Australian Researchers Retrofit Diesel Engine To Run On 90% Hydrogen

A research team at the University of New South Wales in Sydney, Australia, is hoping to switch gears on the future fuels debate. Engineers there, led by Shawn Kook, a professor in the university’s School of Mechanical and Manufacturing Engineering, have successfully converted a diesel engine to run as a hydrogen-diesel hybrid engine, thus reducing its carbon dioxide emissions by more than 85 percent.

Over the course of 18 months, the team developed a hybrid engine that can run using a 90 percent hydrogen-10 percent diesel fuel mix. 

“The researchers say that any diesel engine used in trucks and power equipment in the transportation, agriculture and mining industries could ultimately be retrofitted to the new hybrid system in just a couple months,” the school said in an October 7 announcement.

The project used a single-cylinder diesel engine that was modified to accept direct injections of both diesel and hydrogen. The team experimented with the timing of the hydrogen direct injection to determine power output and the effect the fuel mixture had on nitrogen oxide and carbon dioxide emissions.

Kook said the ability to retrofit engines already in use could have a huge, more immediate impact on emissions.

“We have shown that we can take those existing diesel engines and convert them into cleaner engines that burn hydrogen fuel,” Kook said. “Being able to retrofit diesel engines that are already out there is much quicker than waiting for the development of completely new fuel cell systems that might not be commercially available at a larger scale for at least a decade.”

More Efficient

The system developed by the team at the University of New South Wales, Sydney, does not require high-purity hydrogen used in the fuel cell systems, according to the school’s announcement. In addition, the research team’s Hydrogen-Diesel Direct Injection Dual-Fuel System was 26 percent more efficient than the base diesel engine, thanks to more precise fuel mixing achieved through the independent control of the hydrogen direct injection timing and diesel injection timing.

The team of researchers hopes to commercialize the system in the next one to two years. In Australia, Kook said the most immediate application of the new system will be in mining and other industrial locations where hydrogen fuel supply lines already exist. However, with the development of hydrogen fuel storage options, the system could also be applied to road, rail and waterway transportation.

“In terms of applications where the hydrogen fuel would need to be stored and moved around, for example in a truck engine that currently runs purely on diesel, then we would also need to implement a hydrogen storage system to be integrated into our injection system,” Kook said. “I do think the general technology with regard to mobile hydrogen storage needs to be developed further because, at the moment, that is quite a challenge.”