NETHERLANDS IN-SERVICE EMISSION TESTING PROGRAMME FOR HDV: REAL-WORLD NOX EMISSIONS OF EURO VI REFUSE COLLECTION VEHICLES

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1 NETHERLANDS IN-SERVICE EMISSION TESTING PROGRAMME FOR HDV: REAL-WORLD NOX EMISSIONS OF EURO VI REFUSE COLLECTION VEHICLES Robin Vermeulen Brussels, HD PEMS working group, May 18

2 1. INTRODUCTION: OBJECTIVES, APPROACH General objectives Commissioned by the Ministry of the Infrastructure and Water Management TNO regularly tests the emissions of heavyduty vehicles in the in-service emissions testing program. The measurements are done: 1) to determine the real-world emissions levels (trends, emissions factors) and 2) to screen the in-service conformity. Euro VI vehicles in general have on average low NOx emissions compared to previous generations [TNO, 16]. However, varying NOx levels have been observed for some applications. Especially for urban, low speed and low load driving. Due to NO2 exceedances in cities (AQ), vehicles need not only be clean on average but also for urban driving. -> Test RCVs, buses, distribution trucks in daily operation to determine real-world NOx emissions Approach Method used: On-road emissions test. Test routes: Daily operation (~2 weeks -few months of continuous measurement). In-service conformity screening: applicable ISC trips N1, N2, N3, M2, M3 Instrumentation: Smart Emission Measurement System (SEMS).

3 2. TEST METHODS On-road tests are mainly carried out by TNO with SEMS and/or PEMS measuring equipment. SEMS Smart Emissions Measurement System (used for this test programme) PEMS Portable Emissions Measurement System (prescribed for formal EU in-service emissions testing according EC Regulation 582/11) SEMS PEMS 1 EU/11/582 and amendments

4 2. TEST METHODS: METHOD USED SMART EMISSION MEASUREMENT SYSTEM (SEMS) Autonomous: auto start and stop, data writing and data transmission to TNO online SEMS database server via GRPS NO x O 2 sensors post SCR/LNT NH 3 sensor post SCR Thermocouples: post SCR/LNT (EGT: Exhaust Gas Temperature) GPS (Vehicle speed and position) OBD-signals (whenever available: engine coolant temperature, engine speed, engine torque, fuel rate, manifold air flow/pressure) Data logger (1 Hz) The methodology is further described in: Spreen J.S., et al., Assessment of road vehicle emissions: methodology of the Dutch in-service testing programmes, TNO report TNO 16 R11178, October 16

5 2. TEST METHODS: ONLINE SEMS DATABASE

6 3. VEHICLE SELECTION Based on ranking of nr. of engine registrations Euro VI step A 8 diesel, 1 LNG Obtained from operators 5 side or rear small container loaders of which one with plugin e-pto 1 garbage bag rear loader 1 large underground container top loader 1 open container vehicle simulated by a rigid of the same mass purchasing vehicle during regular ops. 1 top loader + container cleaner vehicle

7 4. RESULTS: REAL WORLD OPERATION DIFFERS Veh. Type Time Average engine power Average Distance speed [km] [h] [km/h] [%] % time speed =, engine running % cold engine Type of operations T coolant <C [%] [%] Small container n.a. 54 n.a. Domestic refuse, urban Small container Domestic refuse, urban Small container Domestic refuse, urban Small container Domestic refuse, urban and rural Container cleaner Container cleaning, urban and rural Small container Domestic refuse, urban Open container n.a. Domestic coarse refuse, urban Large underground container Domestic refuse, urban, underground container Small container e-pto Domestic refuse, urban

8 4. RESULTS: REAL WORLD OPERATION DIFFERS DA141 Small container IV153 Small container MB156 Container cleaner GI172 Larger underground container IV161 Open container coarse refuse SC149 Small container DA157 Small container SC125 Small container

9 NOx [g/kwh] 4. RESULTS: AVERAGE NOX EMISSIONS D 1 D D D LNG D D D Average speed[km/h] 1 Test vehicle, a rigid truck, chased RCV in real operation. Results represent worst case conditions not favourable for NOx reduction. (Tamb ~ to -2C, low payload, no aut gear box, no use of small crane). Results of 1 test vehicle not depicted: 1 test vehicle had white deposits inside end of tail pipe and on sensors. The results of the fouled sensors are probably influenced by sublimation of deposits when exhaust gas is ~>175C.

10 4. RESULTS: NOX -MIN MAW Distribution -min MAW emissions in gnox/kgco2 1 g/kgco2 equals approx..69 g/kwh About half of the MAW >1 g/kg

11 Post SCR exhaust gas temperature [C] 4. RESULTS: EXHAUST TEMPERATURE Average exhaust gas temperature post SCR Average speed [km/h]

12 4. RESULTS: ENGINE POWER min-maw average power

13 4. RESULTS: NH3 Accuracy > ppm limited due non linearity of sensor. Values > ppm are indicative.

14 5. CONCLUSIONS Varying operations in terms of average speed and power also due varying auxiliary PTO power: 6 to 26 km/h Average NO x emissions vary.3 to 2.3 g/kwh for 6 out of 8 diesel vehicles One diesel vehicle had white deposits in exhaust. Measurement void due sensor fouling but indicates very high NO x and NH 3 emissions One diesel vehicle in an extreme case emits 9 g/kwh One LNG vehicle emits on average.7 g/kwh Large fraction of high temporal/local NO x emissions Sometimes high average NH 3 emissions, often also high temporal NH 3 emissions Engines of Euro VI certified RCV s are probably tested in an N3 chassis over an N3 trip Hence, a PEMS test does not match real-world operation of RCV s

15 THANK YOU FOR YOUR ATTENTION