Private and commercial motor yachts. Not subject to IMO CII unless engaged in commerce ≥ 5,000 GT. Operators use CO₂ per charter-day for sustainability reporting.
Formula
$$ \text{CO}2^\text{year} = \sum_j F_j \cdot C{f,j} $$
$$ \text{Intensity} = \frac{\text{CO}2^\text{year}}{d\text{charter}} $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $F_j$ | Mass of fuel $j$ | t | bunker log |
| $C_{f,j}$ | CO₂ factor | t CO₂ / t fuel | MEPC.364(79) |
| $Bench (Charter days / year)$ | operational benchmark | d | operations log |
| $d_\text{op}$ | Operating days | d | operations log |
Charter-industry norms: 60–90 ft yacht ~ 3–8 t CO₂/day; 100+ ft ~ 8–20 t/day. Hybrid propulsion is appearing (Sanlorenzo, Riva, Heesen) - cuts running-hours fuel by 15–25 %.
Sources
- SYBAss - Superyacht Builders Association sustainability report.
- IMO MEPC.364(79) - Cf conversion factors.