How food waste helps maritime vessels achieve decarbonization goals

May 19, 2022

4 minutes, 13 seconds read

How food waste helps maritime vessels achieve decarbonization goals

Why is the maritime industry focused on decarbonization?

The maritime industry currently accounts for a small percentage of greenhouse gas (GHG) emissions — approximately 3.1% of annual global CO2 emissions according to the Third IMO GHG Study conducted in 2014. However, studies have projected that percentage will increase by 20-120% between 2012 and 2050 if the world continues to move away from using fossil fuels.

In 2018, the United Nations International Maritime Organization (IMO) ambitiously set a goal to cut the maritime industry’s GHG emissions by at least half by 2050

In June 2021, the IMO adopted Regulations 23 and 25 to the International Convention for the Prevention of Pollution from Ships (MARPOL) Annex VI which requires ships to reduce their greenhouse emissions. To do so, they have established indices to set baseline values and measurements of greenhouse gas emissions from maritime vessels called EEXI and CII.

What is EEXI?

The Energy Efficiency eXisting ship Index (EEXI) is primarily used to measure GHG emissions from transportation work. This measure focuses solely on the ship’s design parameters and does not measure real time data from ship operations.

Simplified equation:

How does EEXI affect you?

Starting in 2023, all existing maritime vessels must have an EEXI value that falls below a maximum threshold as established by the IMO. All new maritime vessels must meet the Energy Efficiency Design Index (EEDI).  All ships will receive a rating of their energy efficiency between A to E, where A is considered the best possible rating

  • Ships rated A or B will receive incentives from administration, port authorities, and stakeholders. 
  • Ships rated D or E for three consecutive years must show a corrective action to achieve an index rating of C or higher.

Currently, most ships meet the requirement level for EEXI and EEDI. However, the baseline was originally established in 2013. Starting every five years from 2015, requirement levels will become increasingly stricter.

It is estimated that fewer than 25% of shipping vessels will comply with the new EEXI requirements in 2023.

Does food waste play a role in EEXI?

Yes…and no. 

While food waste does not impact EEXI, it directly impacts GHG emissions. EEXI focuses purely on ship design parameters. However, it does not take into account greenhouse gas emissions from other activities.

Many ships are still currently using food waste solutions that involve storing the waste until they reach harbor and shores. While the organic waste is stored, it decomposes and releases methane into the atmosphere. The fuel required to transport the waste off the ship and onto land also contributes to GHG emissions. It creates an expensive cycle in which rotting waste must be carefully handled. 

Many ships such as LNG Tanker, Golar Freeze, have swapped out their food pulpers for biodigesters which are an organic waste solution that sits right in their galley. The LFC biodigester removes the need to store, handle, and transport the waste offboard. Instead, it uses a natural process in which microorganisms digest the food waste and turn it into water that can be diverted to sewage systems for filtration. Ships are able to sail without interruption and can responsibly dispose of their organic waste with the biodigester.

What is CII?

The Carbon Intensity Indicator (CII) is a measure of how efficiently a ship transports goods or passengers and calculates the CO2 emissions generated by distance traveled and capacity. 

Simplified equation:

How does CCI affect you?

CII affects all ships above 5,000 GT, including: bulk carriers, gas carriers, tankers, cargo ships, cruise ships, passenger vessels and more.

Similar to EEXI, each ship is given a rating from A to E based on their yearly CCI calculations.

Does food waste play a role in CII?

Food waste plays a much more direct and relevant role in calculating CII. Food waste greatly contributes to Scope 3 emissions. When food waste is held in storage, it produces methane. Methane is an odorant which naturally mixes with hydrogen sulfide in the air and causes a rotten egg smell. Every 100 kg of food waste generates approximately 8.3 kg of methane into the atmosphere.

All ships generate food waste during their expeditions, whether it comes from strictly crew members or passengers. Longer expeditions or a higher number of passengers will increase the annual CO2 emissions generated.

Any vessel using a food pulper will generate methane over time and must transport the waste back on shore for proper disposal.

Maritime vessels using a biodigester to digest food waste on the ship will not only bypass the need for waste management and handling, but also be able to calculate the amount of CO2 diverted from the atmosphere with waste data analytics

The LFC Cloud enables ship owners to track how much food waste is digested on a daily, weekly, and monthly basis, how much CO2e is being diverted, and can aggregate the data from multiple machines into a single dashboard or report. This information can be used for GHG emission reporting and CII index calculations.

Contact Power Knot today to learn more about how an LFC biodigester can help you meet your maritime decarbonization goals.