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CO2MPAS

CO2 Model for PAssenger and commercial vehicles Simulation

Transportroad transportvehicle simulationCO2 from light duty vehicles

overview

Transportroad transportvehicle simulationCO2 from light duty vehicles

main purpose

CO2MPAS is a vehicle simulation model for the calculation of CO2 emissions, energy, and fuel consumption from passenger cars and light commercial vehicles. It uses experimental data, retrieved from chassis dyno or on-road tests, to simulate the operation of vehicles under different operating conditions.

summary

CO2MPAS is a technology-based vehicle simulation model developed to estimate CO2 emissions, energy, and fuel consumption of passenger cars and light commercial vehicles. CO2MPAS was developed to calculate CO2 emissions of light duty vehicles over the NEDC test cycle and protocol,  using as input, data retrieved from tests performed in accordance with the new emissions type approval test, i.e.  WLTP (Worldwide harmonized light vehicles test procedure set out in Commission Regulation (EU) 2017/1151). The WLTP is the new and more realistic procedure for the emission type-approval of light duty vehicles which replaces the old and outdated NEDC procedure starting from 2017. The use CO2MPAS for the purpose of correlating CO2 emissions determined on the NEDC and the WLTP is set out in Commission Implementing Regulations (EU) 2017/1152 (light commercial vehicles) and 2017/1153 (passenger cars). The correlation of CO2 emission values is required to ensure a transition from NEDC based CO2 emission targets to targets based on WLTP emissions under Regulation (EU) 2019/631 setting out CO2 emission performance standards for light duty vehicles.

The CO2MPAS model is able to provide the difference in CO2 emissions under the two different test procedures, thus allowing the evaluation of an NEDC-based CO2 value. For doing so it uses of technical information concerning the technology configuration of a vehicle and the WLTP-based CO2 test results.

As a vehicle simulation tool, the application of CO2MPAS can be used for other purposes than the WLTP/NEDC correlation. Notably, the model can be used to simulate a large number of variations in vehicle configuration, type, characteristics and technology, allowing for a quick estimation of CO2 emissions from different types of light duty vehicles. In this way it might be integrated in i) a traffic simulation model to evaluate the effect on the overall energy/fuel consumption of policies and measures on the transportation system, or ii) to a fleet simulation model to evaluate the effect on energy/fuel consumption due to the introduction of new vehicle technologies.

CO2MPAS is also the simulation model that was used to calculate fuel consumption and CO2 emissions estimates provided by the JRC’s Green Driving tool, an on-line tool that calculates realistic fuel consumption values over specific routes depending on a vehicle characteristics (https://green-driving.jrc.ec.europa.eu).

model type

ownership

EU ownership (European Commission)
The model is being developed and maintained by the JRC.C.4 Unit who entirely owns the intellectual property of the tool.

licence

Licence type
Free Software licence

homepage

https://co2mpas.io/

details on model structure and approach

CO2MPAS is coded in PYTHON v3.4 computer language. It is based on vehicle longitudinal dynamics and has a modular architecture. It includes a series of predefined algorithms for simulating the operation of various components. It has the capacity to self-calibrate based on given experimental data.

model inputs

The primary use foreseen for the model is to correlate type approval CO2 emissions determined for light duty vehicles in accordance with the new WLTP test procedure set out in Commission Regulation 2017/1151 with the CO2 emissions determined pursuant to the old NEDC test procedure set out in Commission Regulation (EC) No 692/2008. The CO2MPAS model calculates CO2 emissions of light duty vehicles on the NEDC test procedure using as input data retrieved during the vehicle type-approval carried in accordance with the WLTP test procedure (Commission Implementing Regulations (EU) 2017/1152 and 2017/1153, hereinafter ‘Correlation Regulations’)). The correlation procedure and the model allows the transition from the NEDC to  the WLTP without affecting the CO2 targets defined in Regulations 443/2009 and 510/2011 (replaced since 1 January 2020 by Regulation (EU) 2019/631). The model requires an extensive list of inputs, as set out in Table 1 of Annex I to the respective Correlation Regulations, in order to ensure the required level of accuracy in the correlation of the CO2 emission values. The inputs include in brief:

  • type of fuel
  • engine/powertrain characteristics
  • gear-box characteristics
  • electric components
  • vehicle characteristics
  • specific technologies of the vehicle
  • the results of the vehicle tested under WLTP conditions.

A number of default input values are defined for vehicle classes for the model to be used for other purposes. For example it might be used to carry out scenario analyses on the effect on global CO2 emissions due to the introduction of specific vehicle technologies in the vehicle fleet, or to assess the effect of modifying some aspects of the vehicle type-approval test. In this case achieving high accuracy on the single estimation is not important and the default values can allow its use to derive aggregated statistics.

model outputs

CO2MPAS is able to provide fuel consumption, energy consumption and CO2 emissions for a vehicle following a predefined trajectory. Default simulation conditions are the NEDC and WLTP test procedures, for which it has been designed. 

model spatial-temporal resolution and extent

ParameterDescription
Spatial Extent/Country Coverage
EU Member states 27
Spatial Resolution
Entity
Vehicle
Temporal Extent
Other
Depending on trip/cycle duration <day
Temporal Resolution
Seconds
The simulation is carried out considering a frequency of 1Hz in the vehicle operations. Higher frequencies can also be accepted.