India is focusing on retrofitting older vehicles to utilize cleaner fuel technologies, and a recent technological advancement offers a promising solution. Researchers at UNSW have developed a retrofit system enabling existing diesel engines to run on 90% hydrogen. This innovation is expected to drastically lower carbon dioxide and nitrous oxide emissions while potentially boosting efficiency by 26%.
The system is not a complete conversion to green fuel but allows businesses to substantially reduce emissions without discarding functional assets. The system replaces the existing diesel injection system by directly injecting hydrogen into the engine, with independent control of hydrogen and diesel injection timing. A key benefit is the system’s ability to efficiently utilize lower-quality hydrogen.
The development team has demonstrated that stratified hydrogen injection produces varying concentrations within the cylinder, reducing nitrous oxide emissions below those of conventional diesel engines. This aligns with the Indian government’s plans to incorporate hydrogen processing into eco-friendly mobility. Once the necessary infrastructure is established, such retrofit kits could become commonplace.
UNSW is working to commercialize these kits, targeting fleet operators, such as those in mining, who already have hydrogen supplies. Other companies, like HYDI, are developing alternative retrofit kits that generate hydrogen on the go, requiring only occasional water top-ups. This eliminates the need for external hydrogen fueling infrastructure and may reduce fuel consumption by 5–13%.