Document ID: chunk:federal_register_of_legislation:F2024L00447:reg:0:p44
Version: federal_register_of_legislation:F2024L00447
Segment Type: reg
Provision Reference: reg 0 (pt 44/57)
Character Range: 213609–216766

illustrated in Figure A8/2. The principle of the calculation is as follows: The RDE distance-specific CO2 mass emissions are not calculated for the complete data set, but for sub-sets of the complete data set, the length of these sub-sets being determined so as to always match the same fraction of the CO2 mass emitted by the vehicle over the applicable WLTP test (after all appropriate corrections e.g. ATCT are applied, where relevant). The moving window calculations are conducted with a time increment Δt corresponding to the data sampling frequency. These sub-sets used to calculate the vehicle on-road CO2 emissions and its average speed are referred to as 'averaging windows' in the following sections. The calculation described in this point shall be run from the first data point (forward), as shown in Figure A8/1.

              The following data shall not be considered for the calculation of the CO2 mass, the distance and the vehicle average speed in each averaging window:

              The periodic verification of the instruments and/or after the zero drift verifications;

              Vehicle ground speed < 1 km/h;

              The calculation shall start from when vehicle ground speed is higher than or equal to 1 km/h and include driving events during which no CO2 is emitted and where the vehicle ground speed is higher than or equal to 1 km/h.

              The mass emissions  shall be determined by integrating the instantaneous emissions in g/s as specified in Annex 7.

    Figure A8/1
       Vehicle speed versus time - Vehicle averaged emissions versus time, starting from the first averaging window
    Figure A8/2
    Definition of CO2 mass based on averaging windows
              The duration of the jth averaging window is determined by:

              Where:

               is the CO2 mass measured between the test start and time , [g];

                      is the reference CO2 mass (half of the CO2 mass emitted by the vehicle over the applicable WLTP test).

              During type approval, the CO2 mass reference value shall be taken from the WLTP test of the individual vehicle, obtained in accordance with UN Regulation No. 154, including all appropriate corrections.

              t2,j shall be selected such as:

              Whereis the data sampling period.

              The CO2 masses in the windows are calculated by integrating the instantaneous emissions calculated as specified in Annex 7.

              3.2. Calculation of window parameters

              The following shall be calculated for each window determined in accordance with paragraph 3.1.

              (a) The distance-specific CO2 emissions MCO2,d,j;

              (b) The average vehicle speed

              4. Evaluation of windows

              4.1. Introduction

              The reference dynamic conditions of the test vehicle are defined from the vehicle CO2 emissions versus average speed measured at type approval on the WLTP test and referred to as 'vehicle CO2 characteristic curve'.

              4.2. CO2 characteristic curve reference points

              The distance specific CO2 emissions of the