Safety and environment | Environment · 76
75 · Safety and environment | Environment
Exhaust emissions.
The Cayenne models are all equipped
with the latest emissions technology. As
a result, they comply with the European
exhaust emissions standard, EU 5.
Whatever the class, every Porsche
combines high performance with com -
paratively moderate emissions. On the
Cayenne models, this is achieved using
advanced drive concepts – from petrol
and diesel engines to our parallel full
hybrid drive. This is further aided by the
rapid warm-up cycle of the catalytic
converters. The optimum operating tem -
perature is reached earlier so emissions
are reduced sooner when starting from
cold. On the petrol- engined and hybrid models,
another important feature is the use of
t win oxygen-sensor circuits. Each bank of
cylinders has a separate control system
which the engine management system
uses to establish the optimum amount of
fuel – for effective emissions control.
The exhaust-gas recirculation on the
Cayenne Diesel routes part of the exhaust
gas back into the combustion process,
resulting in lower peak com bustion tem-
perature and therefore lower nitrogen
oxide emissions. An oxidation catalyst
also forms an integral part of the process
along with a diesel particulate filter.
Porsche engines.
Performing for today – and the future.
Fuel and fuel economy.
Increasing performance while enhancing
fuel economy. The Cayenne comes in a
choice of three different drive systems,
each featuring state-of-the-art technol -
ogy for high efficiency and relatively low
fuel consumption. The petrol-engined
models already operate on fuels with
an ethanol content of up to 10 %. This
further improves the carbon dioxide
balance since the plants grown for the
production of biofuels absorb carbon
dioxide from the atmosphere. As you
can see, for the benefit of the environ
-
ment, we are continually working on
making our cars more efficient – as
well as compatible with alternative
fuels. While ensuring that they remain
one thing: a thoroughbred Porsche.
Fuel system.
We have also applied the highest stand -
ards to our petrol- engined models in
order to protect the environment from
fuel evaporation. The non-return fuel
supply system provides a considerable
reduction in vapour emissions. The lines
carrying vapour are made from multi-
layer plastics. A large active-carbon
filter and multi-layer plastic fuel tank help
reduce evaporation still further.
For fuel consumption, CO
2 emissions and efficiency class data, please refer to pages
15 0/ 151.
