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IV. Ecological driving

Chapter 5: Driving

Operation of a vehicle

motor vehicle runs on a combustion engine. So fuel is needed for it to operate. When starting, fuel is sent into the engine.

Only part of the fuel burned and transformed into energy. The part of the burned fuel not transformed into energy is evacuated in the form of smoke towards the exhaust pipe.  This smoke contains gases that are toxic to humans and harmful to the environment.

What do the gases coming out of the exhaust contain?

Carbon dioxide (carbon dioxide): CO2

  • Result of combustion.
  • Greenhouse gas that stimulates global warming.
  • The more a car consumes, the more CO2 it emits.

Carbon monoxide: CO

  • Odorless gas that can also escape from poorly maintained boilers.
  • Dangerous in closed spaces, tunnels, garages or in queues because their concentration is higher (close your windows and turn off the exterior ventilation).
  • Symptoms include headaches and nausea.

Nitrogen oxides: NOX

  • Emitted during the combustion of fuels.
  • Includes, among others, nitric oxide (NO) and nitrogen dioxide (NO2).
  • Brownish gas with a pungent odor once in contact with air turns into nitric acid.

Nitrogen dioxide: NO2

  • Becomes nitrogen under the influence of sunlight and is one of the main constituents of smog and acid rain.


  • Due to imperfect combustion by a poorly adjusted engine.
  • The smallest of them are invisible to the eye and can cause cancer and lung damage.
  • Give off foul odors, damage buildings (blacken walls), land on roads and can make them slippery.

Different types of engines

LPG or LPG (Liquefied Petroleum Gas)

  • You can equip a petrol car by adding an LPG tank, the vehicle will have two tanks.
  • Produces slightly less CO2 and significantly less carbon monoxide and nitrogen oxide.

Gasoline (compared to diesel)

  • Emits little nitrogen oxide.
  • Rejects few particles.
  • Consumes more than diesel.
  • Emits more CO2.
  • More expensive cost.

Diesel (compared to gasoline)

  • Emits less CO2 and CO.
  • Rejects more particles.
  • Consumes less than gasoline.

      LPG is less polluting than gasoline and gasoline is less polluting than diesel.    

Low-sulfur diesel is less polluting         than   conventional diesel.

Red diesel         is   intended for domestic heating, it is  cheaper than road diesel but more polluting.

Hybrid vehicles         are   an  alternative to reducing emissions.  They have a combustion engine and an electric motor.

Electric vehicles         only   run on electricity and  therefore do not need fuel.  They are therefore  the most ecological.

CO2 emissions (gr/CO2 per km)

  • Less than 144 gr of CO2/km is ecological.
  • Equivalent to 144 g of CO2/km is moderately ecological.
  • Greater than 144 g of CO2/km is a polluting car.

Fuel consumption (litres/100km)

  • Less than 6 l/100 km: economical and ecological.
  • Equivalent to 6 l/100km: average consumption, economically and ecologically average.
  • Greater than 6 l/100 km high consumption and pollutes more.

What is driving consumption?

  • Choosing a  vehicle that is too old.
  • Not  respecting interviews.
  • Take unnecessary cargo.
  • Loading on the roof means  you lose aerodynamics.
  • Drive with the  windows open  (especially on the highway).
  • Heating, air conditioning, fires…
  • Too low tire pressure   .

Catalytic converter

 Allows you to complete the combustion of the fuels to be burned but also of carbon monoxide and nitrogen dioxide.

Particle filter

  • Reduces the level of pollution from diesel vehicles.

Low emission zones

These are areas where access is prohibited to the most polluting vehicles.

These are mainly old diesel vehicles which affect air quality and therefore health.

Which vehicles are affected?

  • Individual cars.
  • Vans.
  • Buses and buses.

What is the EURO standard?

  • It is a European environmental standard that a vehicle’s engine must meet.
  • The aim is to limit emissions of pollutants emitted by vehicles.
  • The higher the EURO standard of a vehicle , the lower its emissions will be.
  • We start from EURO 1 to EURO 6.

How do I know my EURO standard?

  • The EURO standard is indicated on the certificate of conformity and on the registration certificate.
  • If the EURO standard is not indicated, the date of first registration will be taken into account.

Shared cars

Subscription system 

  • Car rental by the hour, for a day or for longer periods.
  • Ideal solution for the person who needs a car occasionally.
  • These cars have reserved parking spaces.


  • Use a car to travel with others.
  • Allows you to optimize the use of a car.
  • Less traffic and pollution.

Sustainable mobility

  • To walk 2 km it takes 24 minutes.
  • Journey only 1 km, we do it on foot.
  • Journey of 1 to 10 km, by bike.
  • Beyond that, car or public transport.

I test my knowledge with questions

Chapitre 1: La réglementation