MOBILE SOURCE EMISSION INVENTORY FOR THE CITY

OF CAPE TOWNDAPPS Report-back Meeting

Juliet Mert & Eugene Cairncross

Peninsula Technikon

27 November 2003

OVERVIEW

DAPPS requirementsMethodology (Toolkit and Manual method)ResultsDiscussions/ConclusionAcknowledgements

DAPPS Requirements

For mobile source emissions, DAPPS requires strip source emission rates of CO, HC, NOx, PM & SOx [g pollutant/s per strip].

The IPIECA Toolkit predicts total mobile source emissions in the CMA(i.e. a mobile source emission inventory).

A spreadsheet was setup in an attempt to determine temporal and spatial emissions.

Methodology

TOOLKIT METHOD

• The IPIECA Toolkit is an emission inventory model, developed by IPIECA (UAQM)

• The model estimates emission rates based on: vehicle kms traveled, fuel consumption rates, annual human and vehicle population growth rates.

Toolkit Results

Petrol consumed (kT/a) Diesel consumed (kT/a)

Modeled Est actuala Modeled Est. actual

1995 870 953 595 510

1998 972 1022 686 559

2001 974 971 691 609

Total Petrol and Diesel Consumption, Modeled vs Actual

Total Lead emissions (kT/annum)

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Year

Pb (k

T/a

)Particulate Matter emissions (kT/annum)

0

1

2

3

4

5

6

Year

PM (k

T/a

)

Total Car Gasoline non-catTotal Car Gasoline catTotal Diesel CarsTotal Motor- cyclesTotal Commercial vehiclesTotal Mobile Emissions

Hydrocarbon emissions (kT/annum)

0

5

10

15

20

25

30

35

40

Year

HC

(kT

/a)

Total Car Gasoline non-catTotal Car Gasoline catTotal Diesel CarsTotal Motor- cyclesTotal Commercial vehiclesTotal Mobile Emissions

Base year [2001] Pollutant levels

0

10

20

30

40

50

60

70

80

90

PM SOx VOC NOx

Pol

luta

nts

[kT

/ann

um]

Base Year Pollutant Levels

Methodology

MANUAL METHOD• Basis: vehicle counts (for the CBD), ave.

speeds, emission factors (EF) and route distances.

• Vehicle counts obtained from the Annual Vehicle Screenline Survey for Cape Town CBD (2001). Counts were done at 11 points in the City centre.

• Route distances were physically measured then sectioned into zones.

City map

Section of CMA map

Study area boundary

Counting stations boundary

Manual Results

Zone Average Distance

Speed (LV)

EF example of CO

CO emission/ annuma

Toolkit estimate

Differenceb

km km/hr g/km kT/annum kT/annum %

1 40 50 24 14.9 206 25

2 25 20 43 17.3 - -

3 24 15 51 19.3 - -

Total - - - 51.5 - -

aEmission = zone distance*vehicles/hour*EF [g/h]b60% of vehicles accounted for in CMA

Discussion/Conclusion

• There is a good match between Toolkit total fuel consumption and fuel sales figures.

• The accuracy of estimated total and strip source emissions relies on valid assumptions, area boundaries and quality of data (such as vehicle counts).

Acknowledgements

• CSIR• Pentech• SKR• SAWB• Naamsa, Sapia,

Sapref, City of Cape Town

*DAPPS is funded by the DACST’s Innovation Fund, administered by the NRF.