X
Frequently Questions About LPG & CNG

What is Lpg? What are its physical and chemical characteristics?

The term Lpg derives from the acronym Gas of Liquified Petrol. Lpg is a mixture of hydrocarbons, among which there are mainly the propane and the butane. These two gases pass to the liquid state as soon as they reach not very elevated pressures or low temperatures. Lpg is obtained by a process of Petrol refinement or directly by extraction and after simple processes of separation from natural gas or from petrol, with whom is found in oil deposits. 

What are the advantages of Lpg?

The advantages of changing from Petrol to Lpg are mainly of two types: economic and environmental. The economic advantage is due to the fact that the running cost of a Lpg car is inferior than the cost of a Petrol one. Furthermore the cost of Lpg, cheaper than Petrol, allows to amortize in a short time the initial cost of the system installation, so it’s possible to save money even if the car does’t run a lot of Kms. The environmental advantage is due to the fact that the Lpg doesn't contain a lot of polluting elements, such as carbon oxides and nitrogen oxides. Furthermore, it is not produced the particulate, a mix of microscopic particles produced from the combustion of diesel engines, which is one of the main causes of the atmospheric pollution of our cities, and composes in wide part the PM10. These ecological characteristics allow the Lpg cars to circulate even if in case of stop of the circulation due to the atmospheric pollution. 

How many Lpg vehicles are there in Italy?

The most recent statistics of the sector say that in Italy the Lpg vehicles are around 1.500.000 but also constantly growing.

Is it easy to refuel a vehicle with Lpg? How many Lpg refuelling stations are there in Italy?

It’s very easy because the Lpg refuelling stations are capillarily distributed along the national territory and they are around 2.400, of which around 250 on the highways.

What kind of autonomy has a Lpg converted vehicle?

The amount of kms run with a Lpg vehicle, with the same petrol capacity, is almost inferior of the 10-15% if compared to a Petrol system. It is possible to install a cylindrical tank (behind the back seat) till the capacity of 100 lt and a toroidal tank (usually installed in the spare wheel compartment) till the capacity of 75 lt. These are only nominal capacities: the real ones correspond to 80% of the nominal ones, so that 80 lt for a cylindrical tank and 60 lt for a toroidal one. In fact, on the multivalves is present a device safety that stops the passage of gas whenever the tank has been filled at 80%. These characteristics allow the vehicles, even those which have big engines, to run for a lot of Kms.

How is a Lpg vehicle refuelled?

A Lpg vehicle is refuelled hooking up the dispensing nozzle of the Lpg pump to the filling valve of the car, which is different from country to country, even if in Europe the most common are the Italian, the German and the Holland type. Before beginning a trip in a foreign country, it’s better to control if you have the suitable filling valve. In the most recent systems it is possible to install, if you have enough space, the filling Lpg valve in the petrol door. The average refuelling pressure is around 8 bar. 

What is the power loss of a Lpg vehicle?

In case of the timed sequential injection systems Emmegas HPI-07, the different performance of the vehicle (loss of power) is around 2-3% and therefore the driveability of the car is the same.

Does the space in the luggage compartment decrease, after the installation of a Lpg system?

It depends on the type of the tank that is used. In case of toroidal one, which is installed in the spare wheel compartment, it is possible to safeguard entirely the luggage compartment of the vehicle. On the contrary, a cylindrical tank is generally positioned in the luggage compartment, just behind the back seat, and therefore it limits the carrying capacity according to its dimensions. 

Is it allowed to park a Lpg vehicle underground in public garages? Are there any other restrictions?

All the vehicles with a Lpg conversion kit installed after the year 2002 (and therefore in compliance with the Regulation ECE/ONU 67/01) can park until the first floor of underground garages, also if it communicates with a lower floor. On the contrary, the vehicles with a Lpg conversion kit installed before this date, and so not complying with the safety systems of the Regulation 67/01, can always park in garages just in the outside floor, not communicating with the underground floors. The conformity to this regulation is so indicated in the car logbook “INSTALLATION EQUIPPED WITH SAFETY SYSTEMS ECE/ONU 67.01”. For what it concerns the transport by sea with ferryboats, the Lpg vehicles have to be declared when you book your travel. On the contrary, for air and railway transport there are no prohibitions, as for the transit in galleries, tunnels or viaducts.

The vehicles which do not comply with the ECE/ONU 67/01, which law have to consider? 

In this case, they have to consider the legislative decree of 1st February 1986, that allowed the Lpg vehicles to park only in the outside floors not communicating with underground floors. This doesn’t mean to renounce parking in underground garages: it’s possible to conform the Lpg system to the New European Regulation with no so big costs and in a short time.

Are the Lpg systems dangerous?

All the systems, once installed, have to be tested at the provincial office of the department of the Ministry of transports. The tanks, together with the multivalves and other mechanical components, have to pass severe tests of resistance with very high pressures if compared to those of exercise. Furthermore, the new European Normative schedules effort tests on the materials, together with compatibility tests of the rubber parts to the hydrocarbons. Finally, in case of accident, the tank becomes an hardening element for the passanger compartment. These norms guarantee elevated safety standards, also superior than petrol and diesel systems.

What is Cng, what are its physical and chemical characteristics?

Cng (the acronym for compressed natural gas) is the simplest hydrocarbon, not derived by processes of petrol refinement, whose molecule is composed by an atom of carbon and four of hydrogen (CH4). It’s also the principal constituent of what is known as natural gas, that you can extract from oil fields and also from the decomposition of some organic substances, and therefore is classified as biogas.

What are the advantages of Cng?

The advantages of changing from Petrol to Cng are mainly of two types: economic and environmental. The economic advantage is due to the fact that the running cost of a Cng car is smaller than the cost of a Petrol one. Furthermore the cost of Cng, smaller than Petrol, allows to amortize in a short time the initial cost of the system installation, so it’s possible to save money even if the car does’t run a lot of Kms. The environmental advantage is due to the fact that Cng doesn't contain a lot of polluting elements, such as carbon oxides and nitrogen oxides. Furthermore, it is not produced the particulate, a mix of microscopic particles produced from the combustion of diesel engines, which is one of the main causes of the atmospheric pollution of our cities, and composes in wide part the PM10. These ecological characteristics allow the Cng cars to circulate even if in case of stop of the circulation due to the atmospheric pollution.

How many Cng vehicles are there in Italy?

The most recent statistics of the sector says that in Italy the Cng vehicles ( cars, buses and trucks) are around 775.000

Is it easy to refuel a vehicle with Cng? How many Cng refuelling stations are there in Italy?

The Italian Cng filling stations net, even though not wide as the Lpg one, is growing and today it counts around 960 Cng filling stations, of which around 30 situated on the highways. 

In Italy, Cng is sold in Kilos. How much petrol is equal to a kilogram of Cng?

A kilogram of Cng (at the pressure of 200 bar and with a temperature of 20°C), equals to around 1,64 liters gasoline.
 

How is a Cng vehicle refuelled?

The refuelling of a Cng vehicle is carried out by a filling valve situated on the vehicle, generally in the engine compartment or near the petrol refuelling point, and through a connection bringing the Cng in pressure to the cylinders (normally situated in the luggage compartment).The Cng refuelling is done at the pressure of 200/220 bar.

What kind of autonomy has a Cng converted vehicle?

In case of the timed sequential injection systems Emmegas HPI-07, the different performance of the vehicle (loss of power) is around 10-12% because of the different filling volume of the Cng in the engine cylinders. However, regarding driveability, you can get better results by fitting a timing advance processor.

Does a Cng system need a particular maintenance?

There is no need of a particular maintenance; we recommend to do periodical check according to the expiries scheduled by the car manufacturer. For what it concerns the gas system, you have to follow what is written in the "User Manual". 

Are there any security restrictions for Cng vehicles?

There are no restrictions for Cng vehicles; they can park underground in public garages, too. 

Does the space in the luggage compartment decrease, after the installation of a Cng system?

Yes, it does, because the cylinders must be installed in the luggage compartment, behind the back seat. Furthermore you have the possibility to install more than one cylinder. 

Is it dangerous to transport a Cng cylinder in the luggage van?

No, it isn’t. In fact the cylinders are submitted to hard tests, both during their first homologation and during all their life. The cylinders must be sufficiently strong to face test pressures of 300 bar and working pressures of 220 bar. For the Italian law, all the Cng systems, once installed, have to be tested at the provincial office of the department of the Ministry of transports. Moreover, also the other mechanical components have to pass severe tests of resistance with very high pressures if compared to the working ones. Furthermore, the new European Regulation schedules effort tests on the materials, together with compatibility tests of the rubber parts to the hydrocarbons. All these tests, guarantee elevated safety standard, also superior than petrol and diesel systems.

What legal obligations Cng cylinders must respect?

For the Italian law, every five years CNG cylinders must be submitted to a test made by G.F.B.M. (Italian acronym for CNG Cylinders Fund Administration). This operation is totally free of charge (except for vehicle assembly and disassembly), and it’s carried out in order to verify cylinders state and efficiency, and assure the best working safety of the vehicle with a CNG system. On the contrary, if the cylinders are approved according to the ECE/ONU 110 Regulation, the test must be done every four years, according to the Italian law n° 3171 of September 2005.

What is the average cost to convert a car from petrol to Cng?

The cost of the transformation depends on many factors, such as the original type of the vehicle (carburetor, single point injection, multipoint injection), the type of system installed (traditional, electronic with lambda control, timed sequential injection), the number of the cylinders and the devices installed. To make an example, the prices agreed with the Italian National Association of Cng System Constructors are as follows: · 1.400,00 € for a carburettor or EURO 0/EURO 1 injection vehicles; · 1.750,00 € for injection vehicles with carburetion control EURO 0/EURO 1; · 2.400,00 € for catalytic vehicle with timed sequential injection system EURO 3/EURO 4 To such indicative values it must be added: · around 100 € to install the Timing Advance Processor · around 130 € for the administrative matters and the updating of car logbook. 
About Us

Emmegas is an Italian company leader in the field of automotive alternative fuel solutions.

Founded by Medardo Landi in 1993 since the beginning, the company set clear and precise targets for a progressive and steady growth in the 'autogas' market. 

More information
Latest News
Contacts

For any further information don't hesitate to contact us. We will answer as soon as possible.

Address : Via dell'Industria 20 - 42025 Cavriago (RE) Italia

Telephone :  +39 - 0522 - 246500

Fax : +39 - 0522 - 246502

E-mail : sales@emmegas.net

Web : www.emmegas.net