19-05-2014, 04:52 PM
Automotive LPG and Natural Gas Engines
Automotive LPG.pdf (Size: 200.58 KB / Downloads: 147)
TECHNOLOGY STATUS AND PERFORMANCE
Internal combustion engines running on liquid
petroleum gas (LPG) and natural gas are well-proven
technologies and work much like gasoline-powered
spark-ignition engines [18]. They are normally used as
spark-ignition engines for bi-fuelled (gasoline/CH4)
cars, but have also been used, for example, in
compression-ignition (i.e. diesel-type) engines for
heavy-duty vehicles. Both LPG and NG is not used
alone, but always in bi-fuel vehicles, in combination with
gasoline. In bi-fuel vehicles two fuels are stored in
separate tanks and the engine runs on one fuel at a
time1. Bi-fuel vehicles have the capability to switch back
and forth from gasoline to the other fuel, manually or
automatically. In the past most bi-fuel vehicles were
derived from native gasoline vehicles by adding a tank
and an electronic injection regulation system for the
alternative fuel. In recent years the availability of ‘native’
bi-fuel vehicles has increased; they have two separate
tanks and two alternative injection regulation programs.
CURRENT COSTS AND PROJECTIONS
In
general, in the UK, the additional purchase price or
conversion cost of a new LPG car or car-derived van
is around €1130 for a 4-cylinder vehicle, €1300 for a
6- cylinder vehicle, €1528 for an 8-cylinder vehicle and
€2740 for heavy duty vehicles. In the US, the average
cost of converting a light-duty vehicle from gasoline to
propane ranges from €2990 to €8960. [11, 14]
POTENTIAL AND BARRIERS
It should be noted
that the use of LPG as an automotive fuel varies very
widely within a country and from one country to another,
depending on the cost and availability of the fuel in
relation to alternative fuels, notably gasoline and diesel.
Major drivers for LPG and natural gas vehicles
deployment are increasing oil prices, the availability of
refuelling infrastructure, and governmental support (e.g.
tax credits on capital investments). An evaluation of
global market potential for LPG and CNG vehicles and
alternative fuels reveals that the number of LPG and
CNG kits sold globally was 2.9 million in 2006. It is
estimated that they will reach 8.0 million by 2012. LPG
kits will continue to dominate the market in the EU,
Russia, Turkey, and other countries. India and Iran
accounted for 20% of global sales of CNG kits in 2006.
While aftermarket sales of LPG and CNG kits currently
hold more than 85% of global kit sales, original
equipment manufacturer (OEM) kit sales will steadily
increase to reach more than 27% of the total number of
units sold by 2012.