LPG (Liquefied Petroleum / Propane Gas ), GPL ( gaz de pétrole liquéfié )

Industrial Neben-/Abfallprodukt

Liquefied propane, liquefied butane; Ratio of 95:5 to 30:70, usually offered as a " summer blend " 40:60 and " winter blend " 60:40

0.540 kg / l ( under pressure)

6.9 kWh / l = 12.8 kWh / kg = 46MJ/kg

105-115 RON (depending on the butane content )

1.740 to 1.780 kg / l ( depending on the ratio of propane / butane)


Petroleum gas ( LPG in the international parlance short, from English liquefied petroleum gas or GPL, from the French Gaz de pétrole liquéfié ) called for use in automotive internal combustion engines provided LPG, a variable mixture of butane and propane.

It is to be distinguished from compressed natural gas (CNG from English Compressed Natural Gas) and liquefied natural gas ( LNG from English Liquefied Natural Gas), which are also fuels.

  • 6.1 Venturi technology
  • 6.2 Teilsequenzielle systems
  • 6.3 Vollsequenzielle systems
  • 6.4 LPI systems
  • 8.1 Germany
  • 8.2 Europe
  • 8.3 Worldwide

Name and origin

LPG called liquefied gases such as ethane, propane, butane and mixtures thereof. These gases are liquid at room temperature under a relatively low pressure.

They fall in natural gas and oil production as "wet Bohrgas " to. Since collection, reconditioning and sales of the gases are inefficient, they are usually burned directly to the funding agency.

Furthermore, these gases are a byproduct of the refining of mineral oils (eg petrol, diesel). Again, the economic value of the gases was initially so low that they were torched. For many decades, the liquefied gases are used in various fields as an energy source and as a raw material in the chemical industry.

LPG as a fuel

LPG ( butane / propane) is used as a fuel for spark ignition engines. The first German gas filling station was opened in 1935 in Hannover in operation. Already in the 1970s it was widely used in Italy and the Netherlands.

It burns more environmentally friendly than gasoline. Even taking into account the principle-related excess consumption is harmful emissions of nitrogen oxides about 20 % of the gasoline combustion, CO2 emissions are reduced by about 15 % and unburned hydrocarbons by 50%. In addition, LPG ​​gases can be implemented by the better chemical usability at lower temperatures in automotive catalysts. LPG powered fork lift trucks may - in addition to natural gas forklifts - be operated as single vehicles with combustion engines in enclosed spaces. Diesel forklifts, however, emit soot and high amounts of nitrogen oxides.

In direct comparison with gasoline occurs, depending on the gas system (see below), a volumetric increase fuel consumption by 5 to 20% for LPG, due to the lower density and lower energy content per liter of liquid volume compared to gasoline. Gasoline has a density of about 0.76 g / cc, depending on the liquid mixing ratio from 0.51 to 0.56 g / cm ³. The 26 to 33 % lower density of LPG is partially compensated by the higher calorific value of 46 MJ / kg ( 12.8 kWh / kg) to 43.6 MJ / kg ( 12.1 kWh / kg). The perceived by the driver consumption can be even less if the gasoline launch, also required is not included in the calculation of consumption. For newer systems which are installed in direct-injection engines, depending on the built-up system does not start gasoline or gasoline is required during operation.

First was with LPG taxis (for example, all taxis in Istanbul and Bangkok ) and the National taxis and driving school cars in the late 1970s and in the 1980s in East Germany, and later in the private motor vehicle sector, in the 1980s in Austria very common due to favorable prices. Due to the higher taxation for private vehicles again uninteresting it was in Austria. However, Wiener Linien all buses converted to LPG drive because public Autogas remained tax-free.

Today LNG is established as fuel in most European countries. In Germany the number of cars and motorcycles is growing strongly. The reason is the current low tax on LPG. Under the Energy Tax Act is liquefied petroleum gas (LPG / LPG ) as a fuel taxed at 18 cents / kg ( = 9.74 cents / L) until the end of 2018, after which the rate is 40.9 cents / kg ( = 22.1 cents / L ) raised.

In Germany, the liters of LPG at the gas station currently costs 60-92 cents (as of May 2013) - where there is a slight north -south and west-east gradient here. The average price per liter is 77 cents (as of May 2013).

In Switzerland, LPG ​​is tax deductible since 2008. This has made it cheaper by about 0.25 francs / liter.

Vehicle conversion

An upgrading of the car to liquefied petroleum gas ( LPG) is relatively straightforward. Almost every vehicle with a gasoline engine can be for about 1150-3500 euros, depending on the number of cylinders, power output and to reach emission standard, rebuilt. The empty weight of an LPG system is about 40 kg.

Gas tank

For the tank, there are several installation options:

  • In the spare wheel well ( 34-94 liters), the spare wheel is then replaced by a breakdown spray or Runflatreifen.
  • In the trunk (30 to 250 liters ), usually in cylindrical shape.
  • Also underfloor tanks are possible. They are used mainly for passenger cars, where the spare wheel is located under the vehicle.

The range in gas mode, depending on tank size and fuel consumption 350 to 1000 km. When remodeling the petrol tank is retained, so that the vehicle can operate on either gasoline or LPG ( Dual-mode drive ).


The switching between petrol and LPG can be automatically or manually while driving. If the switchover automatically selected, this is usually done by a water temperature sensor. This ensures that is only switched when the engine is at operating temperature (or the small cooling water circulation around 35-40 ° C ) and the liquid does not freeze at the pressure reduction in the pressure reducer, which is why the pressure reducer must be heated. With the installation of the gas tank that is a significant range increase is connected.


For vehicles with an unfavorable material pairing between the alloys of valve and valve seat next to the unconditional adherence to the medium speed range is recommended that the additional incorporation of an additive in driving on LPG. The electronically controlled systems are complex because the additive dose is calculated and injected on the basis of engine load. Basically, the " 1% sample " applies. If at a driving distance of 1000 km, a gas consumption of 100 liters of gas is obtained, the optimum amount of additive mixed into 100 ml The consumption of additive is thus proportionate to the gas consumed linear. This implies that bigger is to LPG in accordance with the additive consumption of vehicles with higher consumption.

Just before the filled with an additive reservoir is empty, the metering pump will automatically take out of operation and sends a signal to the control unit. This then initiates the changeover to petrol mode. This prevents that is run in LPG operation without additive. In addition to the signal from the diode, which is placed on the dashboard warns the driver, a buzzer, that the additive reservoir is empty soon. So enough time to replenish the additive remains.

Electronically controlled systems give only to additives, if the driver is driving on LPG. The additive is thus only consumed when running on LPG.

Some equiment recommend the fitting of additive When Gern into the intake or the addition of an additive in gasoline and gas tank to reduce the wear on the valves and valve seats with modified fuel type and combustion conditions, since the combustion times at the same fuel-air mixture above those lie of gasoline. Thus, the exhaust valves are thermally stressed much more. In some vehicles, the valve seats are much less temperature-resistant than that of other vehicles (so-called soft -seat valve ), so that it may cause a motor damage in gas operation under certain circumstances. Higher combustion times and a resulting engine damage can be avoided from the outset, when a built-in gas plant in the upper load range corresponding to " fatter" (lambda value <1 ) is set. Every now and again to the consumption of LPG can be saved, and the mixture is adjusted to " lean". This often leads to engine damage or long-term to premature wear of valves. As an alternative to installing an additive Engers When there is gas plants, while the narrow small amounts of gasoline in gas mode. The need for the vehicle fuel load is adjustable.

Technology of LPG vehicles

With LPG powered car can be started either with petrol and then automatically switched depending on the built facility with a switch or gas operation to avoid any warm-up problems, or they start directly with LPG. A distinction is made between venturi systems, sequential systems and LPI systems.

The first two types of systems have in common that the liquid in the tank pressurized gas is supplied to the engine in gaseous form via an evaporator and pressure regulator. As the gas cools rapidly at similar cooling spray evaporation, the evaporator is heated with cooling water. For this reason, most car gas equipment cooling water temperature switch until around 30 ° C on gas to prevent icing of the evaporator at low outside temperatures.

In a two-year project, it is employees of the University of Applied Sciences of the Saarland ( HTW ) in Saarbrücken able to convert a small car on monovalent gas drive. The vehicle needs therefore to start no fuel and only pushes 90.9 grams of carbon dioxide per kilometer. The monovalency is achieved thanks to a liquid injection of car gas into the intake manifold at increased pressure up to 15 bar. Here, the LPG is a gas only after the injection by the relaxation. In most previous LPG installations, however, an evaporator is used, which must be brought to operating temperature only by the cooling water.

Since 1995, LPI facilities are offered. These systems promote by means of a fuel pump liquid gas under pressure in a loop, from where it is injected through metering valves in liquid form into the intake tract. By the absorbed heat for evaporation leads to a cooling effect of the intake air, depending on the gas flow rate reduces the intake by 5 up to 15 Kelvin. This results in a minor increase in performance (see turbo engine / charging air cooler ), respectively, obtained at a lower power loss in the evaporator equipment. To the combustion fuel and the oxygen contained in the air is required. Cold air contains more oxygen per volume than warm. In a conventional gasoline engine, fuel is injected in aerosol form, which requires virtually no volume. Gaseous fuels displace air and so reduce the amount of oxygen in the cylinder. For LPG theoretically 3 % of the air to be displaced in natural gas up to 10%.

The LPG combustion occurs at lower pollutant emissions and increased running smoothness. These effects are due inter alia to the high knock resistance of 105-115 octane and the homogeneous mixture formation. Gases are very fast and very evenly mixed with the combustion air in contrast to aerosols. By eliminating local defects or air - surplus formation of undesirable combustion by-products such as carbon monoxide, hydrocarbons or nitrogen oxides teil-/unverbrannten is suppressed.

Safety Technology

The security risks writes ADAC: " There is no evidence from practice, that for these vehicles is an increased safety risk, even from those countries where relatively many LPG cars are allowed. Show crash and fire tests that LPG cars are no more dangerous than comparable gasoline vehicles, " car gas tanks and their pipes are equipped with different security systems. Way of Füllleitungsanschluss is provided with a check valve in a pipe demolition prevents the escape of gas. The conveying conduit in the engine compartment is secured directly to the extraction tank to a solenoid valve, which closes immediately upon interruption of the power supply. When excessive pressure drop in the gas control unit interrupts the power supply to the solenoid valve. If in an accident no longer function the vehicle power supply, then the described solenoid valve due to the lack of power is always closed.

In the event of a fire, most tanks are to be examined at a pressure of (30 ... 35) bar ( bursting pressure approximately ( 60 ... 90 ) bar). Depending on the type of tank ( 1-Loch/4-Loch ) is either a separate pressure relief valve or a built- in multi valve pressure relief valve installed. This opens at a pressure of about (25 ... 28), thereby ensuring that the gas is vented controlled in case of fire and the tank can not burst.

Gas - air mixing methods

Venturi technology

The venturi technology is the oldest and cheapest solution. Here, a venturi nozzle is mounted in the intake duct before the throttle valve, which automatically admixed gas of the intake air that is required of a vacuum-controlled evaporator. The working principle is similar to a carburetor. This technique generally works well without any control, only the evaporator is set to a particular air-fuel mixture. Current controlled venturi systems nevertheless have a control device, which, inter alia, evaluate the presence of the lambda probe and the mixture is optimized by fine adjustment of the quantity of gas. Through the principle of conditional narrowing of the intake cross-section is expected at venturi systems with a slight loss of performance and consumption. Many air flow meter also work with older vehicles on the same principle (Source, Bosch K- Jetronic, air flow meter ) Here above all the experience of Umrüsters is required. In addition, there may be a back burning in the intake tract, with this technique. However, this known as Backfire phenomenon is no coincidence, it occurs only in case of faulty technique, eg by too lean or too rich mixture (analogous to the carburetor slippers ), on by defective or worn ignition systems or even with leaky intake valves. In the intake and / or in the air filter box built-in pressure relief valves which open in the case of the explosion to release all pressure damage can be prevented by Backfire. The (regulated ) Venturi technology is up to Euro 2 emissions standard (or even partly D3 ) suitable without loss of a tax bracket.

Teilsequenzielle systems

Teilsequenzielle systems use an electronically controlled metering valve, which injects the gas by means of a star-shaped gas distributor in the intake manifold of the cylinders. A cross-sectional constriction in the intake and therefore a loss of performance does not take place. Similarly, the Backfire risk is lower because the gas is fed immediately before the inlet valves and therefore not a relevant ignitable mixture is in the intake. These systems often have their own programmable characteristic field transducer for gas operation, the (eg camshaft position sensor ) and throttle position picks up only the signal of the lambda sensor, the speed of the vehicle. Therefore, even older vehicles to the emission standard Euro 3 with this system can be equipped. However, the teilsequenziellen system will become quite rarely offered. These are compared with a venturi significantly more expensive to purchase and to be programmed map set -consuming. Therefore, the price is often lower than the residual value of the vehicle providing to be retrofitted.

Vollsequenzielle systems

Vollsequenzielle systems ( state of the art in 2009 ) have a private metering valve per cylinder. These modern plants are often no longer have their own autonomous characteristic diagram computers but expect the determined from the fuel control unit injection period under gasoline into an equivalent Einblasdauer for gas around. Instead of Benzindüse a gas nozzle is operated, the control unit only determines the gas pressure and so that load-dependent adjustment factors. Therefore, upgrading and especially programming is simpler, but requires an existing sequential or gruppensequenzielle fuel injection. Modern vehicles since the mid-1990s already have this technology. The introduction of emissions standards Euro 3 and Euro 4 with EOBD ( Euro On - Board Diagnostic ) then made the sequential fuel injection mandatory. The Euro 4 standard is achieved easily or undercut (manufacturer's data ). In any case, an exhaust confirmation of the currently valid (or equivalent to the vehicle) is to require emission standard, otherwise a decrease (TÜV ) in Germany not (or only very difficult, so expensive) is to be obtained. Similarly, a certificate of the proper installation and tightness testing according VDTÜV 750 to demand etc.. (This is also in the aforementioned systems necessary, and when installed in foreign investments often not available. )

LPI systems

LPI is the abbreviation for Liquid Propane Injection and translates liquid propane injection, ie LPG injection. The sequential gas injection into liquid form is probably the latest (so-called ) fifth generation of LPG systems dar. This technique was already introduced in the early 1990s. These systems are compared to evaporation systems usually somewhat more expensive. The liquid gas pumps and tanks are relatively noisy and time were susceptible in the first series versions. The manufacturers advertise with combustion chamber cooling, since the LPG becomes liquid injected into the engine. Although under certain circumstances well before the inlet valves of the combustion chambers, the LPG is injected into the intake manifold and the LPG should evaporate already in the intake manifold, the charge air flow of the engine is still cool, thereby increasing the volumetric efficiency. This does not apply to systems with evaporators. Here, the cooling effect of the evaporating LPG seeps into the cooling water and can not be used to increase the volumetric efficiency.

The term LPI, the Dutch manufacturer Vialle can be protected under trademark law. The manufacturer ICOM therefore referred to the technique of liquid injection and JTG.

When Vialle - conditioning own map is generated by means of separate ECU - different fields should already be set.

The ICOM system uses LPG injectors that resemble the gasoline injectors in their characteristics. Thus, the injection timing of the fuel control device may be used. The gas control unit works as a toggle switch between petrol and gas injection nozzle. Only the gas injectors must be calibrated during installation. A complicated adjusting the gas control unit is omitted thereby as the evaporator systems. Further advantages are the non-existent maintenance costs for filter changes or readjustments of the software for running the model.


To fill a car gas vehicle at least three different connection systems are established worldwide. Depending on the country, a suitable adapter is required for use of the pump. This is the ACME connector ( " Europe Adapter", Screw ), the Dish connection ( "Italy Adapter", Dish Coupling) and the bayonet connector ( " NL- adapter "). Plans call for a single European port labeled Euronozzle.

Overview of the common connection systems:



In Germany it was the middle of 2013 already over 6,600 LPG filling stations. A saturation seems to be reached slowly in the price and supply situation. The growth rate of new LPG filling stations is steadily declining: Up to and including 2009, about 100 filling stations were opened per month, in the year 2010 about 40 and from 2011 for about 10 per month.


In several European countries (the Netherlands about 2100 gas stations, Belgium 650, Italy 3164, Poland 5000, the Czech Republic about 700, about 100 Slovakia, Romania 100, France 1700, UK 1400 ) and Turkey (around 10,000 ) are nationwide retail networks. The density of gas stations per capita in six countries ( Belgium, Czech Republic, Ireland, the Netherlands, Poland, Turkey ) is higher than in Germany.

In several other European countries, a basic supply for tourists and transit passengers is ensured:

  • Austria with 32 public filling stations (as of May 2013). As a fuel, LPG ​​is not encouraged in Austria on exemption from excise addition, because renewable fuels is given preference.
  • Switzerland with 52 known stations (as of May 2013)
  • Slovenia with 35 known stations ( mostly motorway service stations ) (May 2013)
  • Portugal with 95 known stations (as of May 2013)
  • Spain with 55 known stations, often in major cities (as of May 2013)


The largest share of consumption of all states of LPG has South Korea (22%), followed by Japan (9% ), Turkey ( 8%), Mexico ( 8% ), Australia ( 7%). Spread is also Autogas in Croatia (129 stations), Russia, Armenia, China, Thailand, Cambodia, Vietnam, USA and Canada.

Prices and costs

The prices of LPG in Germany amount to about € 0.50 to 0.94 per liter ( on average € 0.77 per liter, see Energy Tax Act ( Germany ) for taxation), foreign 0.30 to 0 € 99 per liter.

For the price compared to gasoline must be taken into account that the consumption increases liter for LPG operation by an average of 10 to 25 % as compared to the liquid gasoline has a much lower density and thus a lower calorific value per liter. Therefore, in comparison, the fuel costs between petrol / LPG and Super roughly be assumed that 60 to 70% of fuel costs. Otto engines are able to undercut the fuel costs of a corresponding Diesels in LPG operation. The observed during the winter development of fuel prices on the market usually tends more to a convergence of diesel and petrol price so that LPG compared to these types of fuel during this period will be cheaper. How fast does the conversion expects to LPG, depends on various factors such as consumption, price of conversion, annual mileage, the tax price trends and the vehicle type.

Unalloyed liquefied petroleum gas ( LPG) as a fuel is currently taxed in Germany with only 1.29 ct / kWh, diesel or gas oil ( sulfur content < = 10 mg / dm ³) but with 4.7 ct / kWh, gasoline ( sulfur content < = 10 mg / dm ³) even with 7.3 ct / kWh.

Comparison (LPG ) and natural gas (CNG) for automotive vehicles


  • LPG is a propane-butane mixture, the octane rating is, depending on the butane content, 105-115, usually 103-111 octanes in mixed gas in the ratio of propane to butane 60:40 or 104-107 octane RON at 40:60
  • CNG is composed mainly of methane ( about 84-99 volume %), the octane number is 120-140.


  • LPG is liquid stored at about 5-15 bar pressure (approx. 400 g of fuel per liter gross tank volume).
  • CNG is stored in gaseous form at about 200 bar (about 130 grams per liter of fuel pressure gas tank volume), and by a high-pressure regulator to 7 bar is reduced.

Engine power

Each gas (LPG and CNG) displaces air from the cylinder. This is for the combustion is less oxygen available. This means less power. In everyday relevant partial load range, the engine power by a more homogeneous and better cylinder charging, but even increase slightly. In supercharged or turbocharged engines the compressor, the power loss can be compensated by a higher supercharge pressure and thus a higher oxygen stuffing. The high octane rating of well over 100 of the LPG and CNG favors this circumstance. In classic naturally aspirated engines, however, must always be reckoned with both fuels with a fuel -dependent power loss.

  • LPG: A molecule of propane consumed in the combustion five oxygen molecules, a molecule of butane six and a half. Exist, depending on the gas composition up to 4% of the cylinder filling LPG. Old venturi systems or their nozzle ( only allowed to EUR 2 ), up 10 % power loss cause by additional throttling losses in the intake tract (only noticeable at full throttle ). With newer sequential evaporator systems is theoretically a performance loss of up to 3.8 % can be expected, but which is not noticeable in practice. A liquid -injection system cools the air in the intake system, whereby the filling cylinder is improved (analogous to conventional fuel injection upstream of the inlet valve). Therefore, it is often observed no measurable loss of performance or even a slight performance gain. This is further enhanced by the high octane number that allows a shift of the ignition timing in the direction "early". This is set by the knock sensor.
  • CNG: A molecule methane (methane is the main component of natural gas ) consumed in the combustion of two molecules of oxygen, natural gas has therefore significantly more (typically 12%) are metered into the cylinder, it will be displaced as a result, even more air oxygen. This oxygen is therefore not available for combustion and it is to be expected with a performance loss of just these 12 to 15 % (depending on Lastanfettung ). The power loss can just make it very noticeable in weak motorized vehicles and high Volllastanfettungen.

Carbon dioxide emissions

  • The LPG CO2 emissions are 1740-1780 g per liter depending on the ratio of propane / butane ( EIC Lower Saxony). LPG reduces CO2 emissions as compared to gasoline by about 15 %. Calculating method for propane: density of the liquid fuel about 500 g / L, molar mass of propane, 44 g / mol, the combustion produces CO2 to 3 per 44 g / mol. This gives 500/44 * 3 * 44 = 1500 g / L. Plus 30 % increase in consumption (see above) corresponds to a liter of super petrol by the energetically identical amount propane replaced CO2 emissions of about 2.0 kg per liter. With premium gasoline is expected to 2.32 kg / L (see [ fuel ] ). When butane is used, the result is due to the higher density and higher carbon content more CO2 per liter, but the additional fuel consumption decreases by the higher calorific value in return from. " On the decimal " exact data can not be specified by the temperature- dependent density of the liquefied gas and the seasonal change in the propane / butane ratio.
  • CNG reduces CO2 emissions as compared to gasoline by about 25 %. For engines which are optimized for CNG combustion, greater CO2 reduction by raising the compression and consequent increase in efficiency is theoretically possible. However, this assumes that the engine has been designed to meet the higher the gas compression operation. In standby operation occurs even with 100 - octane gasoline in return a higher consumption - more than if a super -Plus - optimized vehicle shall be driven with regular gasoline.


  • LPG can be retrofitted into recess tanks without trunk loss. Cylinder tanks with volumes up to 200 liters available; Recess tanks are offered depending on the dump size to about 60-95 liters. The installation of additional tanks is possible, eg in pickups or vans easily. The net tank volume is 80% of the gross volume. This is required for safety reasons ( expansion in hot vehicle ) and is secured by a shut-off valve in the vehicle. The test pressure of the tank equipment ( TÜV) is 40 bar, with normal operating pressures 8-15 bar. Since it is not to high pressure container at LPG tanks, a variety of tank shapes. However, are widespread cylinder and ring tanks.
  • CNG is transported in the luggage compartment housed cylinder tanks or, as in production vehicles become common under the floor or on the roof ( commercial vehicles) arranged tanks. CNG tanks have a test pressure of about 300 bar, the burst pressure is 600 bar. Because of the high pressure CNG tanks are not available as ring tanks or in special shapes.


  • LPG: Is currently at 6600 filling stations in Germany universally offered (as of mid 2013). Approximately 75 % of the LPG filling stations also carry gasoline and about 45 % are open 24 hours. In Brandenburg, the density of LPG filling stations is the lowest.
  • CNG: Is currently being offered at just over 900 filling stations in Germany (as of mid 2013). Approx. 81% of CNG filling stations also carry gasoline and approximately 65 % are open 24 hours. With the exception of North Rhine -Westphalia, the density of CNG filling stations is low.
  • General: Since June 2006, there is a legal basis for a nationwide uniform anticipation signs on motorways for LPG and CNG filling stations. At low gas station density, it is advisable to inquire before departure with respect to the gas stations located on the itinerary. Pure gas filling stations are often not staffed, so that payment is possible only by card ( debit card or debit card ). Unoccupied stations are usually slightly cheaper than regular gas stations.


  • LPG is transported as gasoline and diesel fuels usually on the road to the gas station and loaded so the traffic. However, the station operator is not necessarily linked to a regional gas supplier.
  • CNG, however, consists of natural gas and finds its way to consumers via pipelines. Gas stations get the natural gas from the network of local gas distribution companies; the compression on the tank pressure greater than 220 bar made ​​locally. Rural CNG filling stations without connection to a natural gas system are difficult or expensive to provide. Here provide biomethane filling stations a reasonable alternative dar.

Practical consequences

  • LPG as a fuel, although about 30 % effective expensive than CNG ( July 2008), however, the necessary modifications for retrofitting are due to the lower technical complexity in turn about 30 % cheaper and the achievable ranges generally higher than that of CNG. If a gasoline engine retrofitted to gas operation, so has often due to cost and space limitations on LPG.
  • CNG as fuel is effectively cheaper than LPG ( July 2008), however, requires higher pressure due to the thicker-walled and thus heavier tanks and allowed for retrofitting according to consumption ranges 240-300 km or less than that of LPG retrofit. If a vehicle is factory equipped with underfloor tanks, so ranges of over 650 km on a single tank can also be reached at CNG. Frequently new acquisition and conversion are supported by local gas utilities, the average funding amount is approximately 500 €.


Safety regulations

LPG storage tank systems are systems that require monitoring by the Operational Safety Ordinance, therefore it needs to before starting up and be rechecked at regular periods by an authorized body ( gas system check). The provisions of the Ordinance on Industrial Safety with regard to explosion protection must be observed.

Special measures are required when working below ground level ( cellars, etc. ), since LPG is heavier than air and may accumulate as a "lake". Also, floor openings ( manhole covers, hatches, basement exits) are included in the safety analysis.

The transport of liquid is controlled by the ADR - regulations.

Since 1998 has become established within most car park regulations of the individual federal states that it is in principle allowed to drive on LPG cars in underground car parks. Only in Berlin, Bremen and Saarland apply. However, sometimes prohibit the garage owner by the entrance signs. Care must be taken to the house rules of the garage owner. Even within Austria, the regulations are not uniform, since they fall within the competence of the provinces.

A car gas tank consists of an approximately 3.5 mm thick steel walls and is designed for a maximum working pressure of 20 bar. The safety assessment by TÜV write a test pressure of 40 bar before.

Safety valves also provide in the extreme event of a claim for a targeted blow or when exposed to heat - for example, in a vehicle fire - a controlled burning of the gas filling and thus avoid the risk of explosions. Important for the safe handling of the new technology, however, is compliance with the inspection intervals and guidelines.

Mobile containers

Increasingly With the proliferation of tank gas tank options come into circulation in the picture: Senior gas container in the form of a gas cylinder. They have the same size as the 11 -kg gas cylinders used in motor homes, balloons and a barbecue at parties and festivals, however, are technically identical to the vehicle mounted tanks. Especially for motorhome drivers they promise a significant increase flexibility, since the usual bottles are often not refillable abroad, on the other hand refuel at increasingly more points is possible.

Despite the technical compliance of the vessel with the gas tank but a refueling at a gas station in Germany is not permitted. These are according to § 2 para 12 No. 3 Operating instructions (air ) to the TRG (Technical regulations for compressed gases) bound specifically to the TRG 440, where calls § 4.1 that only tanks may be filled by TRG 380. In the TRG 380 it is then called, inter alia, § 2.1: " LPG tanks are perpetually linked with motor vehicles or other transportable installations and volumetrically filling pressure gas tank ... " This makes it clear that only use internal container, such as in image: Solid in a to see motorhome built- gas pressure vessel for external fueling, may only be filled. The background is that moving container, if you hold it at an angle, can be overcrowded.

In an action in 2010 flyers were similar to that in the reference shown distributed to gas stations. The gas station operators were thus re-sensitized and since it comes heaped on rejections of tank customers with such containers.

The station operator send sometimes but also those customers away, which meet with permanently installed equipment conditions. Justification is then often happens that the gas should not be used to operate an internal combustion engine. However, this is technically nonsense and non-tax justifiable. The fuel use is the use to which the highest energy tax rate is subject, namely, the full taxation pursuant to § 2 Paragraph 1 No. 8 and Section 2 No. 2 EnergieStG. If the energy product only, as in a motorhome, burned, on the other hand, a reduced tax rate pursuant to § 2 paragraph 3 No. 5 EnergieStG could be applied.

Pictures of Autogas