EGR Rate for Tier III Compliance
Approximate Exhaust Gas Recirculation rate required to reduce engine-out NOx to Tier III limit without urea.
Required NOx reduction
0.8%
Estimated EGR rate
30.5%
Formula, assumptions, and limits
Empirical simple correlation for two-stroke marine diesels (MAN ME-GI / ME-LGIP). ~25–30 % EGR typically gets to Tier III. EGR also raises PM and BSFC ~3–5 % - trade-off vs SCR's urea cost.
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| Engine-out NOx at 0 % EGR | g/kWh | NOx Technical File | |
| Tier III limit | g/kWh | MARPOL Annex VI Reg 13 |