in the above-ground lots and in the first basement of underground multi-level garages, thanks to the safety level achieved by modern conversion systems and required by regulation ECE/ONU 67-01 and lgs. Decree nov 22th 2002 of Ministry of Interior. Please check the related laws in force in your country.
The CNG conversion cost depends on many factors, such as the vehicle original supply (injection, direct injection), the kind of equipment installed (traditional, timed injection), the number of cylinders and so on.
All OMVL products are the result of years of research, experimentation and development processes. The quality insurance and management system specifically planned and applied assures the compliance of manufacturing processes to regulations UNI EN ISO 9001:2008 and ISO TS 16949:2009.
Gas systems complies with European and national laws in force. As well as CE regulations and norms concerning polluting emissions (Euro III, EuroIV, EuroV ed EuroVI) and electromagnetic compatibility.
Periodically, some economic measures are aimed at facilitating the CNG vehicles users. Visit the following links for more detailed information about incentives currently in force
Thanks to the very low polluting emissions, LPG vehicles can move freely into the historical centres during traffic restriction periods too, except for different indications.
The LPG conversion cost depends on many factors, such as the vehicle original supply (injection, direct injection), the kind of equipment installed (traditional, timed injection), the kind of tank.
Periodically some economic measures are aimed at facilitating the LPG vehicles users. Visit the following links for more detailed information about incentives currently in force
OMVL authorized workshops are able to install LPG systems on any model. Contact your nearest authorized dealer who will direct you to an authorized OMVL workshop: evolve your driving experience today!
OMVL authorized workshops are able to install LPG systems on any model. Contact your nearest authorized dealer who will direct you to an authorized OMVL workshop: evolve your driving experience today!