The trial of an emulsified fuel carried out last year by New Zealand’s ferry operator Interislander has reported reductions in specific fuel consumption of 3 per cent.
The success of this trial will further boost confidence in the application of emulsified fuel technology to larger-scale marine engines.
The trial, supported by New Zealand’s Energy Efficiency and Conservation Authority’s (EECA’s) Technology Demonstration programme, showed a 3% to 5% saving in the fuel consumed in the generator engine of the ferry and reduced particulate emissions due to more complete combustion. The trial included a month of monitored running on normal fuel to give a base line, along with pre and post-trial internal engine inspections.
The resulting report, compiled in September 2015 following monitoring by an independent fuel consultant, noted that in addition to the improved fuel consumption, the trial also showed a small improvement in the base engine performance, believed to be due to a cleaning function of the fuel. The report notes that once the test had finished, the engine showed about 2 per cent better consumption on its normal fuel.
Also specified in the report was: “internal inspection of the combustion chamber and part of the exhaust did find a reduction in the amount of soot after operation on emulsified fuel and this cleaner state of the engine may be the reason.”
Leigh Ramsey, Managing Director Blended Fuel Solutions New Zealand Limited, detailed the process by which his emulsified fuel is created, stored and used: “The fuel needs to be pre-processed to create emulsion, and requires no engine modification to run.”
“An emulsion is made when one substance coats another, in this case an oil and water emulsion is made in a high-shear mixer using an additive to keep it stable. This was done on board in-line, just prior to use.”
Interislander, Strategy Manager, Peter Wells says that the outcome of the trials could lead to significant fuel savings across the wider Interislander fleet. “The outcome looks as though it could reduce our use of fuel and the level of emissions as well as giving us a significant financial saving.” he stated.
