Vehicle emissions of light duty vehicles: carbon, diesels and outlook Ricardo F Martinez-Botas Mechanical Engineering Imperial College London
Contents Progression in vehicle emissions Vehicle emissions test programme VW results NEDC in Dyno RDE & Conformity Factors NEDC in Track Emissions gap NOx CO2 Energy performance of other future vehicles 2
Progression in Vehicle Emissions 3
UK National emissions of air pollutants Department for Environment Food & Rural Affairs
Emission standards g/km number
NOx reductions Euro standards were introduced in 1992 to reduce pollutants from vehicles Successful mechanism for improving air quality. The official Euro 6 NOx limit is over 90% lower than the first Euro standard introduced in 1992. Real-world test data Emissions Testing Programme indicated NOx emissions from the latest Euro 6 diesel cars had been reduced by 44% relative to Euro 5 cars. Meeting NO2 limits close to busy roads continues to be a challenge. In some areas transport is responsible for 80% of roadside NOx on average Evidence of further improvements?
Vehicle Emissions Test Programme October 2015 – April 2016 UK Department for Transport Defeat Device Investigation 7
https://www.gov.uk/government/publications/vehicle-emissions-testing-programme-conclusions UK Department for Transport Defeat Device Investigation 8
https://www.gov.uk/government/publications/vehicle-emissions-testing-programme-conclusions UK Department for Transport Defeat Device Investigation 9
Objectives Revelations in September 2015 that VW Group used software to distort emissions tests Secretary of State informed Parliament of UK’s Vehicle Emissions Test Programme on 10 November 2015, to: Establish whether the use of strategies to defeat emissions tests goes wider than the VW Group Gather much-needed evidence to restore public confidence and improve our understanding of the real world emissions performance of vehicles Official - Sensitive 10 November 16
How vehicles selected Produced list of 100 top selling diesels (based on study of buying preferences 2010-2015) Aimed to capture 75% of sales of top 70 vehicles, representing >50% of all diesels on UK roads All major manufacturers Engine sharing effectively increases the size of our sample Even split of Euro 5 and Euro 6 Snapshot in time of a single example of each model’s NOx performance Official - Sensitive 11 November 16
Methodology – set up Vehicles Vehicles Sourced from car hire fleets Sourced from car hire fleets Unmodified and no defects Unmodified and no defects <30,000 miles <30,000 miles Typical winter grade diesel Typical winter grade diesel Tests Lab: Full lab-grade analysers (plus PEMS to confirm calibration) Track and road: Portable Emissions Measurement Systems (PEMS) Official - Sensitive 12 November 16
Methodology – tests Laboratory 1. Official NEDC test with cold engine at 20-30°C ambient 2. Official NEDC test with fully warmed up engine (repeated) 3. Reversed NEDC test with fully warmed up engine Official - Sensitive 13 November 16
Comparison of NOx emissions on NEDC tests showing impact of VW Group cycle recognition software 250 140 L-NEDC (Hot) L-NEDC Reverse Speed 120 200 100 Emissions (mg/s) Speed (km/h) 150 80 60 100 40 50 20 0 0 0 200 400 600 800 1000 1200 Time (s) Official - Sensitive 14 November 16
Comparison of NOx emissions on NEDC tests showing vehicle which does not appear to vary emissions behaviour 250 140 120 L-NEDC (Hot) L-NEDC Reverse Speed 200 100 Emissions (mg/s) Speed (km/h) 150 80 60 100 40 50 20 0 0 0 200 400 600 800 1000 1200 Time (s) Official - Sensitive 15 November 16
'Cold' versus 'hot' NEDC NOx emissions - lab results 500 Average Laboratory NEDC Cold 450 Average Laboratory NEDC Hot 400 350 NO x emissions (mg/km) 300 250 Euro 5 limit = 180 200 150 Euro 6 limit = 80 100 50 0 Euro 5 Euro 6 Official - Sensitive 16 November 16
Methodology – tests Laboratory 1. Official NEDC test with cold engine at 20-30°C ambient 2. Official NEDC test with fully warmed up engine (repeated) 3. Reversed NEDC test with fully warmed up engine On road Approximation of RDE test (pending confirmation of final requirements) – 1.5 hours on public roads including urban, rural and motorway Official - Sensitive 17 November 16
RDE Testing Undertaken in public roads near VCA. 1.5 hours of continuous driving. PEMS installed. Route included the prescribed: Urban Rural Motorway
19 Real driving NOx emissions - Euro 5 vehicles NOx Emissions (mg/km) 1000 1200 1400 1600 1800 2000 200 400 600 800 0 Official - Sensitive Citroen C4 Ford Mondeo Honda CRV Hyundai i30 Hyundai iX35 Hyundai Santa Fe Kia Sportage Land Rover Freelander Mercedes E250 Nissan Qashqai 1.5 Nissan Qashqai 1.6 Peugeot 208 Range Rover Sport Range Rover Sport Skoda Octavia Vauxhall Astra Vauxhall Corsa Vauxhall Insignia Volvo V40 November 16
20 Real driving NOx emissions - Euro 6 vehicles Official - Sensitive NOx Emissions (mg/km) 1000 1200 1400 1600 1800 2000 200 400 600 800 0 Audi A3 BMW 320d BMW X5 Ford Focus Ford Mondeo Honda CRV Hyundai i30 Jaguar XE Kia Sportage Mazda 6 Mercedes A180 Mini Countryman Peugeot 3008 November 16 Renault Megane Skoda Octavia Toyota Avensis Vauxhall Insignia Vauxhall Mokka VW Golf
NOx Emissions (mg/km) 1000 1200 1400 1600 1800 2000 21 200 400 600 800 Real driving NOx emissions - Euro 5 & 6 vehicles 0 Citroen C4 Official - Sensitive Ford Mondeo Honda CRV Hyundai i30 Hyundai iX35 Hyundai Santa Fe Kia Sportage Land Rover… Mercedes E250 Nissan Qashqai 1.5 Nissan Qashqai 1.6 Peugeot 208 Range Rover Sport Range Rover Sport Skoda Octavia Vauxhall Astra Vauxhall Corsa Vauxhall Insignia Volvo V40 NOx Emissions (mg/km) 1000 1200 1400 1600 1800 2000 200 400 600 800 0 Audi A3 BMW 320d BMW X5 Ford Focus Ford Mondeo Honda CRV Hyundai i30 Jaguar XE Kia Sportage Mazda 6 Mercedes… November 16 Mini… Peugeot 3008 Renault… Skoda… Toyota… Vauxhall… Vauxhall… VW Golf
RDE ambient temperature Temperature warning VW Vauxhall Vauxhall Toyota Skoda Renault Peugeot Mini Mercedes Mazda Tests on the road where performed in Kia Jaguar the winter months Hyundai Honda Ford Variability of results Ford BMW Just what was intended as it was trying BMW Audi to capture a real behaviour Volvo Vauxhall Vauxhall Vauxhall Skoda Range Rover Sport Range Rover Sport Peugeot Nissan Nissan Mercedes Land Rover Kia Hyundai Hyundai Honda Ford Citroen Hyundai 2 4 6 8 10 12 14 16 Degrees C
Conformity Factors Conformity Factors for EURO6 Conformity Factor: CF= RDE NOx/80 15.0 14.0 Based on the RDE results for EURO 6. 13.0 If set at 1.5 none of vehicles would meet 12.0 the requirement. 11.0 10.0 Only three vehicles achieved less than a 9.0 conformity factor less than 2.1(Audi A3, 8.0 Mini Countryman & VW Golf) 7.0 The dialogue with manufacturers 6.0 indicated that the standard would be 5.0 met. 4.0 Average CF=6.2 3.0 2.0 1.0 Audi BMW BMW Ford Ford Honda Jaguar Mazda Mercedes Peugeot Renault Vauxhall Vauxhall VW Hyundai Kia Mini Skoda Toyota
Methodology – tests Laboratory 1. Official NEDC test with cold engine at 20-30°C ambient 2. Official NEDC test with fully warmed up engine (repeated) 3. Reversed NEDC test with fully warmed up engine On road Approximation of RDE test (pending confirmation of final requirements) – 1.5 hours on public roads including urban, rural and motorway Track Replicate official NEDC test plus laboratory variations (as above) plus a further NEDC test with fully warmed up engine but driving speed increased by 10% Official - Sensitive 24 November 16
The NEDC cycle TRACK AT MIRA NEDC
Comparison of 'hot' NEDC in lab and on the track 2400 2200 Average Laboratory NEDC Hot Average Track NEDC Hot 2000 1800 NO x emissions (mg/km) 1600 1400 Euro 5 limit = 180 1200 1000 800 600 Euro 6 limit = 80 400 200 0 Euro 5 Euro 6 Official - Sensitive 26
Track Temperature Temperature warning VW Vauxhall Vauxhall Toyota Skoda Renault Peugeot Mini Mercedes Mazda Kia Jaguar Tests on the road where performed in Hyundai the winter months Honda Ford Ford Variability of results BMW BMW Just what was intended as it was trying Audi Volvo to capture a real behaviour Vauxhall Vauxhall Vauxhall Skoda Range Rover Sport Range Rover Sport Peugeot Nissan Nissan Mercedes Land Rover Kia Hyundai Hyundai Honda Ford Citroen Hyundai 2 4 6 8 10 12 14 16 Temperature C
Track test results Official - Sensitive 28
Dyno vs Track: why such a big difference? What affects the difference between the two What relative Importance* “seemingly identical” test? Aerodynamics: settings of the dyno, commonly know as the coast down values. Flexibility: choosing the most favourable vehicle configuration. Test temperature : particularly in relation to EGR regulation regime. Weight: difference between vehicles. Cornering and track effects. Emission equipment discrepancies *for illustration only
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