Several components are needed to effectively monitor emissions and ensure that ship performance is optimised, regulations are met, and reputation is maintained. The following two articles in this series of twelve explores some of these components including the need for high quality and accurate data, reliable fuel measurement systems, effective processing of emissions data, and a critical but often underestimated component – collaboration and transparency.
High-Quality and Accurate Data
High-quality data is important for meeting the International Maritime Organization’s Data Collection System (IMO DCS) and EU Monitoring, Reporting and Verification (EU MRV) requirements. Both require ships over 5,000 GT regardless of flag to monitor and report their emissions. However, discrepancies between the two frameworks make it difficult for owners and operators to understand their requirements.
The IMO uses fixed emissions factors to estimate CO2 output from different fuel types. However, this method assumes complete combustion, meaning all fuel is fully converted to CO2. It also assumes uniform combustion efficiency across all engines and operational scenarios. It does not account for real-world variations in fuel combustion efficiency, operational conditions, or fuel quality.
While the IMO focuses solely on reporting fuel consumption, the EU MRV regulation mandates reporting on actual cargo carried, fuel consumed, and CO2 emissions. The IMO also allows some flexibility in its method of monitoring CO2 emissions, while the EU MRV specifies four acceptable methods for emissions monitoring, with stricter requirements. These methods include bunker delivery notes, tank monitoring, flow meters, and direct emissions monitoring.
The EU MRV requires a much greater level of granularity in the data submitted. As a result, shipping companies operating in both international and EU-regulated waters must understand and comply with both IMO and EU MRV requirements. Due to the difference in emissions calculation methods, data must be consistent and of a high enough quality that ensures compliance across both frameworks.
In addition, managing data across multiple systems with different formats and standards can be complex and error-prone. High-quality data, collected and managed systematically, simplifies the integration and reporting process, reducing administrative burdens and therefore minimising the risk of human error.
The Difficulties in Back-Calculating Consumption from Emissions Data
Fuel consumption can be back-calculated from emissions data. In simple terms, this method seeks to determine how much fuel was burned to produce a certain amount of CO2. However, this method relies on standardised emission factors such as grams of CO2 per gram of fuel. It does not consider the different ways fuel is combusted and the resulting emissions, which can alter significantly depending on ship operations, engine conditions, and fuel quality.
This means that, regardless of the type of fuel burned, relying on fuel-based emissions factors for reporting CO2 emissions can lead to the worst-case emissions scenario being recorded. The IMO’s current DCS does not account for real-world variations, resulting in discrepancies between IMO emission factors and actual ship emissions.
In the next article in this series, we will explore a number of the other key components for effective emissions monitoring.Â
13 Normec Verifavia (Dec, 2016) EU MRV vs. IMO fuel consumption data collection system
For a more detailed understanding and exploration of the topics covered in this article, refer to our report, Transforming Maritime Operations: Unlocking Accurate Data for Sustainability and Compliance, commissioned by SailPlan.
