1. Calculation of evaporative emissions with COPERT Giorgos Mellios
Brussels, 04 October 2012

2. Contents Summary of modifications to the COPERT model
Results / input to cost-benefit analysis

3. Modifications to the COPERT model

4. Parking time distribution
Average duration of parking events ≥ 120 hours: 218 h

5. Trip distance distribution
Introduce trip distribution to better estimate canister status before parking
Average distance of trips ≥ 20 km: 39 km

6. Purging strategy Purge volume as function of distance travelled:
9.66 l/km for small cars
16.68 l/km for medium and large cars
Purging increased (by 33/19) for all scenarios:
16.77 l/km for small cars
28.97 l/km for medium and large cars

7. Permeation emissions Non ethanol containing fuels:
0.6 g/day for fluorinated tanks (34% of cars)
0.2 g/day for multi-layer tanks (66% of cars)
Ethanol containing fuels (E5 – E10):
0.3 g/day additional emissions from the fuel and vapour control system
Other sources (leakage etc.): 0.2 g/day (depending on fuel volatility and temperature)

8. Durability Based on Swedish in-use data
Activated carbon efficiency decrease (for ethanol-containing fuel):
Small cars: 1% decrease every km  ~20% decrease over vehicle lifetime
Medium and large cars: 1% decrease every km  ~5% decrease over vehicle lifetime
Improved durability for scenario 3:
1% decrease every km for all cars  ~5% decrease over vehicle lifetime

9. Emissions calculations with modified model

10. Modelling of scenarios
More aggressive purging
Scenario 2
More aggressive purging
Bigger canister (size x 2)
Scenario 3
Improved durability (lower carbon degradation)
Multi-layer tanks for all cars

11. Outline of calculations performed
COPERT model adjusted to simulate different scenarios
Simulation runs with modified COPERT
Calculation of diurnal evap emissions for baseline and 3 Euro 6 scenarios
All EU-27 MS calculated
All years from 2015 to 2030 and 2017 to 2032 (depending on assumed implementation year)
Euro 6 vehicle fleet population and activity data from EC4MACS
Estimation of environmental benefits (VOC abated) for each scenario compared to baseline

12. Calculated diurnal emissions, EU (2015-2030)
Total diurnal emissions assuming all cars are equipped with multi-layer tanks Total diurnal emissions assuming 35% of small and medium cars are equipped with fluorinated tanks (except scenario 3)

13. Calculated diurnal emissions, EU (2017-2032)
Total diurnal emissions assuming all cars are equipped with multi-layer tanks Total diurnal emissions assuming 35% of small and medium cars are equipped with fluorinated tanks (except scenario 3)

14. Diurnal emission factors (2015-2030)
Average diurnal emission factors assuming all cars are equipped with multi-layer tanks Average diurnal emission factors assuming 35% of small and medium cars are equipped with fluorinated tanks (except scenario 3)

15. Observations Significant emissions reduction potential
Activated carbon quantity (canister size) and quality (related to durability) seem to have the greatest effect, followed by fuel tank structure and purging strategy
Further emissions reductions may be achieved with the introduction of OBD