Table 4.
Emission factors used for this studya
| Emission | Emission factor (g kW−1 h), Normal (80%) load | Emission factor (g kW −1 h), low (25%) load |
|---|---|---|
| NOxb | ||
| Tier 1 engine | 17 (SSD), 12.9 (MSD)b, 9.8 (HSD) | 17 (SSD), 12.9 (MSD)b, 9.8 (HSD) |
| Tier 2 | 14.4 (SSD), 10.5 (MSD), 7.7 (HSD) | 14.4 (SSD), 10.5 (MSD), 7.7 (HSD) |
| Tier 3 | 3.4 (SSD), 2.6 (MSD), 2 (HSD) | 3.4 (SSD), 2.6 (MSD), 2 (HSD) |
| SOxc | ||
| 0.1% sulphur (S) | 0.48 (MDO/MGO: SFOC 250 g kW−1 h) | 0.54 (MDO/MGO SFOC 282 g kW−1 h) |
| 0.5% S | 2.40 (MDO/MGO: SFOC 250 g kW−1 h) | 2.7 (MDO/MGO SFOC 282 g kW−1 h) |
| 2.7% S | 8.35 (HFO: SFOC 165 g kW−1 h) | 9.42 (HFO: SFOC 186 g kW−1 h) |
| CO | 0.54 | 2.18 |
| PM | ||
| 0.1% S | 0.38 | 0.43 |
| 0.5% S | 0.50 | 0.57 |
| 2.7% S | 1.19 | 1.35 |
| CO2d | ||
| HFO | 515 (SFOC 165 g kW−1 h) | 580 (SFOC 186 g kW−1 h) |
| MDO/MGO | 803 (SFOC 250 g kW−1 h) | 905 (SFOC 282 g kW−1 h) |
SSD slow speed diesel, MSD medium speed diesel, HSD high speed diesel, MDO marine distillate oil, MGO marine gas oil, SFOC specific fuel oil consumption, HFO heavy (residual) fuel oil
a Values only indicate the range of values applied on case-by-case basis because fuel consumption and emissions depend on engine load and specific fuel oil consumption (SFOC), calculated from vessel-specific automated identification system (AIS) data, as described in published literature for STEAM20, 21, 63, 64
b As defined in MARPOL Annex VI, Regulation 13. For MSD, crankshaft rpm of 514 is assumed in this example, but engine specific values are used in each case. For Tier 0 engines, 110% of Tier I value is used
c Part of sulphur is as gaseous SO2 and part is in aerosol SO4. The emission factors listed for SOx contain the gaseous emission part, the aerosol sulphur has been subtracted to maintain mass balance of sulphur
d SFOC changes as a function of engine load.0 The values listed include this effect and includes the differences in carbon content between HFO and MDO/MGO