Aim of NEREAS is a complete technical solution for monitoring and optimizing the energy efficiency of merchant vessels through:

  • Speed and Trim determination for Voyage Performance Optimization, i.e.:
    • Minimized Total Fuel Consumption
    • Meeting with ports’ ETA requirements
  • Live timing vessel’s performance via big data analysis
  • Self-learning software via digital library creation that contains historical performance data of the vessel

 

Speed and Trim Optimization

Speed is one of the main factors regarding fuel consumption since it is exponentially correlated with the required power for propulsion (Picture 1). In that sense, doubling the speed would increase the required power and would also increase fuel consumption about eight times. To optimize these two variables we can focus on and exploit the following data:

  • Future Weather data collection from Weather Providers
  • Ship Specific expected Total Resistance Calculation
  • Speed changes intervals determination from the user (times per sailing day)
  • Expected Fuel Consumption calculation via Main Engine Condition Assessment
  • Optimum Speed and Trim determination for total voyage Fuel Consumption minimization

Using all the above in NEREAS platform, in a given trip, by optimizing cruising speed by 2% (based also on vessel's commercial commitments), the expected reduction in fuel consumption will be around 5%


Picture 1: Typical speed - power curve of a vessel

 

Vessel’s Performance Assessment

1. Optimize Trim 

Most vessels are designed to operate in two specific draughts with trim close to 0. Nevertheless, the real operation of the vessel is made in a wider variety of draughts and trims. Thus, it is possible that when a lightly loaded vessel travels with the wrong trim to consume more fuel than a vessel carrying more load and having the right trim. Fixing the trim can reduce the fuel consumption by 2% on average.

2. Monitor Vessel's and Propeller 's Condition

During vessels's operation, the performance decreases due to increased resistant caused mainly by marine flora. Using a system to monitor the performance, it will be possible to foresee when the vessel needs cleaning and/or the propeller needs polishing. Having a clean vessel means consuming around up to 6% lees fuel.     

3. Monitor Internal Combustion Engines

Performance of internal combustion engines depends directly on their actual state, which can be represented by their operating parameters. Thus, continuous monitoring of the operating parameters of the propulsion engine and the generators can provide the crew and the technical manager of the vessel with an early warning of their performance decrease, leading to immediate corrective actions. An engine with correct operating parameters can be 5% more efficient than a faulty one.

To implement all the above mentioned performance optimizations, the following actions are needed: 

  • Installation of Sensors for operational data collection
  • Big Data Oriented Platform’s development for data storage and analysis
  • Development of Ship Specific models for Fuel Consumption calculation
  • Main & Auxiliary Engines condition assessment (graphs / reports generation)
  • Hull Condition Assessment

 

Summing up, the final product is expected to yield on average an improvement of 3% on the vessel - user, by taking into consideration the following factors that can affect use and application of it:

  • Limitations that arise regarding vessel's speed (directions from shipper, availability on ports for loading/unloading, etc.).
  • Limitations regarding the vessel's trim (ballast loading for trimming, draught constraints at loading/unloading port, etc.) .
  • Cost and efficiency of vessel/propeller cleaning.
  • Cost and efficiency of corrective actions regarding internal combustion engines' condition.