The new system retrofits diesel engines to operate with 90% hydrogen.
The team from the Engine Research Laboratory of the University of New South Wales in Australia has developed a new hydrogen diesel direct injection dual fuel system, which greatly reduces carbon emissions. Engineers at the University of Sydney have successfully converted a diesel engine into a hydrogen diesel hybrid engine for operation -- in the process, carbon dioxide emissions have been reduced by more than 85%.
The team led by Professor Shawn Kook of the School of Mechanical and Manufacturing Engineering of the University of New South Wales in Australia spent about 18 months to develop a hydrogen diesel direct injection dual fuel system, which means that existing diesel engines can operate with 90% hydrogen as fuel.
The researchers said that any diesel engine used in trucks and power equipment in transportation, agriculture and mining could eventually be converted into a new hybrid system in just a few months.
Green hydrogen is produced from clean renewable energy such as wind energy and solar energy, which is more environmentally friendly than diesel.
In a paper published in the International Journal of Hydrogen Energy, Professor Cook's team showed that the use of their patented hydrogen injection system could reduce carbon dioxide emissions to only 90 g/kWh - 85.9% less than the amount generated by diesel powered engines.
This new technology significantly reduces the carbon dioxide emissions of existing diesel engines, so it can play an important role in significantly reducing our carbon footprint, especially in Australia, all of our mining, agriculture and other heavy industries that widely use diesel engines.
"We have proved that we can use existing diesel engines to convert them into clean engines burning hydrogen fuel. It is much faster to transform existing diesel engines than to wait for the development of new fuel cell systems, which may not be commercialized on a large scale for at least ten years. With the problems of carbon emissions and climate change, we need some more direct solutions to deal with many of the problems currently used Diesel engine problems. "
High pressure hydrogen direct injection
The University of New South Wales team's solution to this problem has maintained the original diesel fuel injection into the engine, but added hydrogen fuel injection directly into the cylinder.
The cooperative research conducted with Dr. Shaun Chan and Professor Evatt Hawkes found that the specially timed hydrogen direct injection controlled the mixing condition in the engine cylinder, thus solving the harmful NOx emissions, which has been the main obstacle to the commercialization of hydrogen engines.
"If you just put hydrogen into the engine and mix them together, you will emit a lot of nitrogen oxides (NOx), which is an important reason for air pollution and acid rain." Professor Cook said: But we have shown in our system that if you layer it - that is, there is more hydrogen in some areas and less hydrogen in other areas - then we can reduce NOx emissions to less than those of pure diesel engines. "
Importantly, the new hydrogen diesel direct injection dual fuel system does not require extremely pure hydrogen, and hydrogen must be used to replace the hydrogen fuel cell system, and the production cost is higher. Compared with existing diesel engines, the efficiency of diesel hydrogen hybrid electric vehicle is improved by more than 26%. The efficiency is improved by independently controlling the direct hydrogen injection timing and diesel injection timing, so that the combustion mode - premixed or mixed controlled hydrogen combustion can be fully controlled.
The research team hopes to commercialize the new system in the next 12 to 24 months and is keen to negotiate with potential investors. They said that the most direct potential use of this new technology is in industrial sites where permanent hydrogen fuel supply lines have been established.
This includes mining sites. Research shows that about 30% of greenhouse gas emissions are caused by diesel engines, mainly used for mining vehicles and generators. The diesel generator market in Australia is currently estimated at approximately US $765 million.
"At the mine where hydrogen is piped, we can convert existing diesel engines for power generation."
Professor Kook said:
"As far as the applications that need to store and move hydrogen fuel are concerned, for example, in the current pure diesel truck engine, we also need to implement a hydrogen storage system to integrate into our injection system. I do think that the general technology of mobile hydrogen storage needs to be further developed, because it is a considerable challenge at present."
