The Carbon Intensity Indicator (CII) is a measure introduced by the IMO (International Maritime Organization) to assess the efficiency of ships in terms of CO₂ emissions relative to the amount of cargo transported and the distance traveled.

The formula for CII is typically as follows:

$\text{CII} = \frac{\text{Annual CO}_2 \text{ emissions}}{\text{Annual Cargo Carried (MT)} \times \text{Annual Distance Traveled (NM)}}$

Given the data provided, the steps to compute the CII involve:

1. Calculate the CO₂ emissions from High Sulphur Fuel Oil (HFO) consumption.
2. Calculate the CO₂ emissions from Marine Diesel Oil (MDO) consumption.
3. Sum the total CO₂ emissions.
4. Calculate the CII using the formula.

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Step 1: CO₂ Emissions from HFO Consumption

• Total HFO consumed during travel: 397.4 mt
• CO₂ emission factor for HFO: 3.114 t CO₂ / t

$\text{CO}_2 \text{ from HFO} = 397.4 \, \text{mt} \times 3.114 \, \frac{t \, \text{CO}_2}{t} = 1237.61 \, \text{t CO}_2$

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Step 2: CO₂ Emissions from MDO Consumption

There are three types of MDO consumption mentioned:

1. MDO consumed in port with refrigeration power:
   • MDO consumed: 815.387 mt
   • CO₂ emission factor for MDO: 3.206 t CO₂ / t

$\text{CO}_2 \text{ from MDO in port} = 815.387 \, \text{mt} \times 3.206 \, \frac{t \, \text{CO}_2}{t} = 2613.83 \, \text{t CO}_2$

2. MDO consumed during travel with refrigeration power (905.6 kW for 403.9 hours):
   • MDO consumed: 151.85 mt

$\text{CO}_2 \text{ from MDO with refrigeration power} = 151.85 \, \text{mt} \times 3.206 \, \frac{t \, \text{CO}_2}{t} = 486.99 \, \text{t CO}_2$

3. MDO consumed during travel without refrigeration power (340.3 kW for 410.9 hours):
   • MDO consumed: 151.85 mt

$\text{CO}_2 \text{ from MDO without refrigeration power} = 151.85 \, \text{mt} \times 3.206 \, \frac{t \, \text{CO}_2}{t} = 486.99 \, \text{t CO}_2$

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Step 3: Total Annual CO₂ Emissions

Now, we can sum up the CO₂ emissions from all sources:

$\text{Total CO}_2 = 1237.61 \, \text{t} + 2613.83 \, \text{t} + 486.99 \, \text{t} + 486.99 \, \text{t} = 4825.42 \, \text{t CO}_2$

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Step 4: Calculate the CII

Using the CII formula:

$\text{CII} = \frac{\text{Total CO}_2}{\text{Annual Cargo Carried (MT)} \times \text{Annual Distance Traveled (NM)}}$

Substitute the given values:

• Annual Cargo Carried: 16376.173 MT
• Annual Distance Traveled: 8059.1 NM

$\text{CII} = \frac{4825.42 \, \text{t CO}_2}{16376.173 \, \text{MT} \times 8059.1 \, \text{NM}} = \frac{4825.42}{131993062.2} = 0.03656 \, \text{gCO}_2/\text{t-nm}$

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Conclusion:

The Carbon Intensity Indicator (CII) for the Refrigerated Cargo Ship is 0.03656 gCO₂/t-nm.

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Would you like further details on any specific part of the calculation?

Here are five related questions to deepen understanding:

1. How does the CII vary with different cargo weights?
2. What is the significance of using different fuel types in the calculation?
3. How does CII influence regulations for shipping companies?
4. What measures can reduce CO₂ emissions and improve CII?
5. How does the time spent in port affect total emissions?

Tip: To improve CII, optimizing fuel consumption during both travel and port stays is critical, as is reducing total emissions by selecting more energy-efficient routes and engines.