DRAFT - formal adoption and publication of the final report by UBA is expected soon. Federal Environment Agency, Germany FKZ

Transcription

1 ENVIRONMENTAL RESEARCH PLAN OF THE FEDERAL MINISTER FOR THE ENVIRONMENT, NATURE CONSERVATION AND NUCLEAR SAFETY - Air Pollution Control - Federal Environment Agency, Germany FKZ "Future Development of the EU Directive for Measuring the CO 2 Emissions of Passenger Cars - Investigation of the Influence of Different Parameters and the Improvement of Measurement Accuracy - Final Report, 14 December by Helge Schmidt Ralf Johannsen Institute for Vehicle Technology and Mobility Drivetrain / Emissions Passenger cars / Motorcycles By order of the Federal Environment Agency, Germany

2 - 2 - Index 1 ABBREVIATIONS 3 2 INTRODUCTION 4 3 PROJECT IMPLEMENTATION Investigation Programme Selection of Test Vehicles Performance of the Investigations 14 4 TEST RESULTS Test Vehicle VW GOLF 1.4 TSI Test Vehicle OPEL CORSA 1.2 L Test Vehicle BMW 320i Test Vehicle PEUGEOT 207 HDI Test Vehicle AUDI A4 AVANT TDI Test Vehicle DAIMLER C 200 CDI 32 5 EVALUATION Parameters affecting CO 2 measurements BASIC MEASUREMENT INERTIA MASS DRIVING RESISTANCE INFLUENCE OF THE DRIVER AMBIENT CONDITIONS BEST CASE GEAR SHIFTING START-STOP SYSTEM BATTERY STATE OF CHARGE 46 6 RECOMMENDATIONS FOR THE FUTURE DEVELOPMENT OF THE EU DIRECTIVE 47 7 SUMMARY / CONCLUSION 52 8 REFERENCES 54

3 - 3-1 Abbreviations A4, A5 4-speed or 5-speed automatic transmission CI compression ignition CO carbon monoxide CO 2 carbon dioxide DSG Direktschaltgetriebe (dual-clutch transmission) EUDC Extra Urban Driving Cycle Euro 1 Type approval in accordance with Directive 91/441/EEC Euro 2 Type approval in accordance with Directive 94/12/EEC Euro 3 Type approval in accordance with Directive 98/69/EC Euro 4 Type approval in accordance with Directive 98/69/EC, more stringent requirements compared with Euro 3 (e.g. reduced limits, -7 C test for using petrol engines) Euro 5 Euro 6 type approval in accordance with Regulation (EC) No. 715/2007 on type approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and on access to vehicle repair and maintenance information, Official Journal of the European Union FC Fuel consumption GSI Gear shift indicator HC Hydrocarbons KBA Kraftfahrt-Bundesamt (German Federal Office for Motor Traffic) KraftStÄndG Kraftfahrzeugsteueränderungsgesetz (German Motor Vehicle Tax Reform Act) of 18 April 1997 KV Kraftstoffverbrauch (fuel consumption), calculated from carbon components of exhaust gases M5, M6 5-speed or 6-speed manual gearbox NEDC New European Driving Cycle NEFZ Neuer Europäischer Fahrzyklus (NEDC) in accordance with Directive 98/69/EC NO nitrogen monoxide NO X nitrogen oxides SMK Schwungmassenklasse (inertia mass class) UBA Umweltbundesamt (Federal Environment Agency) UDC Urban Driving Cycle = inner city part of NEDC

4 - 4-2 Introduction Global warming has focussed the debate on the environmental compatibility of road traffic on carbon dioxide emissions. Since the beginning of the industrial revolution the CO 2 concentration in the atmosphere has risen by about 30%. With a share of 12 % in anthropogenic CO 2 emissions in Europe, road traffic is one of the main causes of global warming. Limited oil resources and the resulting rises in fuel prices have made fuel consumption a key criterion for new car purchase decisions. The EU has undertaken to reduce greenhouse gas emissions by at least 20 % by 2020 compared with the figure for The Commission has developed a strategy for reducing carbon dioxide emissions caused by. Regulation (EC) No. 443/2009 for the reduction of the CO 2 emissions of new was adopted on 23 April The objective is to reduce average CO 2 emissions to 95 g/km by The aim for 2012 is to reach average emissions of 120 grams of CO 2 per kilometre. The target for average CO 2 emissions determined in accordance with Regulation (EC) No. 715/2007 is 130 g/km. The gap between the target of 120 g/km for 2012 and the limit of 130 g/km on CO 2 emissions determined during type approval testing is to be bridged by additional measures such as the increased use of fuel from renewable sources, an upper limit on the rolling resistance of tyres and the use of gear shift indicators for consumption-optimized gear-shifting. Regulation (EC) No. 443/2009 provides for a CO 2 limit of 130 g/km for new passenger cars to be introduced step by step by The limit is to be met by 65% of the new vehicles of each manufacturer in 2012, 75 % in 2013, 80 % in 2014 and 100 % in For manufacturers whose average fleet emissions exceed the target set, it is proposed to introduce an "excess emissions premium" for each additional gram of carbon dioxide emissions from 2012 onwards. By 2019, this premium is to be increased to 95 euros per gram. The amount of premium payable is to be determined on the basis of average fleet emissions. This value will be calculated on the basis of the number of new registered and the CO 2 emissions measured during type approval testing. Figure 2.1 shows the average fuel consumption of all new vehicles registered in Germany calculated from the CO 2 emissions determined during type approval testing. The diagram clearly shows that the efficiency of the new vehicle fleet has been significantly improved over the past few years. The growing number of vehicles equipped with compression ignition engines, especially in the case of larger, heavier cars, has played a key role in reducing average fuel consumption.

5 - 5 - Average fuel consumption [l/100km] % 60% 50% 40% 30% 20% Percentage of diesel cars [%] 1 10% % Figure 2.1: Average fuel consumption and share of diesel vehicles in new passenger car registrations in Germany (Source: BMVBS, KBA) This trend continued in The average CO 2 emissions determined for newly registered in Germany in 2009 over the NEDC were g/km. In this context, it should be noted that many small vehicles with low fuel consumption were sold in Germany in 2009 as a result of the German vehicle scrappage scheme. A slight increase in the average CO 2 emissions of newly registered vehicles is therefore to be expected in In view of the average CO 2 emissions of g/km for the first half of the 2010, the automobile industry will need to make considerable efforts to reach the targets set by the European Commission. The basis for the determination of the CO 2 emissions of and light commercial vehicles is Regulation (EC) No. 715/2007. During type approval testing, exhaust emissions are measured on a dynamometer over the New European Driving Cycle (NEDC). The fuel consumption is calculated from the emissions of exhaust gas components (CO 2, CO and THC) containing carbon. No limits on carbon dioxide emissions or fuel consumption are defined in the type approval procedure. The CO 2 emissions and fuel consumption values declared by manufacturer must not exceed the results of type approval testing by more than 4 per cent. The CO 2 emissions and the fuel consumption determined during type approval are influenced by a number of different factors. The mass and driving resistance of the test vehicle play a key role. Other factors such as vehicle preparation before testing may have a significant impact on the test results. Especially the test room temperature and the state of charge of the vehicle battery must be taken into consideration.

6 - 6 - The engine speed and the gear shift points have a crucial effect on fuel consumption. The driving cycle defined by the Directive includes fixed gear shift points for vehicles equipped with internal combustion engines and manual gearboxes. In contrast, the manufacturer can define gear shift points for vehicles using automatic transmissions and hybrid vehicles with gear shift indicators. This allows such vehicles to be operated at lower engine speeds and to reach lower fuel consumptions over the driving cycle. In view of the rising importance of CO 2 emissions and fuel consumption for consumer's purchase decisions and the excess emissions premiums proposed for manufacturers, the conditions for type approval testing must be defined in such a way that the test results are reproducible and realistic. This research programme investigates the effects of various parameters on the results of type approval testing. /1/, /2/, /3/, /4/, /5/, /6/, /7/, /8/

7 - 7-3 Project Implementation 3.1 Investigation Programme This research programme investigated the effects of various factors on the carbon dioxide emissions and fuel consumption determined during type approval testing. For this purpose the CO 2 emissions and the fuel consumption of 6 were determined with reference to the variations in the different parameters allowed by the Directive. The first step was to measure the exhaust emissions and fuel consumption of the test vehicles as delivered. The various parameters were then varied in order to determine their influence on the test results. The measurements focussed on the vehicle mass used for the measurements, the load setting of the dynamometer, the driving cycle with the tolerances permitted and shift points used, vehicle preparation and the influence of battery charge state, The following factors were investigated: variation of the inertia mass variation of the driving resistance on the dynamometer influence of the driver, by using the tolerances in the driving cycle preparation of the test vehicle optimized measurement variation in gear shifting automatic start-stop function partially discharged starter battery ( low battery ) The various measurements and the conditions taken into consideration are presented and explained in the following paragraphs. Basic measurements: Initially, the exhaust emissions and the fuel consumption of the vehicles in delivery condition were measured on a dynamometer and the test results were compared with the values declared by the manufacturers. The measurements were based on the inertia mass and the load setting used for type approval testing. During testing the driving cycle was followed as closely as possible. Before the tests were started, the temperature of the vehicles was set to 22 C and the battery was fully charged. /9/ The following parameters relevant to the current type approval procedure were varied: Inertia mass: A key parameter for determining CO 2 emissions and fuel consumption is the equipment of the test vehicle and the vehicle mass. In Directive 92/21/EEC, Annex II, Art. 2.3 the

8 - 8 - mass of load in excess is declared as the the difference between the technically permissible maximum laden mass and the mass in running order increased by the mass of the conventional load. The mass of the load in excess may include the mass of optional equipment, e.g. sunroof, air conditioning, coupling device. Many manufacturers take advantage of this definition and determine the CO 2 emissions using a lower vehicle mass without consideration of this optional equipment. To evaluate the influence of the vehicle mass on CO 2 emissions, the inertia mass was increased by 2 classes in comparison to the value used during type approval testing. This means an extra weight of about 220 kg (500 lbs) due to better equipment. Within the framework of this programme, the measurements with increased inertia mass compared to the base test can be seen as representing a worst case scenario. Table 3.1 shows the relationship between unladen mass, reference mass and inertia mass of the test vehicles. /10/, /11/ Unladen mass [kg] Reference mass [kg] Inertia mass [kg] [lbs] 1,055 < UM 1,165 1,080 < RM 1,190 1,130 2,500 1,165 < UM 1,280 1,190 < RM 1,305 1,250 2,750 1,280 < UM 1,395 1,305 < RM 1,420 1,360 3,000 1,395 < UM 1,505 1,420 < RM 1,530 1,470 3,250 1,505 < UM 1,615 1,530 < RM 1,640 1,590 3,500 1,615 < UM 1,735 1,640 < RM 1,760 1,700 3,750 1,735 < UM 1,845 1,760 < RM 1,870 1,810 4,000 1,845 < UM 1,955 1,870 < RM 1,980 1,930 4,250 Table 3.1: Unladen mass, reference mass and inertia mass in accordance with ECE Regulation No. 83 (excerpt) Driving resistance: The driving resistance of the test vehicle has a decisive impact on the results of exhaust emission tests for type approval. To determine the driving resistance of a vehicle, the energy change during coast-down is measured on a test track. The test vehicle is first accelerated, then the gearbox is shifted to neutral and deceleration times for a number of different speed intervals are measured. The driving resistance of the vehicle at different speeds can be determined from these coast-down times. The vehicle mass, the rotating masses, resistances in the power train, the rolling resistance and the aerodynamic resistance of the vehicle are determined under realistic driving conditions. For later tests, the dynamometer is adjusted to obtain the same deceleration times as on the test track. This allows the driving resistance measured under real driving conditions to be simulated on the test track. For the setting of the driving resistance curve on the dynamometer, tolerances of ±5 % in the higher speed

9 - 9 - range (120 km/h to 40 km/h) and ±10 % in the lower speed range (20 km/h) are permitted. The results of driving resistance measurements on the test track are strongly influenced by the equipment of the test vehicle. Especially the tyres play a major role. It was not possible to carry out any coast-down tests as part of the program. The influence of driving resistance was therefore investigated by making maximum use of the permissible tolerances and reducing the load setting of the dynamometer by 20 % at 20 km/h and by 10 % in the upper speed range of 40 km/h to 120 km/h compared with the type approval setting. Figure 3.1 shows the driving resistance value for type approval determined on the test track, the dynamometer setting for the basic test and the reduced load setting as an example for one test vehicle. Driving Resistance Power [kw] Speed [km/h] Driving Resistance Dynamometer Setting Reduced Load Figure 3.1: Driving resistance, dynamometer setting and reduced load

10 Influence of the driver: The New European Driving Cycle (NEDC), as amended by Directive 98/69/EC, defines certain tolerances on the driving curve. The deviation from the target curve must not exceed ±2 km/h or ±1.0 seconds. CO 2 emissions can be improved if specially trained drivers make full use of these tolerances. Manufacturers are allowed to use their own drivers and dynamometers The drivers can be trained in the special features of the test vehicles and can follow instructions given by the development department. To evaluate the impact of the driver's influence, attempts were made to make the maximum possible use of the permitted tolerances on the driving curve. Conditioning: Before starting the measurement over the NEDC the test vehicle has to be parked at ambient temperatures for six hours to simulate a cold start. Before the measurements are started, the deviation between the oil temperature and the temperature of the room must be no more than 2 C. For CO 2 emission measurements, the test vehicle can be conditioned to a temperature between 20 C and 30 C. If the upper limit is used, the higher oil temperature can minimize the friction loss during cold starts. If maximum use is made of the permitted tolerances, lower fuel consumption can therefore be expected. The influence of the soak temperature was investigated by placing the vehicle in a soak room with an ambient temperature of 28 C for at least 6 hours. The oil temperature at the start of the measurements was between 28 C and 30 C. Optimized measurement (best case) In order to assess the leeway allowed by current type approval testing regulations, all the optimization measures described above were combined for these measurements. The same inertia mass as during type approval testing was used. The driving resistance was reduced, the permitted tolerances on the driving curve were utilized and the vehicles were conditioned at an ambient temperature of 28 C for at least six hours before the tests were started. In addition, investigations were made of certain parameters which are currently of no importance for type approval but may possibly provide new information for future regulations. Gear shift points: In the case of vehicles with automatic transmissions and hybrid vehicles equipped with a gear shift indicator, the manufacturer is allowed to determine the gear shift points to be used in the NEDC. In contrast, the gear shift points for vehicles with manual transmissions are laid down in the Directive although the driving curve with gear shift points and the engine speed/road speed relationship are not always in line with the characteristics of the vehicle. Utilizing gear shift indicators (GSI) and the elimination of the shift points from the driving curve would be one possibility of adapting the driving curve to the state of the art.

11 Start-stop system: The number of modern vehicles with automatic start-stop system is steadily growing. With a system of this type the engine is stopped automatically when the vehicle comes to a standstill and the clutch is disengaged; when the clutch is re-engaged, the engine is automatically started. The objective of a start-stop system is to reduce fuel consumption and emissions. In order to assess the influence of an automatic start-stop system, measurements were made with the system activated and de-activated. State of charge (SOC) of the battery: Ancillary systems such as air conditioning systems, heaters, power-assisted steering pumps etc. remain deactivated for type approval testing. It is therefore difficult to assess actual fuel consumption because the manufacturer only indicates that additional equipment may lead to higher fuel consumption. Another factor which affects the results is the state of charge (SOC) of the battery which is subject to deterioration over the battery lifetime. In many cases, the battery is charged during conditioning prior to type approval testing to ensure that the vehicle needs to generate as little electric power as possible during the tests. To assess the influence of additional electrical equipment and the deterioration of battery charge, measurements were made with a battery discharged to a level where the battery had to be charged during the CO 2 measurement and higher energy output was required from the internal combustion engine. The objective of the investigation is to evaluate the influence of different parameters on the measurement of CO 2 emissions and fuel consumption during type approval testing. Proposals for the future development of the directive concerning CO 2 emissions testing of as part of type approval testing were made on the basis of the test results.

12 Selection of Test Vehicles The objective of the investigation is to evaluate the influence of different parameters on the measurement of CO 2 emissions and fuel consumption during type approval testing. The investigations therefore concentrated on the influence of the various parameters rather than on an assessment of the vehicles selected. In order to investigate the range of effects of the various parameters, different vehicle designs were considered. The choice of vehicles was based on a number of different criteria. State-of-the-art vehicles were selected for the investigations and vehicles equipped with spark-ignition and compression-ignition engines were considered. The selection of the test vehicles was based on the vehicle registration statistics of KBA (the German Federal Office for Motor Traffic). /7/, /8/, /12/ New passenger car registrations in Germany 4,0 Registrations [million ] 3,5 3,0 2,5 2,0 1,5 1,0 0,5 0,0 All Diesel Figure 3.2: New passenger car registrations in Germany from 1990 to 2008, Source: KBA Figure 3.2 shows the percentage of diesel vehicles in newly registered in Germany from 1990 to In 2009 the proportion of diesel vehicles dropped to 30.7 % as a result of the German car scrappage incentive, which led to an increase in sales of smaller and less expensive vehicles. In the first few months of 2010, the share of diesel stabilized at approx. 40 %. For this programme, it was decided that 50 % of the test vehicles should be powered by diesel engines. /9/, /10/

13 Different displacement classes were taken into account. The investigation was also intended to cover vehicles produced by different manufacturers. The objective was to choose representative test vehicles. Figure 3.3 shows the percentage share of different car manufacturers in new vehicle registrations in the Federal Republic of Germany in New passenger car registrations in Germany, 2009 Others; 20.92% AUDI; 7.60% BMW; 8.35% CITROEN; 3.28% FIAT; 5.31% FORD; 9.41% VOLKSWAGEN; 26.06% MERCEDES; 9.14% TOYOTA; 4.48% SKODA; 6.17% RENAULT, DACIA; 7.31% OPEL; 10.96% PEUGEOT; 4.21% Figure 3.3: New passenger car registrations in Germany 2009, source: KBA Table 3.1 shows the data of the test vehicles selected. The test vehicles were hired for the investigation period. No. Manufacturer Type Engine Displacement Power output Approval 1 VOLKSWAGEN Golf Petrol 1,390 cm 3 90 kw Euro 5 2 OPEL Corsa Petrol 1,229 cm 3 59 kw Euro 4 3 BMW 320i Petrol 1,995 cm kw Euro 5 4 PEUGEOT 207HDI Diesel 1,560 cm 3 66 kw Euro 4 5 AUDI A4 TDI Diesel 1,968 cm kw Euro 5 6 DAIMLER C200 CDI Diesel 2,143 cm kw Euro 5 Table 3.1: Test vehicles selected

14 After the vehicles had been delivered, checks were made to ensure compliance with the specified servicing intervals (using the service manuals) and to ensure that the vehicles were in proper condition. Before tests on the dynamometer were started, the on-board diagnosis systems were read out. No errors were stored in the diagnosis system memories of any of the vehicles. 3.3 Performance of the Investigations The type approval testing cycle, the New European Driving Cycle, as amended by Directive 98/69/EC, was used for the investigations. The NEDC consists of two sections (Figure 3.4). At first the test vehicle is conditioned to ambient temperatures between 20 and 30 C for at least six hours. The actual driving cycle begins with a cold engine start. In accordance with Directive 98/69/EC, sampling starts immediately after the engine is started, followed by the EC urban cycle (780 sec) and the extra-urban driving cycle (400 sec). The emission values measured during the two sections are combined to form a single result. The distance driven is about 11 km, at an average speed of 33.6 km/h and a maximum speed of 120 km/h Urban driving cycle Extra-urban driving cycle Speed [km/h] Time [s] Figure 3.4: Speed-time-gradient of the NEDC During the measurements on the dynamometer, the emissions of carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO X ) und carbon dioxide (CO 2 ) are recorded (modal measurement). The fuel consumption is calculated from the emissions of exhaust gas components containing carbon (CO 2, CO und HC) in accordance with Amendment Directive 1999/100/EC and Regulation (EC) No. 715/2007. Table 3.2 summarizes the basic conditions for the individual measurements.

15 Measurement Manufacturer's declared value Basic test Increased inertia mass (worst case) Variation of load Influence of the driver Conditioning at 28 C Optimized measurement (best case) Variation of gear shifting Deactivation of the start-stop system Low battery Basic conditions Manufacturer's declared value for CO 2 emissions and fuel consumption based on the results of type approval testing Inertia mass in accordance with type approval testing Driving resistance in accordance with type approval testing Driving curve followed exactly Conditioned to 22 C Gear shifts in accordance with directive (or as defined by manufacturer for DSG) Start-stop system activated Battery fully charged Increase in the inertia mass by two classes to take account of additional equipment All other parameters as for the basic test Reduction in load of 20% at 20 km/h and 10% at 40 km/h to 120 km/h All other parameters as for the basic test Utilization of the tolerances of the driving curve, All other parameters as for the basic test Conditioning of the vehicle at 28 C over at least 6 hours before testing, All other parameters as for the basic test Inertia mass in accordance with type approval testing Reduction in load of 20% at 20 km/h and 10% at 40 km/h to 120 km/h Utilization of the tolerances of the driving curve Conditioning of the vehicle at 28 C Gear shifts in accordance with directive (or as defined by manufacturer for DSG) Start-stop system activated Battery fully charged Optimization of the gear shift points using manual gearboxes, or using the manual shift curve for DSG, All other parameters as for the basic test Deactivation of the start-stop system, All other parameters as for the basic test Discharging of the battery before testing to a level at which the battery needs to be charged, All other parameters as for the basic test Table 3.2: Basic conditions for the measurements

16 To allow well-founded statistical evaluations, at least three measurements were made both for the determination of the initial condition and for each individual parameter. The performance of the measurements and the basic conditions applicable to each of the measurements are explained in detail in Section 3.1. In the course of work on the project, the test programme was expanded by agreement with the Federal Environment Agency on the basis of the results obtained with the first two test vehicles. In addition, different factors were considered in some cases in view of the different equipment levels of the test vehicles. The test programme is summarized in Table 3.3. Measurement Test vehicle Basic measurement X X X X X X Increased inertia mass X X X X X Reduced load X X X X X Influence of the driver X X X X X X Conditioning to 28 C X X X X X X Optimized measurement X X X X Variation of gear shifting X X X X X X Start-stop system off X X Low battery X X X X Table 3.3: Test programme The investigation programmes for the individual vehicles and the results of the measurements are presented in Section 4.

17 Test Results 4.1 Test Vehicle VW GOLF 1.4 TSI The technical data of the VW GOLF VI test vehicle were as follows: Manufacturer: Vehicle type: Model name: VOLKSWAGEN 1K Golf VI Emission class: Euro 5 Mileage: Engine model: Engine type: Engine power output: Gearbox: Tyre size: Inertia mass: 13,921 km CAX (1.4 l TSI) Petrol (direct injection / turbocharged) 90 kw / 5000 rpm dual-clutch transmission, 7-speed (DSG-7) 225/45R17 91W 1470 kg The following tests were carried out on this test vehicle: Basic measurement Influence of the driver, utilizing the tolerances of the driving curve Conditioning to 28 C ambient temperature Variation of gear shifting (DSG, shifted manually) The VW Golf test vehicle was equipped with a DSG dual-clutch transmission that combines the benefits of an automatic transmission and a manual gearbox. This means that the vehicle could be driven both using the automatic driving curve and using the driving curve for manual gearboxes. All the measurements were made in the automatic mode, as for the type approval tests, except that the "variation of gear shifting" tests were carried out using the manual shift mode with the appropriate driving curve. The test results for the VW Golf are shown in Table 4.1.

18 Measurement Results Deviation from basic measurement CO 2 emissions [g/km] FC [l/100km] CO 2 emissions [%] FC [%] UDC EUDC NEDC NEDC UDC EUDC NEDC NEDC Manufacturers' values Basic measurement Influence of driver Conditioning to 28 C DSG in manual mode Table 4.1: Test results for VW Golf The absolute test results and the relative deviations from the basic measurement results are shown in Figures 4.1 and manufacturer's declared values basic measurement 220 DSG shifted manual oil and water temperature 28 C optimized driving CO [g/km] UDC EUDC Combined Figure 4.1: Overview of the CO 2 results with variation of different parameters for the VW Golf test vehicle

19 manufacturer's declared values DSG shifted manually oil and water temperature min. 28 C optimized driving % UDC EUDC -0.5 Combined Figure 4.2: Relative deviation of the CO 2 emissions from the basic measurement results with variation of different parameters for the VW Golf test vehicle The lowest CO 2 emissions obtained for the VW Golf were the values declared by the manufacturer for type approval. The highest values were determined when the DSG gearbox was shifted manually. In contrast, it was not found that the influence of the driver or higher conditioning temperature had any significant impact.

20 Test Vehicle OPEL CORSA 1.2 L The technical data of the OPEL CORSA 1.2 L test vehicle were as follows: Manufacturer: Vehicle type: Model name: OPEL S-D OPEL CORSA Emission class: Euro 4 Mileage: Engine model: Engine type: Engine power output: Gearbox: Tyre size: Inertia mass: 20,927 km Z12XEP (1.2l) Petrol (Multipoint-Inlet Manifold-Injection) 59 kw / 5600 rpm Manual gearbox, 5-speed (MT5) 185/65R15 88T 1130 kg The following tests were carried out on this test vehicle: Basic measurement Variation of the inertia mass (worst case) Variation of driving resistance on the dynamometer Influence of the driver, utilizing the tolerances of the driving curve Conditioning to 28 C ambient temperature Variation of gear shifting The test results for the OPEL CORSA are shown in table 4.2. The absolute test results and the relative deviations from the basic measurement results are shown in Figures 4.3 and 4.4.

21 Measurement Results Deviation from basic measurement CO 2 emissions [g/km] FC [l/100km] CO 2 emissions [%] FC [%] UDC EUDC NEDC NEDC UDC EUDC NEDC NEDC Manufacturer s values Basic measurement Increased inertia mass Reduced load Influence of the driver Conditioning to 28 C Variation of gear shifting Table 4.2: Test results for OPEL CORSA manufacturer's declared values basic measurement driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast down curve CO2 [g/km] ,8 optimized gear shifting inertia mass high (2 steps) UDC EUDC Combined Figure 4.3: Overview of the CO 2 results with variation of different parameters for the OPEL CORSA test vehicle

22 UDC EUDC Combined , , % manufacturer's declared values driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast down curve (low load) optimized gear shifting inertia mass high (2 steps) Figure 4.4: Relative deviation of the CO 2 emissions from the basic measurement results with variation of different parameters for the OPEL CORSA test vehicle The lowest CO 2 emissions obtained for the OPEL CORSA were measured during the tests with optimized gear shifting. The highest values were measured during tests with the inertia mass increased by 2 classes, which can be considered as the worst case scenario with reference to the current type approval testing conditions. A significant reduction in CO 2 emissions was also observed during the tests with reduced load and increased conditioning temperature.

23 Test Vehicle BMW 320i The technical data of the BMW 320i test vehicle were as follows: Manufacturer: Vehicle type: Model name: BMW 390L BMW 320i Emission class: Euro 5 Mileage: 17,527 km Engine model: N43D20A (2.0 l) Engine type: Engine power output: Gearbox: Tyre size: Inertia mass: Special feature: Petrol (direct injection) 125 kw / 6700 rpm manual gearbox, 6-speed (MT-6) 205/55R16 91H 1470 kg start-stop system The following tests were carried out on this test vehicle: Basic measurement Variation of the inertia mass (worst case) Variation of driving resistance on the dynamometer Influence of the driver, utilizing the tolerances of the driving curve Conditioning to 28 C ambient temperature Optimized measurement (best case: combination of low inertia mass, utilization of the tolerances for adapting the driving resistance curve, increasing the water and oil temperature to 28 C and optimized driving inside the tolerance range of the NEDC) Deactivation of the start-stop function Variation of gear shifting Partially discharged starter battery ( low battery ) The test results for the BMW 320i are shown in Table 4.3.

24 Measurement Results Deviation from basic measurement CO 2 emissions [g/km] FC [l/100km] CO 2 emissions [%] FC [%] UDC EUDC NEDC NEDC UDC EUDC NEDC NEDC Manufacturer's values Basic measurement Increased inertia mass Reduced load Influence of the driver Conditioning to 28 C Best case Variation of gear shifting Without start/stop system Low battery Table 4.3: Test results for BMW 320i The lowest CO 2 emissions for the BMW 320i test vehicle were measured during the test with optimized gear shifting. The highest values were measured with the battery partially discharged before testing. A significant reduction in CO 2 emissions compared with the basic measurement was obtained by reducing the load setting, adopting optimized driving behaviour and conditioning to 28 C. The absolute test results and the relative deviations from the basic measurement results are shown in Figures 4.5 and 4.6.

25 CO2 [g/km] , manufacturer's declared values basic measurement driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast down curve optimized gear shifting inertia mass high (2 steps) start/stop deactivated best case low battery , ,7 175, UDC EUDC Combined Figure 4.5: Overview of the CO 2 results with variation of different parameters for the BMW 320i test vehicle UDC 35.1 manufacturer's declared values driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast down curve (low load) optimized gear shifting inertia mass high (2 steps) start/stop deactivated best case low battery Combined EUDC 8.1 % Figure 4.6: Relative deviation of the CO 2 emissions from the basic measurement results with variation of different parameters for the BMW 320i test vehicle

26 Test Vehicle PEUGEOT 207 HDI The technical data of the PEUGEOT 207 HDI test vehicle were as follows: Manufacturer: Vehicle type: Model name: PEUGEOT WE9HVC Peugeot 207 SW HDI Emission class: Euro 4 Mileage: 9100 km Engine model: 9HV (1.6 l) Engine type: Engine power output: Gearbox: Tyre size: Inertia mass: Diesel (turbocharged / particle filter) 66 kw / 4000 rpm manual gearbox, 5 speed (MT-5) 185/65R15 88H 1250 kg The following tests were carried out on this test vehicle: Basic measurement Variation of the inertia mass (worst case) Variation of driving resistance on the dynamometer Influence of the driver, utilizing the tolerances of the driving curve Conditioning to 28 C ambient temperature Optimized measurement (best case: combination of low inertia mass, utilization of the tolerances for adapting the driving resistance curve, increasing the water and oil temperature to 28 C and optimized driving inside the tolerance range of the NEDC) Variation of gear shifting Partially discharged starter battery ( low battery ) The test results for the PEUGEOT 207 HDI are shown in Table 4.4.

27 Measurement Test results Deviation from basic measurement CO 2 emissions [g/km] FC [l/100km] CO 2 emissions [%] FC [%] UDC EUDC NEDC NEDC UDC EUDC NEDC NEDC Manufacturer's values Basic measurement Increased inertia mass Reduced load Influence of the driver Conditioning to 28 C Best case Variation of gear shifting Low battery Table 4.4: Test results for PEUGEOT 207 HDI The lowest CO 2 emissions for the PEUGEOT 207 HDI test vehicle were obtained by using optimized gear shifting. The highest values were determined with the battery partially discharged before testing. Reduced load and conditioning to 28 C led to significantly lower carbon dioxide emissions. In contrast an increase in CO 2 emissions was, as expected, determined with an increase of two classes in the inertia mass. The absolute test results and the relative deviations from the basic measurement results are shown in Figures 4.7 and 4.8.

28 CO2 [g/km] , manufacturer's declared values basic measurement driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast down curve optimized gear shifting inertia mass high (2 steps) best case low battery , UDC EUDC Combined Figure 4.7: Overview of the CO 2 results with variation of different parameters for the PEUGEOT 207 HDI test vehicle UDC 14.9 manufacturer's declared values driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast down curve (low load) optimized gear shifting inertia mass high (2 steps) best case low battery 8.6 EUDC Combined % Figure 4.8: Relative deviation of the CO 2 emissions from the basic measurement results with variation of different parameters for the PEUGEOT 207 HDI test vehicle

29 Test Vehicle AUDI A4 AVANT TDI The technical data of the AUDI A4 TDI test vehicle were as follows: Manufacturer: Vehicle type: Model name: AUDI B8 AUDI A4 AVANT TDI Emission class: Euro 5 Mileage: Engine model: Engine type: Engine power output: Gearbox: Tyre size: Inertia mass: Special feature: 2,540 km CAGA (2.0l) Diesel (direct injection/turbocharged) 105 kw / 4200 rpm manual gearbox, 6-speed (MT-6) 245/40R18 93Y 1590 kg start-stop system The following tests were carried out on this test vehicle: Basic measurement Variation of the inertia mass (worst case) Variation of driving resistance on the dynamometer Influence of the driver, utilizing the tolerances of the driving curve Conditioning to 28 C ambient temperature Optimized measurement (best case: combination of low inertia mass, utilization of the tolerances for adapting the driving resistance curve, increasing the water and oil temperature to 28 C and optimized driving inside the tolerance range of the NEDC) Variation of gear shifting Deactivation of the start-stop function Partially discharged starter battery ( low battery ) The test results for the AUDI A4 AVANT TDI are shown in Table 4.5.

30 Measurement Test results Deviation from basic measurement CO 2 emissions [g/km] FC [l/100km] CO 2 emissions [%] FC [%] UDC EUDC NEDC NEDC UDC EUDC NEDC NEDC Manufacturer's values Basic measurement Increased inertia mass Reduced load Influence of the driver Conditioning to 28 C Best case Variation of gear shifting Without start/stop system Low battery Table 4.5: Test results for AUDI A4 AVANT TDI The lowest CO 2 emissions for the AUDI A4 AVANT TDI test vehicle were obtained by optimizing all the variable parameters for type approval testing. A significant reduction in carbon dioxide emissions was also determined with a reduced load setting, increased conditioning temperature and optimized gear shifting. The highest values were measured with the battery partially discharged before testing. The absolute test results and the relative deviations from the basic measurement results are shown in Figures 4.9 and 4.10.

31 CO2 [g/km] , manufacturer's declared values basic measurement driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast down curve optimized gear shifting inertia mass high (2 steps) start/stop deactivated best case low battery UDC EUDC Combined Figure 4.9: Overview of the CO 2 emission results with variation of different parameters for the AUDI A4 AVANT TDI test vehicle UDC manufacturer's declared values driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast down curve (low load) optimized gear shifting inertia mass high (2 steps) start/stop deactivated best case low battery Combined 29.5 EUDC 14.0 % , Figure 4.10: Relative deviation of the CO 2 emissions from the basic measurement results with variation of different parameters for the AUDI A4 AVANT TDI test vehicle

32 Test Vehicle DAIMLER C 200 CDI The technical data of the DAIMLER C 200 CDI test vehicle were as follows: Manufacturer: Vehicle type: Model name: DAIMLER 204 K Daimler C200 CDI Emission class: Euro 5 Mileage: 4,800 km Engine model: (2.2 l) Engine type: Engine power output: Gearbox: Diesel (direct injection / turbocharged) 100 kw / 4600 rpm manual gearbox, 6-speed (MT-6) Tyre size: 225/45R17 Inertia mass: 1700 kg The following tests were carried out on this test vehicle: Basic measurement Variation of the inertia mass (worst case) Variation of driving resistance on the dynamometer Influence of the driver, utilizing the tolerances of the driving curve Conditioning to 28 C ambient temperature Optimized measurement (best case: combination of low inertia mass, utilization of the tolerances for adapting the driving resistance curve, increasing the water and oil temperature to 28 C and optimized driving inside the tolerance range of the NEDC) Variation of gear shifting Partly discharged starter battery ( low battery ) The test results for the DAIMLER C 200 CDI are shown in Table 4.6.

33 Measurement Test results Deviation from basic measurement CO 2 emissions [g/km] FC [l/100km] CO 2 emissions [%] FC [%] UDC EUDC NEDC NEDC UDC EUDC NEDC NEDC Manufacturer's values Basic measurement Increased inertia mass Reduced load Influence of the driver Conditioning to 28 C Best case Variation of gear shifting Low battery Table 4.6: Test results for DAIMLER C 200 CDI The lowest CO 2 emissions for the DAIMLER C 200 CDI test vehicle were obtained by optimizing all the variable parameters for type approval testing. The highest values were measured with the battery partially discharged before testing. A significant reduction in carbon dioxide emissions was also determined with a reduced load setting and optimized gear shifting. The absolute test results and the relative deviations from the basic measurement results are shown in Figures 4.11 and 4.12.

34 CO2 [g/km] , manufacturer's declared values basic measurement driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast-down curve optimized gear shifting inertia mass high (2 steps) best case low battery 129, UDC EUDC Combined Figure 4.11: Overview of the CO 2 emission results with variation of different parameters for the DAIMLER C 200 CDI test vehicle UDC 30.8 manufacturer's declared values driving curve optimized oil and water temperature min. 28 C tolerance adaptation coast-down curve (low load) optimized gear shifting inertia mass high (2 steps) best case low battery EUDC Gesamt % Figure 4.12: Relative deviation of the CO 2 emissions from the basic measurement results with variation of different parameters for the DAIMLER C 200 CDI test vehicle

35 Evaluation 5.1 Parameters affecting CO 2 measurements Table 5.1 provides an overview of the deviations of the CO 2 emissions from the results of the basic measurement determined by varying the different parameters for the individual test vehicles. The results of the urban driving cycle (UDC), the extra-urban driving cycle (EUDC) and the entire New European Driving Cycle (NEDC) are shown separately. The effects of the individual parameters on the results of the CO 2 measurements are presented and explained in the following paragraphs.

36 Measurement Deviation of the CO 2 emissions from the basic measurement [%] Petrol vehicles Diesel vehicles UDC EUDC NEDC UDC EUDC NEDC UDC EUDC NEDC UDC EUDC NEDC UDC EUDC NEDC UDC EUDC NEDC Manufacturer's declared values Increased inertia mass Reduced load Influence of the driver Conditioning to 28 C Optimized measurement Variation of gear shifting Start-stop system deactivated Low battery * 11.2 * 17.4 * *) explanation see chapter 4.1 Table 5.1: Effect of the parameters on CO 2 emissions over the NEDC for the different test vehicles

37 Basic Measurement In Figure 5.1, the carbon dioxide emissions determined in the basic measurements are compared with the values declared by the manufacturers Petrol vehicle Diesel vehicle CO2 emissions [g/km] Vehicle Values declared by manufacturer Basic measurement Figure 5.1: Comparison of CO 2 emissions determined by basic measurement with values declared by the manufacturers The graph clearly shows that the values determined by the basic measurement were higher than those declared by the manufacturers for all the test vehicles, even though the same inertia mass and load settings were used as for the type approval tests. In this context, it should be noted that the CO 2 emissions and fuel consumption values declared by the manufacturer are allowed to deviate about 4 percent from the results of type approval testing. In the case of vehicles 2 (OPEL CORSA) and 4 (PEUGEOT 207HDI), the results of the basic measurements are within the permitted tolerance range. For vehicle 1 (VW GOLF) the air conditioning compressor could not be deactivated completely as in the type approval procedure, but was driven with zero output by a swash plate. It was also not possible to switch off the daytime running lights of the Golf for testing. The additional energy consumption of the air conditioning compressor and the lights may have caused the increase in CO 2 emissions compared with the manufacturer's declared values. In the case of vehicles 5 (AUDI A4 TDI) and 6 (MERCEDES C200 CDI) the CO 2 emissions determined by the basic measurements were more than 10 % in excess of