Emissions

When a vehicle is moving, the fuel or electricity consumption releases various pollutants into the atmosphere. In several countries, companies are subject to laws aimed at limiting global warming and improving air quality. Depending on the country's law, companies may be required to report what type and mass of pollutants they have released into the atmosphere.

In simple terms, emissions are calculated by multiplying fuel consumption values with emission factors.

To calculate emissions fuelType, emissionStandard and bioFuelRatio are relevant for combustion vehicles, electricityType is relevant for electric vehicles. For hybrid vehicles, all of them are relevant including the hybridRatio. The given averageFuelConsumption and averageElectricityConsumption can be considered, or they can be calculated using default values from HBEFA. In that case loadWeight, emptyWeight and totalPermittedWeight are also relevant to obtain proper results.

To learn more about how to validate CLECAT/DSLV guidelines to calculate CO2 emissions, please refer to the Emission allocation method concept page.
 

Emissions metrics

fuelConsumption

Fuel consumption represents the amount of fuel (kilograms or liters) that was consumed during the route.

bioFuelRatio

Biofuels cover all liquid, solid or gaseous fuels produced from biomass. They are usually blended with standard fuels (for example, E10 ethanol is a low-level biofuel blend of 10% ethanol and 90% gasoline). There is a large variety of biofuels either with diesel (B100, B5, B7, B10, B20, B99) or gasoline (E10, E15, E85). In many countries, a bioFuelRatio is required by the law. 

The default value of bioFuelRatio is 0. It can be specified in the request (engine.bioFuelRatio) from 0 to 100%.  

Please note that different rules may be applied in different countries depending on the legislation in force. These rules are likely to change over time. The user must therefore check for himself the legislation in force in the country in which the vehicle operates. 

To cover each case, the bioFuelRatio engine parameter needs to be filled. Here are a few examples:

• B5

B5 is a biodiesel blend of 5% biodiesel and 95% petroleum diesel

{
   engine:{
       engineType: "COMBUSTION",
       fuelType: "DIESEL",
       bioFuelRatio: 5
   }
}

• B99

B99 is the highest-level biodiesel blend, containing between 1 and 0.1 percent petroleum diesel

{
   engine:{
       engineType: "COMBUSTION",
       fuelType: "DIESEL",
       bioFuelRatio: 99
   }
}

• E10

E10 is an ethanol blend composed of 10% ethanol and 90% gasoline

{
   engine:{
       engineType: "COMBUSTION",
       fuelType: "GASOLINE",
       bioFuelRatio: 10
   }
}
 

CO₂-equivalent

Carbon dioxide is the best known greenhouse gas. However, there are other pollutants that have an effect on global warming. These gases can have a very significant warming power. The main greenhouse gases are carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O).

Based on the warming power of carbon dioxide, the Global Warming Potential (GWP) can be defined. The CO₂ has a GWP of 1, methane 25 and nitrous oxide 300. With the Global Warming Potential we can define a new metric called CO2-equivalent (CO2e) that represents the sum of the multiplication of all greenhouse gases by their Global Warming Potential.

Well to wheel, tank to wheel

The well-to-wheel metric refers to the emissions from the production of the primary fuel to the fuel consumed during the route. It includes production of the primary fuel, the transport of the primary fuel, the production of road fuel, the distribution of the road fuel and the consumption of this road fuel in the vehicle.

The tank-to-wheel metric only refers to the consumption during the route.

Example

The list of emission values is contained in RouteResponse.emissions. The emissions standards to be computed can be selected by using the results parameter.

This example shows how to request a route with the EMISSIONS_EN16258_2012_HBEFA standard and the EUR_TRAILER_TRUCK vehicle profile.

https://api.myptv.com/routing/v1/routes?waypoints=49.0133618,8.4277972&waypoints=48.8950289,8.6715602&profile=EUR_TRAILER_TRUCK&results=EMISSIONS_EN16258_2012_HBEFA&options[trafficMode]=AVERAGE

The result of the request above will look like this:

{
    "distance": 26853,
    "travelTime": 2082,
    "violated": false,
    "emissions": {
      "en16258_2012": {
        "fuelConsumption": 14.066087022979605,
        "co2eTankToWheel": 45.13996676845619,
        "co2eWellToWheel": 54.77658888756478,
        "energyUseTankToWheel": 606.9381299578937,
        "energyUseWellToWheel": 721.9013412034008
      }
    }
  }

Depending on the chosen standard, each emission item contains standard-specific emission values.

HBEFA

The Handbook of Emission Factors for Road Transport (HBEFA) was originally developed on behalf of the Environmental Protection Agencies of Germany, Switzerland and Austria. In the meantime, further countries (Sweden, Norway and France) as well as the JRC (European Research Center of the European Commission) are supporting HBEFA. HBEFA provides emission values, i.e. the specific emissions in g/km for all current vehicle categories (PC, LCV, HCV, buses and motorcycles), each divided into different categories, for a wide variety of traffic situations.

The first version (HBEFA 1.1) was published in December 1995, an update (HBEFA 1.2) followed in January 1999. Version HBEFA 2.1 was available in February 2004. The newest versions date are January 2010 (HBEFA 3.1), July 2014 (HBEFA 3.2), September 2019 (HBEFA 4.1) and January 2022 (HBEFA 4.2).

HBEFA calculation reports values for all global warming gases and other harmful substances. The internal process is independently certificated and therefore is independent of any external organizations.

HBEFA also provides the calculation of the fuel and electricity consumption considering defaults for the given vehicle and taking the actually driven roads (their classes and gradients) into account.

Influence of payload

When using a HBEFA-based method, the user can give the vehicle load information in order to have more precise emissions factors. The PTV Developer Routing API needs 3 values

• emptyWeight (the empty weight of the vehicle [kg])
• loadWeight (the weight of the vehicle's load [kg])
• totalPermittedWeight (the total permitted weight of the vehicle and load [kg])

Available emission standards

Try it in the Emissions code sample.

For detailed information on emission-related vehicle parameters see the Vehicle Parameters concept.