Cruising / racing sailing yachts. Power-plant used for aux and manoeuvring rather than primary propulsion. Per-running-hour intensity and sail-assist fraction tell the story.
Ship typeYachtSailing
Operational year
Fuel
Annual CO₂
t
Daily fuel
t/day
CO₂ per engine-hour
kg / h
Formula, assumptions, and limits
CO2year=j∑Fj⋅Cf,j
Symbol
Meaning
Unit
Fj
Mass of fuel j
t
Cf,j
CO₂ factor
t CO₂ / t fuel
Bench(Engine−runhours/year)
operational benchmark
h
dop
Operating days
d
Source: ISS - International Superyacht Society sustainability guide; IMO MEPC.364(79) - Cf conversion factors