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Volkswagen Polo Bluemotion CLEAN DIESEL

Test results report

May 2010

2

Disclaimer Notice Transport Canada’s ecoTECHNOLOGY for Vehicles program (“eTV”) tests emerging vehicle technologies to assess their performance in accordance with established Canadian motor vehicle standards. The test plan presented herein does not, in itself, represent an official determination by Transport Canada regarding fuel consumption or compliance with safety and emission standards of any motor vehicle or motor vehicle component. Transport Canada does not certify, approve or endorse any motor vehicle product. Technologies selected for evaluation, and test results, are not intended to convey policy or recommendations on behalf of Transport Canada or the Government of Canada. Transport Canada and more generally the Government of Canada make no representation or warranty of any kind, either express or implied, as to the technologies selected for testing and evaluation by eTV, nor as to their fitness for any particular use. Transport Canada and more generally the Government of Canada do not assume nor accept any liability arising from any use of the information and applications contained or provided on or through these test results. Transport Canada and more generally the Government of Canada do not assume nor accept any liability arising from any use of third party sourced content. Any comments concerning its content should be directed to: Transport Canada Environmental Initiatives (AHEC) ecoTECHNOLOGY for Vehicles (eTV) Program 330 Sparks Street Place de Ville, Tower C Ottawa, Ontario K1A 0N5 E-mail: [email protected] © Her Majesty the Queen in Right of Canada, as represented by the Minister of Transport, 2009-2010

__________________________________________________________________________________ ecoTECHNOLOGY for Vehicles 3

Table of Contents

EXECUTIVE SUMMARY ................................................................................................. 4

1.0 INTRODUCTION.................................................................................................... 7

2.0 TESTING PROGRAM............................................................................................ 7

3.0 TESTING LOCATIONS......................................................................................... 7

4.0 VEHICLE OVERVIEW ......................................................................................... 8

5.0 PHASE I – LABORATORY FUEL CONSUMPTION AND EMISSIONS TESTING.................................................................................................................. 9

5.1 RESULTS ............................................................................................................... 10 5.1.1 2-Cycle Fuel Consumption Results.............................................................. 11 5.1.2 5-Cycle Fuel Consumption Results.............................................................. 12 5.1.3 Emissions Results......................................................................................... 14

6.0 PHASE II – DYNAMIC TESTING...................................................................... 15 6.1 ACCELERATION EVALUATION............................................................................... 16 6.2 MAXIMUM SPEED IN GEAR ................................................................................... 16 6.3 HANDLING ............................................................................................................ 17

6.3.1 Lateral Skid Pad .......................................................................................... 17 6.3.2 Emergency Lane Change Manoeuvre.......................................................... 19

6.4 NOISE EMISSIONS TESTS....................................................................................... 21 6.5 BRAKING............................................................................................................... 24 6.6 SUMMARY REGARDING DYNAMIC TESTING.......................................................... 25

7.0 PHASE III – ON-ROAD EVALUATIONS ......................................................... 25

8.0 CONCLUSION ...................................................................................................... 26

9.0 WHAT DOES THIS MEAN FOR CANADIANS............................................... 27


EXECUTIVE SUMMARY Diesel vehicles have come a long way over the past few years. As a result of several technological innovations, modern diesel vehicles are cleaner, less noisy and more efficient than previous generations. Advanced clean diesel vehicles continue to be very cost effective to operate. They can be up to 30% more efficient than traditional gasoline engines, resulting in lower greenhouse gas emissions and reduced fuel consumption in certain applications. The Volkswagen Polo is a sub-compact passenger vehicle that was designed and built to conform to European specifications. It is powered by a diesel engine with a 1.4-litre inline 3-cylinder turbocharged engine. Winner of the World Green Car of the Year Award in 2008 and 2010, the Polo was included in the eTV fleet of test vehicles because it incorporates several fuel-conserving and advanced technologies such as direct injection, exhaust gas recirculation, a catalytic coated diesel particulate filter and variable geometry turbine turbocharging. The Polo was tested and evaluated over three phases: laboratory fuel consumption and exhaust emissions; dynamic track testing; and on-road evaluations. The following is a summary of the results obtained from these evaluations.

Criteria Results

Fuel consumption Based on corrected 5-cycle calculations, the Polo’s fuel consumption is 5.9 L/100 km in the city, 4.2 L/100 km on the highway and 5.1 L/100 km combined. These fuel consumption rates are in keeping with the actual fuel consumption achieved over the first 5,000 kilometres of operation. Based on an average of 20,000 km of driving per year and fuel costs of $1.00/L, fuel cost for the Polo would be approximately $1,020 per year.

CO2 emissions In combined city and highway tests, the Polo’s emissions value is 109 g/km. This is 29% lower than the two most fuel-efficient sub-compacts currently available in Canada. The Polo leaves a low carbon footprint of 2,700 kg of CO2 emissions per year emitted from the tailpipe (based on 20,000 km driven annually).

Exhaust Emissions The 2008 VW Polo was designed to meet the Euro IV emissions standards. As is typical of all well-functioning diesel-powered vehicles, the carbon monoxide and hydrocarbon emissions values were well below Canadian standards. However, it would need to improve its particulate matter (PM) and nitrogen oxide (NOx) emissions values in order to meet both Euro V and the average North American emissions standards for a light-duty vehicle (Tier 2, Bin 5). Polo (actual results): PM 0.019 g/mile NOx 0.41 g/mile


Criteria Results

Euro IV standard: PM 0.040 g/mile NOx 0.40 g/mile Canadian limit: PM 0.010 g/mile NOx 0.05 g/mile

Dynamic Performance

Overall, handling and performance were either good, pass or acceptable relative to the sub-compact class. As such, dynamic performance would not pose a barrier to its inclusion in the fleet of sub-compact vehicles in Canada. Maximum speed and maximum speed in gear are rated as acceptable to

good. The maximum lateral acceleration is 9.1 m/s2 and 61 km/h for a 61 m

turning circle. Emergency lane change performance is rated as good. External and internal noise levels were well below the limits set out in

the CMVSS. Braking is compliant with all aspects of the CMVSS 135 standard.

Evaluations Common driver evaluation comments included good low-end torque (allowing for quick acceleration from a stopped start), good interior space, including headroom, and reasonable cargo space for a sub-compact vehicle. Drivers also commented on the amount of vibration produced by the diesel engine and how it was significantly more noticeable than in a gasoline engine, especially when idling.

Barriers to the Introduction of Advanced Diesel Technologies into the Canadian Market There are two principle market barriers to the introduction of the latest generation of clean diesel vehicles into the Canadian market, including: consumer misperceptions regarding diesel vehicles; exhaust emission limits with which manufacturers must comply. Consumer Barriers The consumer adoption of diesel vehicle technologies in Canada, and North America more generally, has been low due to a number of barriers, including historical concerns about vehicle reliability, diesel fuel costs, and concerns about noise, vibrations and emissions. 1 Market research suggests that legacy performance concerns, which occurred in the 1970s and 1980s, continue to discourage consumer uptake of diesels today, despite the significant

1 Kurani, Kenneth S. and Daniel Sperling (1988). Rise and Fall of Diesel Cars: A Consumer Choice Analysis. Transportation Research Record (1175), 23 – 32.


technical progress that has been made in addressing these issues.2 In reality, the latest generation of clean diesel technologies, such as those found in the VW Polo Bluemotion TDI, has helped improve the fuel efficiency of diesel vehicles, while reducing vibration and emissions. Despite these technological improvements, the rate of diesel vehicle adoption in Canada has remained low because Canadian consumers have maintained these historical perceptions. One of eTV’s objectives in testing the VW Polo is to help change consumer perceptions by presenting results that demonstrate the real-world performance benefits of clean diesel vehicles in Canada – results that directly challenge these perceptions. Regulatory Barriers North American and European exhaust emission and crash test standards differ in several areas. As a result, many European vehicle models, such as the VW Polo, cannot be approved for the Canadian market without performing additional compliance testing and/or vehicle modifications. While vehicle manufacturers are responsible for choosing the suite of vehicles and technologies they introduce in Canada, eTV works in partnership with industry to facilitate the introduction of these new technologies by helping increase market demand through consumer outreach, and by undertaking testing to demonstrate the potential of these new technologies.

2 Kliesch, J. and T. Langer (2003). Deliberating Diesel: Environmental, Technical and Social Factors Affecting Diesel Passneger Vehilce Prospects in the United States. American Council for a Fuel Efficient Economy.


1.0 INTRODUCTION Diesel vehicles have come a long way over the past few years. As a result of several technological innovations, modern diesel vehicles are cleaner, less noisy and more efficient than previous generations. Advanced clean diesel vehicles continue to be very cost effective to operate. They can be up to 30% more efficient than traditional gasoline engines, resulting in lower greenhouse gas emissions and reduced fuel consumption in certain applications. Modern diesels are equipped with a variety of advanced technologies that reduce harmful by-products of combustion, including particulate matter and nitrogen oxides. For example, innovations include exhaust gas recirculation, diesel particulate filters, common rail direct injection, selective catalytic reduction and diesel exhaust fluid. Working in partnership with Volkswagen AG headquartered in Wolfsburg, Germany and with Volkswagen Canada, the eTV program selected the Polo Bluemotion TDI for testing because it is equipped with several technologies to reduce fuel consumption – technologies such as variable geometry turbocharging (VGT), exhaust gas recirculation (EGR), advanced aerodynamics, low rolling resistance tires and a diesel particulate filter. The Polo also captured eTV’s attention when it was awarded the World Green Car of the Year award in 2008, an exploit it repeated in 2010. 2.0 TESTING PROGRAM The Polo was tested and evaluated over three distinct phases: laboratory fuel consumption and exhaust emissions; dynamic track testing; and on-road evaluations. Together, these various phases were designed to realistically assess the vehicle’s overall performance and identify any possible barriers that may negatively impact the introduction of the various advanced technologies featured in the Polo into the Canadian market. The Polo was evaluated using standard testing procedures based on practices used by the Canadian Corporate Average Fuel Consumption (CAFC), the U.S. Environmental Protection Agency, the U.S. Department of Transport, the International Standards Organization and the Society of Automotive Engineers (see VW Polo Bluemotion Test Plan for details). 3.0 TESTING LOCATIONS Phase I testing was performed in partnership with Environment Canada at the Emissions Measurement and Research Division (ERMD) located in Ottawa, Ontario. All fuel consumption and exhaust emissions testing were performed in a controlled laboratory, using a vehicle chassis dynamometer. The laboratory environment ensured that testing was completed to within ± 1 degree Celsius of the required test temperature. Additionally, the vehicle was tested over several separate driving cycles and was maintained to within a ± 1.5 km/h limit of the required speed.


Phase II testing was performed at Transport Canada’s test track facility in Blainville, Québec. The closed test track environment was necessary to ensure that testing was performed in a controlled setting and under controlled conditions. The test track is equipped with over 25 kilometres of road, including both a high-speed and low-speed circuit, to allow for a variety of tests. Phase III comprised on-road evaluations performed by Transport Canada staff as well as by automotive journalists at the program’s public outreach events. In addition, in partnership with the Transport Canada’s Olympic Planning Secretariat, the vehicle was driven by a number of inspectors before and during the 2010 Olympic and Paralympic Winter Games in Vancouver, British Columbia. The inspectors travelled throughout British Columbia, verifying the safety and security of Canada’s transportation system while performing their regular inspection duties. 4.0 VEHICLE OVERVIEW

Figure 1 – Volkswagen Polo Bluemotion TDI The Polo, classified as a sub-compact vehicle, is equipped with a 1.4-litre inline 3-cylinder turbocharged engine. The vehicle’s engine power train is equipped with several environmentally friendly technologies such as exhaust gas recirculation, which helps to reduce nitrogen oxides, a by-product of diesel combustion. As well, the 5-speed manual transmission, with longer gear ratios in gears 3 through 5, provides fuel savings during periods of high speed cruising. The variable turbine geometry turbocharger helps to provide additional power over a longer range of engine speeds. The specifications for the vehicle are presented in the Table 1.


Weight 1,084 kg Drive Type Front-wheel Length 3.92 m Engine In-line 3-cylinder,

turbocharged SOHC Width 1.65 m Transmission 5-speed manual Height 1.47 m Torque 195 Nm / 144 lb-ft @

4,500 rpm Seating 5 Power 59.7 kW / 80 hp @

5,800 rpm Fuel Type Diesel Fuel Efficiency

CityHighway

4.9 L/100 km 3.2 L/100 km

Displacement 1,422 cm3 Fuel Tank Capacity

45 L

Top Speed 176 km/h Driving Range 1,190 km Acceleration 0 to 100 km/h in 12.8

seconds Brakes (f/r) Servo-assisted ventilated

disc/Self-adjusting drum CO2 Emissions 99 g/km Body 3-door hatchback

Table 1: Specifications for the Volkswagen Polo Bluemotion TDI

The vehicle’s aerodynamics have been optimized to include a front fluidic spoiler and a roof spoiler, which results in a low drag coefficient of 0.30. Furthermore, the vehicle is equipped with low rolling resistance tires. Together, these features help the vehicle slip and roll through the air and on the road more easily. 5.0 PHASE I – LABORATORY FUEL CONSUMPTION AND EMISSIONS

TESTING More than 3,500 kilometres of vehicle and engine use were accumulated on the Polo, pursuant to the Code of Federal Regulations (CFR) mileage accumulation procedure3. The procedure outlines the prescribed route that the vehicle must follow, using diesel fuel that is commercially available (<15 ppm of sulphur). Once mileage accumulation was completed fuel consumption and emission tests were performed. Before beginning, the vehicle was soaked4 at a laboratory temperature for no less than 8 hours before each test. This is to ensure that the vehicle may be compared against other test vehicles undergoing the same emissions and fuel consumption evaluations, and that all mechanical components and fluids reach the chosen temperature by the time of testing. Evaluations were then performed over the five duty cycles listed in Table 2.

3 In accordance with 40 CFR 610.51 – Mileage Accumulation Procedure 4 To soak a vehicle means to park it in the test chamber, with the engine turned off, to allow the entire vehicle, including the engine, fluids, transmission and drive train, to reach the test cell temperature prior to the beginning of the test.


Test Parameter Test Standard Number of Tests

(Cell Temperature)

Urban Driving U.S. FTP-75 2 (25°C) Cold Test U.S. FTP-72 1 (-7°C)

Aggressive Driving US06 (SFTP) 1 (25°C) Highway Driving U.S. HWFET 2 (25°C) Electrical Load US SC03 1 (25°C)

Table 2: Chassis Dynamometer Test Schedule The vehicle was mounted on a chassis dynamometer where the front (drive) wheels were allowed to roll against a resistance drum. The drum’s resistance was pre-programmed based on the vehicle’s road load force parameters. Parameters and coefficients were based on a vehicle travelling from a speed of 115 km/h to 15 km/h (71.5 mph to 9.3 mph) while coasting. The final result was a model for road load force as a function of speed, during operation on a dry, level road, under reference conditions of 20°C (68°F) and 98.21 kPa (29.00 in-Hg), with no wind or precipitation and with the transmission in neutral. Environment Canada collected and analyzed exhaust emissions for each of the duty cycles listed in Table 2. The emissions data were analyzed for:

carbon monoxide carbon dioxide total hydrocarbons nitrogen oxides particulate matter

5.1 RESULTS The fuel consumption estimate for the Polo is based on calculations for the 2-cycle city and highway driving cycles and the five-cycle city, highway, cold test, aggressive driving and electrical load driving cycles. The test cycles were developed based on extensive real-world data, such as driving activity, trip length and stopping frequency, among other factors. The 2-cycle value was calculated by adding the results for the urban driving cycle (U.S. FTP-75) and the highway duty cycle (U.S. HWFET), using a ratio of 55% city to 45% highway. The cycles were then adjusted upward 10% and 15% respectively to account for a variety of “real-world” driving factors. The adjustments are meant to account for differences between the way vehicles are driven on the road and over the test cycles. The end result is a combined fuel consumption rating for the vehicle, in addition to separate city and highway results. These are the procedures followed by Natural Resources Canada to determine the values that are published in their annual Canadian Fuel Consumption Guide.


The 5-cycle test method is used to supplement the 2-cycle test method. It takes into account several factors that affect fuel consumption but are not addressed in the current Canadian standard. The U.S. Environmental Protection Agency began to implement 5-cycle testing in 2006. The 5-cycle method includes testing over a wider range of driving patterns and temperature conditions than those tested under the current Canadian standard. For example, in the real world, vehicles are often driven more aggressively and at higher speeds than the existing city and highway test cycles can duplicate. The US06 aggressive driving cycle takes this into account. Furthermore, drivers often use air conditioning in warm and/or humid conditions. In the 2-cycle calculation, this factor is not taken into consideration, since the test does not allow the air conditioning system to be turned on. The US SC03 test cycle reflects the added fuel needed to operate the air conditioning system. As well, given Canada’s climate, a typical vehicle will be driven below 0°C (~ 32°F) on a fairly regular basis. The current 2-cycle testing is only conducted at 25°C (~ 77°F). The U.S. FTP-72 cold test cycle (-7°C) is used to reflect the additional fuel needed to start and operate an engine at lower temperatures. Using the 5-cycle method, therefore, offers a more accurate representation of the vehicle’s fuel consumption and overall performance than the 2-cycle method. Both methods apply adjustment factors to take into account other real-world driving factors such as road grade, wind, low tire pressure and fuel quality. However, because it takes other factors into account, for the same make and model, the 5-cycle method results in fuel consumption values that are approximately 10 to 20% higher than those for the 2-cycle method. 5.1.1 2-Cycle Fuel Consumption Results The Polo was tested twice against the FTP-75 city cycle and the HWFET highway cycle, according to current Canadian standards for fuel consumption testing. The results were averaged for each cycle. Based on the 2-cycle calculations and using the correction factors listed above, the results for the fuel consumption of the Polo are 5.28 L/100km for the city and 3.64 L/100km for the highway. The combined fuel consumption value, using a 55% and 45% weighting for the city and highway respectively, is 4.54 L/100km. Figure 2 below shows the unadjusted combined fuel consumption value of 4.03 L/100km versus the fleet average for model year 2009 as well as the Canadian and US CAFE/CAFC standards. It can be seen that the Polo is more than 50% below the 2009 model year CAFC standard of 8.60 L/100 km and more than 40% below the actual fleet average achieved by all new cars in 2009.


Footprint and L/100 km, CAFE/CAFC

0,0

2,0

4,0

6,0

8,0

10,0

12,0

25,0 30,0 35,0 40,0 45,0 50,0 55,0 60,0 65,0 70,0 75,0

Footprint (square feet)

L/1

00

km

US

Canada

Fleet Average

Target

VW Polo

Figure 2: Unadjusted Fuel Consumption versus Canadian and US Standards

5.1.2 5-Cycle Fuel Consumption Results Each of the 5-cycles is divided into “phases” – also referred to as “bags” because each phase sample is bagged and analyzed separately, without interruption, during the test. The following equations are derived from 40 CRF Parts 86 and 600, to determine both the city and highway fuel economy5 results for a vehicle.

Where: Bag # FE is the fuel economy in US miles per gallon of fuel during the specified bag of the FTP test conducted

at an ambient temperature of 75ºF or 20ºF

5 The term “fuel economy” is used here to reflect the fact that 5-cycle testing is a US standard and not the Canadian standard. In Canada, the terms “fuel consumption” is used.


Under the vehicle-specific 5-cycle formula, the highway fuel economy value is calculated as follows:

The results for the fuel consumption of the Polo, based on the 5-cycle calculations above, are 5.90 L/100km for the city and 4.24 L/100km for the highway. The 5-cycle testing values may provide a more accurate representation of what a user can expect for fuel consumption in real-world driving. When compared against the city and highway values for the 2-cycle calculation, the 5-cycle fuel consumption values are 11% and 16% higher for city and highway driving respectively.


Driving Cycle City Highway Combined 2-cycle 5.28 L/100 km 3.64 L/100 km 4.54 L/100 km 5-cycle 5.90 L/100 km 4.24 L/100 km 5.10 L/100 km

Table 3: Fuel Consumption Results, by Driving Cycle 5.1.3 Emissions Results The results of the city and highway test cycles offer a combined CO2 emissions value of 109 g/km. The two best performing comparable subcompact vehicles for the same model year, currently available on the Canadian market, obtained CO2 emissions value of 152 g/km CO2. Thus technologies such as those being offered in the VW Polo could offer a 29% reduction in CO2 emissions over the current best performers in the sub-compact class. When compared to the national average for all sub-compact cars available in Canada, the CO2 emissions reported for the same model year are 238 g/km. The Polo, therefore, offers a 55% improvement in CO2 emissions over all comparable models. With regard to non-CO2 exhaust emissions, the 2008 Polo was designed to meet the Euro IV emissions standards. In order to meet both Euro V and the average North American emissions standards for a light-duty vehicle (Tier 2, Bin 5), it would need to find a way to lower its particulate matter (soot) and nitrogen oxide (NOx) emissions.

Table 4: Federal Test Procedure - Exhaust Emissions vs. standards (g/mile) Particulate matter (PM) is a common byproduct of the diesel combustion process. Technologies such as diesel particulate filters are designed to limit the amount of particulates that pass through the exhaust stream and into the surrounding atmosphere. The Polo was tested for particulate matter on the FTP-75 test cycle. The average PM value was 0.019 g/mi. As such, the Polo is below the Euro IV PM emissions standards of 0.040 g/mi but exceeds the current Canadian limit of 0.010 g/mi. Nitrogen oxides (NOx) contribute to ground level smog concentrations that can result in respiratory ailments. The Polo very nearly meets the Euro IV limit for NOx, but exceeds the Canadian standard of 0.05 g/mi by a significant margin. Anti-NOx technologies such as selective catalytic reduction would likely need to be included in order to conform to both Euro V and Canadian NOx emissions standards. As is typical of all well functioning diesel powered vehicles, the carbon monoxide and hydrocarbon emission values were well below Canadian standards.

CO NMHC HCHO PM NOx

VW Polo 0.16 0.012 0.003 0.019 0.41

Standard – Tier 2, Bin 5 3.40 0.075 0.015 0.010 0.05

Euro 4 – Diesel standard 0.80 - - 0.040 0.40


Emissions as well as fuel consumption standards are met on a manufacturer’s sales weighted average. Individual models may exceed these standards as long as the manufacturer’s fleet as a whole is in compliance. It is assumed that should volkswagen choose to offer the Polo in the Canadian market, the vehicle would need to be modified to meet the average Canadian standard for both PM and NOx. 6.0 PHASE II – DYNAMIC TESTING The Polo underwent dynamic and performance testing in June and July 2009. Most aspects of the tests performed were for general dynamic assessment purposes only and not as a measure of compliance with the Canada Motor Vehicle Safety Standards (CMVSS). Concerns about fuel-efficient vehicles are not always limited to exhaust emissions and greenhouse gas reduction. The general dynamic testing was performed because the eTV program wished to assess how well smaller, more fuel-efficient vehicles function in various road situations. Additionally, the eTV program wished to identify any potential issues. As mentioned previously, the dynamic testing was performed at Transport Canada’s test track facility in Blainville, Québec. An aerial view of the test track is provided below. The dynamic test results for the Polo follow.

Figure 3: Aerial View of the Dynamic Test Track, Blainville, Québec


6.1 ACCELERATION EVALUATION The maximum acceleration was determined by starting the vehicle from a standing start and following the procedure set out below. 1. The vehicle was evaluated by accelerating to the maximum attainable speed in a quarter

of a mile (402.3 m). 2. The vehicle was evaluated by accelerating to the maximum attainable speed in a

kilometre (1000 m). Shifting occurred at what was determined to be an optimal shift point. To account for variation in wind, the vehicle was driven in both directions on the test track, with the results averaged.

Distance Speed ( km/hr )

1/4 mile ( 402.33 m) 106.2

1000 m 121.3 Table 5: Average Results for Specified Distances

6.2 MAXIMUM SPEED IN GEAR The maximum speed attainable was tested and recorded for each gear. The driver started from a standing start for first gear only. The vehicle was accelerated, changing gears only when the vehicle engine speed had operated at its maximum peak rpm for at least 3 seconds. The maximum speed and revolutions per minute for each gear was recorded. Since speed is affected by wind, tests were performed in both directions and averaged. Tests took place on July 17, 2009 and the recorded wind speed was 7 km/h. Table 6 lists the maximum speeds obtained in two separate trials in opposite directions for each gear.

Gear selection Vmax (km/h) A. Gear selection no 1 42.7

B. Gear selection no 2 77.5

C. Gear selection no 3 124.3

D. Gear selection no 4 164.4

E. Gear selection no 5 168.2 Table 6: Average Results, Maximum Speed in Each Gear

During testing, the Polo reached a maximum speed of 168.2 km/h in approximately 80 seconds, while operating in 5th gear. Thus, the Polo has the ability to meet and exceed all minimum speed requirements on public roads throughout Canada. Additionally the torque and acceleration compare favourably to typical results in the sub-compact class, and


allow for the highway merging and overtaking that most Canadians have come to expect from their vehicles. The maximum speed and the speed in each gear is shown graphically in one direction before being average, are shown graphically in Figure 4 below.

Maximum Speed in Gear

0

20

40

60

80

100

120

140

160

180

200

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

Time (seconds)

Sp

eed

(km

/h)

2nd

3rd

4th

43.1 km/h

77.5 km/h

123.8 km/h

168.4 km/h

172.2 km/h5th

1st

Figure 4: Maximum Speed in Each Gear, Single Run

6.3 HANDLING

6.3.1 Lateral Skid Pad The lateral skid pad test was used to determine the maximum speed that the Polo could achieve in a cornering situation. When the vehicle reaches its cornering limit, it will either under-steer or over-steer, losing traction on the curve. When the vehicle had almost lost traction, the maximum lateral acceleration was recorded. In order to measure vehicle displacement, speed and lateral acceleration, the Polo was equipped with a combined GPS and accelerometer-based data acquisition system. All measurements refer to the vehicle’s centre of gravity. Tires were warmed up and conditioned by using a sinusoidal steering pattern at a frequency of 1 Hz, a peak steering-wheel angle amplitude corresponding to a peak lateral acceleration


of 0.5–0.6 g, and a speed of 56 km/h. The vehicle was driven through the course four times, performing 10 cycles of sinusoidal steering during each pass. Testing was performed under the following conditions:

The vehicle was equipped with new tires. Tire pressure was adjusted to conform to the manufacturer’s recommendations. The vehicle’s weight was adjusted to its lightly loaded condition. The skid pad was 61 m in diameter.

Figure 5: Test Vehicle on Counter-Clockwise Run

The results presented in Table 7 show that the maximum speed that the vehicle can achieve in a cornering situation is 61 km/h. Higher speeds resulted in a loss of traction (under-steering).

Clockwise Counter-Clockwise Speed (km/h) Stay Inside Corridor? (Yes/No) Speed (km/h) Stay Inside Corridor? (Yes/No)

50 Yes 52 Yes

55 Yes 55 Yes

58 Yes 58 Yes

61 No 62 Yes

60 Yes Table 7: Lateral Skid Pad Test Results

The maximum lateral acceleration is 9.1 m/s2, based on a peak friction coefficient of 98. The coefficient value is dependent on several factors that make it almost impossible to predict the friction forces (magnitude and direction between tires and the test surface). This complex phenomenon depends on a tire longitudinal/lateral motion and will not be discussed here.


As seen in the calculations above, the maximum lateral acceleration recorded on a successful run was 9.1 m/s2. 6.3.2 Emergency Lane Change Manoeuvre The emergency lane change manoeuvre with obstacle avoidance test was performed based on ISO 3888-2:2002 Passenger Cars – Test Track for a severe lane change manoeuvre. During this test, the vehicle entered the course at a particular speed and the throttle was released. The driver then attempted to negotiate the course without striking the pylons. The test speed was progressively increased until instability occurred or the course could not be negotiated.

Figure 6: Emergency Lane Change Course

As illustrated in Figure 6 above, section 4 of the course was shorter than section 2 by one metre in order to get maximum lateral acceleration at this area. Tests were performed in one direction only. If any pylons were hit, the run was disallowed.


Figure 7: VW Polo Emergency Lane Change Course, Disallowed Run

Several tests were necessary to determine at which speed the Polo was able to negotiate all the way through the prescribed course without hitting a pylon. Table 8 lists all runs in increasing order, by speed.

Initial Speed (km/h) Pylon Hit? (Yes/No)

40 No

47 No

54 No

59 No

63 No

63 No

65 Yes

64 Yes

63 No Table 8: VW Polo Emergency Lane Change Results

While there is no pass or fail in terms of speed for emergency lane change manoeuvres, this is a fair assessment of the lateral stability of a vehicle. The maximum successful entry speed through the course was recorded as 63 km/h. This result is fair compared to other vehicles that the eTV program has tested.


-10

-8

-6

-4

-2

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0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Time (seconds)

Lat

eral

Acc

eler

atio

n (

m/s

^2)

Run 54 (km/h): -7.5 (m/s2) Run 63 (km/h): 9.1 (m/s2) Run 64 (km/h): 9.2 (m/s2)

Figure 8: Lateral Accelerations Recorded During Emergency Lane Change Manoeuvres

6.4 NOISE EMISSIONS TESTS

Noise is of concern with diesel vehicles. There is often a complaint with regard to the amount of noise they emit in comparison with gasoline vehicles. The Polo was tested in accordance with the CMVSS 1106 Noise Emissions Test, SAE Recommended Practice J986, Sound Level for Passenger Cars and Light Trucks and SAE Standard J1470, Measurement of Noise Emitted by Accelerating Highway Vehicles. In order to measure the noise emitted from the engine and exhaust, microphones were set up as shown in Figure 9 below.


Figure 9 : Noise Emissions Setup

Testing was performed under the following conditions: The vehicle test weight, including driver and instrumentation, did not exceed the

vehicle’s curb weight by more than 125 kg; For a period of one minute, the vehicle’s engine speed was returned to idle and the

vehicle’s transmission was set in neutral gear before each run, in order to stabilize the initial transmission and exhaust system temperatures.

The test procedure for the acceleration tests was as follows: When the vehicle approached a speed of 48 km/h ± 1.2 km/h, the speed was stabilized

before the acceleration point; At the acceleration point (± 1.5 m), as rapidly as it was possible to establish, the throttle

was opened wide; Acceleration continued until the entire vehicle had exited the test zone; The sound meter was set to fast dB(A). The deceleration tests followed the same procedure as above, with one modification – at the deceleration point, the vehicle was returned to its idle position until it was equal to one half of the approaching speed or until the entire vehicle had exited the test zone. Results from all tests show that the ambient noise levels are within the limits of the CMVSS 1106 standards. Due to the logarithmic nature of the decibel scale, a level of 61 dB is significantly lower than the 93.8 decibel limit. Generally 60 dB is considered to be the level of normal human conversation while 90 dB would be the sound generated by a typical lawn mower.


The low levels measured for the Polo are a testament to how quiet diesel engines have become as a result of engineering and design improvements and years of refining vehicle design. Most of the noise being generated from the vehicle at these speeds is due to tire and wind resistance, which is acceptable and similar across any vehicle power train platform. Test – side

# Approaching

Speed (km/h)

Approaching RPM

End Speed (1)

(km/h)

RPM max (1)

Noise Level dB (A)

Calibration dB (A)

Right – 1 48 1200 57 1400 61.0 93.8 Right – 2 48 1200 57 1400 61.0 93.8 Right – 3 48 1200 57 1400 61.4 93.8 Right – 4 48 1200 57 1400 61.0 93.8

Average 57 61.1 Left – 1 48 1200 57 1400 61.4 93.8 Left – 2 48 1200 57 1400 61.0 93.8 Left – 3 48 1200 57 1400 61.0 93.8 Left – 4 48 1200 57 1400 60.5 93.8

Average 57 61.0 Results = Highest Average – 2dB 59.1

Ambiant Noise 47.7

Results : Pass

Table 9: External Noise, Approaching 48 km/h Test – side

# Approaching

Speed (km/h)

Approaching RPM

End Speed (1)

(km/h)

RPM max (1)

Noise Level dB (A)

Calibration dB (A)

Right – 1 57 1400 52 1300 60.3 93.8 Right – 2 57 1400 52 1300 60.9 93.8 Right – 3 57 1400 52 1300 60.4 93.8 Right – 4 57 1400 52 1300 60.5 93.8

Average 52 60.5 Left – 1 57 1400 52 1300 60.6 93.8 Left – 2 57 1400 52 1300 60.6 93.8 Left – 3 57 1400 52 1300 60.6 93.8 Left – 4 57 1400 52 1300 60.6 93.8

Average 52 60.8 Results = Highest Average – 2dB 58.8

Ambiant Noise 47.7

Results : Pass

Table 10: External Noise, Approaching 57 km/h Interior noise emitted from the vehicle was evaluated at different constant speeds in order to determine the levels experienced by the driver of the vehicle. It is interesting to note that, except for idling, the Polo experienced a higher dB within the vehicle than the values recorded externally.


Test # and Targeted Test Speed

Calibration dB (A)

Noise Level dB (A)

Transmission Selection

Idle 93.8 48.7 neutral Ambient Temperature 32.2 Engine Off

Full Acceleration – 1 93.8 78.6 25 sec. – 130 km/h – redline Full Acceleration – 2 93.8 77.3 25 sec. – 130 km/h – redline Full acceleration – 3 93.8 78.3 25 sec. – 130 km/h –redline

Average 78.1 25 sec. – 130 km/h –redline 110 km/h – 1 93.8 74.2 5th 110 km/h – 2 93.8 75.3 5th 110 km/h – 3 93.8 74.0 5th

Average 74.5 5th 100 km/h – 1 93.8 74.1 5th 100 km/h – 2 93.8 74.6 5th 100 km/h – 3 93.8 73.2 5th

Average 74.0 5th 80 km/h – 1 93.8 72.1 4th 80 km/h – 2 93.8 71.6 4th 80 km/h – 3 93.8 71.2 4th

Average 71.6 4th 50 km/h – 1 93.8 67.2 3rd 50 km/h – 2 93.8 68.4 3rd 50 km/h – 3 93.8 68.3 3rd

Average 68.0 3rd Table 11: Internal Noise

6.5 BRAKING Testing was performed according to procedures set out in CMVSS 135 - Light Vehicle Brake Systems, with the results set out in Table 12.

Test Description Pass / Fail

Cold Effectiveness Pass High Speed Effectiveness Pass

Stops with Engine Off Pass Failed Antilock Pass

Hydraulic Circuit Failure Pass Power Brake Unit Failure Pass

Parking Brake Pass Hot Performance Pass

Recovery Performance Pass Table 12: Brake Test Results Summary

The Polo is compliant with all aspects of the CMVSS 135 standard. Figure 10 below displays a sample of the stopping distances at two compliance speeds. It should be noted that it is typical for all vehicles to exceed the high-speed braking standard by a greater relative amount than the low-speed braking standard. This is partially due to the difficulty in applying maximum braking pressure at the start of the brake test.


30 m 40 m 50 m 60 m 70 m 80 m 90 m 100 m

70.0 mRegulatedbrakinglimit at 100kph(Dry Conditions)

110 m 120 m

112.76 mRegulatedbrakinglimit at 129kph(Dry Conditions)

74.72 m at high speed(129kph)(Dry Conditions)

44.14 mat 100kph(Dry Conditions)

Figure 10: VW Polo Braking Performance

6.6 SUMMARY REGARDING DYNAMIC TESTING Overall, the dynamic test results show that the Volkswagen Polo Bluemotion TDI meets the relevant Canadians standards. All aspects of handling and performance were either good, pass or acceptable relative to the sub-compact class, and its dynamic performance was similar to that of market competitors in its class. In addition it met all aspects of CMVSS noise and braking standards. 7.0 PHASE III – ON-ROAD EVALUATIONS The eTV engineering team and staff evaluated the Polo’s performance in Ottawa, Ontario and throughout British Columbia. Several departmental safety and dangerous goods inspectors operated the vehicle in the period leading up to and during the 2010 Olympic and Paralympic Winter Games, as they travelled the province verifying the safety and security of Canada’s transportation system and performing their daily inspection duties. Drivers and occupants of the vehicle commented that the Polo was “peppy” and smooth for a 3-cylinder vehicle. Also popular among drivers was the initial torque offered at low rpm, meaning that they were able to accelerate quickly from a stopped start. Of interest was how much interior space was available for a sub-compact vehicle, including the headroom. However, users also commented on the vibration produced by the diesel engine and how it was significantly more noticeable than in a gasoline engine, especially when stopped or idling. Because the Polo is equipped with unit-pump injectors rather than common rail direct injection, this is to be expected. As well, users commented on the need to accelerate higher through gears 4 and 5, as they are very long. This again is expected since the transmission is set up to have longer gear ratios through gears 3, 4 and 5, in order to offer significant fuel savings while cruising. Lastly, the evaluators enjoyed driving with a turbo, some for the first time. They were able to experience firsthand the results of a VTG turbocharger, which contributes to the increased power and the fuel savings that a small, clean diesel engine offers.


Over 5,000 km of evaluations were performed on this vehicle, with an average real-world fuel consumption of 5.1 L/100km (55.4 mpg) being reported. 8.0 CONCLUSION Diesel vehicles have come a long way over the past few years. They are no longer noisy and polluting, and they continue to be very cost effective to operate. Based on an average of 20,000 km of driving per year and fuel costs of $1.00/L, fuel cost for the Polo would be approximately $1,020 per year. As well, the Polo leaves a low carbon footprint of 2,700 kg of CO2 emissions per year emitted from the tailpipe (based on 20,000 km driven annually). In combined city and highway tests, the Polo’s emissions value is 109 g/km. This is 29% lower than the two most fuel-efficient sub-compacts currently available in Canada. With respect to consumer feedback, eTV was able to validate acceptance of several unique technologies, including a transmission optimized to maximize fuel economy and a variable geometry turbocharger (VGTs). Both of these innovations have limited penetration in Canada. Turbochargers have been used by manufacturers to improve engine performance in terms of power. Turbocharging an engine allows manufacturers to reduce overall engine displacement and improve fuel efficiency, while maintaining peak power output. However, traditional turbos often result in moments of lag between the time additional power is demanded through the accelerator and the moment when the turbo spools up enough to provide the extra power. This ‘turbo lag’ sometimes results in a poorer driving experience, and as such, the technology has had limited uptake in Canada since its initial introduction in the 1980s. VGTs, however, have been designed to minimize lag by dynamically controlling airflow across the turbos foils. While this technology has been used in larger displacement engines in heavy duty vehicles for many years, the Polo is the first example of its use in a small displacement diesel engine. eTV’s driver feedback validates the performance of the VGT in eliminating drag, as drivers consistently reported that the vehicle was responsive and able to accelerate quickly from stops. In addition, the vehicle was equipped with a transmission optimized to reduce fuel consumption and emissions. The users experienced this as ‘shorter gears’ at low speeds, requiring more frequent shifting during initial acceleration. Feedback indicated that drivers quickly become accustomed to this configuration, which does not impede vehicle performance. Finally, driver feedback did not include any concerns about particulate matter (or soot), an area where consumers traditionally have concerns about diesel technology. Presumably, the vehicle’s on-board particulate filter and other emissions control technologies, such as exhaust gas recirculation, were able to reduce diesel emissions to levels that drivers felt were comparable to those of gasoline-powered vehicles.


Nevertheless, driver evaluations also indicated that Canadians are still unaccustomed to the higher vibrations and noise of diesel engine technologies, particularly those, like the Polo, which are not equipped with common rail direct injection. It is not clear to what degree this may be a barrier to consumer uptake. 9.0 WHAT DOES THIS MEAN FOR CANADIANS There are two principle market barriers to the introduction of the latest generation of clean diesel vehicles into the Canadian market: consumer barriers and regulatory exhaust emission limits with which manufacturers must comply. Feedback at eTV outreach events confirmed that consumer adoption of diesel vehicle technologies in Canada has been low due to legacy concerns about vehicle reliability, diesel fuel costs and concerns about noise, vibrations and emissions. One of eTV’s objectives in testing the VW Polo is to help change consumer perceptions by presenting results that demonstrate the real-world performance benefits of clean diesel vehicles in Canada – results that directly challenge these perceptions. Driver feedback for the vehicle demonstrated that the technical innovations in clean diesel – variable geometry turbocharging, exhaust gas recirculation, optimized transmissions – have helped address legacy concerns about vehicle pollution, reliability and performance to the point where Canadian market acceptance is likely. However, consumer concerns about noise and vibration have persisted. While the VW Polo passed all pertinent CMVSS noise-level tests, eTV driver evaluations suggest that the manufacturer may need to incorporate additional technologies designed to address this issue, such as common rail direct injection, in order to improve market uptake of clean diesel technologies in Canada. North American and European exhaust emissions standards differ in several areas. As a result, many European vehicle models, such as the VW Polo, cannot be approved for the Canadian market without performing additional compliance testing and/or vehicle modifications. While vehicle manufacturers are responsible for choosing the suite of vehicles and technologies they introduce in Canada, eTV works in partnership with industry to facilitate the introduction of these new technologies by helping increase market demand through consumer outreach, and by undertaking testing to demonstrate the potential of these new technologies.

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