Classification society Lloyd’s Register (LR) recently released the Technical Report: NOx from marine diesel engines using biofuels document, sharing industry feedback.
The technical update follows technical insights from the outcomes of early biofuel trials in marine diesel engines, incorporating client experience and industry feedback from sea trial findings on NOx emissions when using biofuels.
According to the report, there are four key observations from the trials:
- In terms of magnitude, NOx emissions were not significantly increased across the load range, in any instances by the use of any of the biofuels trialled.
- In terms of range, the majority of the NOx emission changes resulting from the use of those biofuels were no more than that level of trial repeatability.
- Each combination of biofuel and engine has its own particular NOx emission characteristics.
- For all the biofuel trials undertaken, there were no specific engine adjustments; the NOx critical settings or operating values were retained, as given in the respective Technical Files, as they would be for the use of the petroleum derived fuels.
Commenting on the findings, LR noted that “it is very much aware that the frequency of demand for using biofuels is increasing in view of the potential of using biofuel as a drop-in fuel to reduce a ship’s carbon footprint today.”
This is leading to an increasing need to carry out sea trials and overcoming the challenges of carrying out the complex process of determining the NOx emissions from using biofuel
However, LR also notes that biofuel sea trials are increasing, in view of the drive to use renewable energy. A number of trials are carrying out further measurement of NOx emissions.
For all these trials the flag Administration and Classification societies have played a significant role in applying the requirements of the Reg 18.3.2.2 and providing the Reg 3.2 temporary exemptions necessary and generally requiring ships to carry out risk assessment related to undertaking these trials.
Until two years ago, sea trials rarely included biofuel exhaust emission measurements, with evidence often relying on land-based experience from the auto industry. However marine biofuel NOx emissions evidence is emerging following the outcomes of our trials
LR concluded.