Korean scientists has succeeded in developing a HCNG engine, which fulfills “Euro-6,” European emission regulations for diesel engines, for the first time in the world. This engine is compatible with existing natural gas engines. Thus, it is possible to change natural gas buses into HCNG buses with the new engine.
The research team led by Dr. Kim Chang-ki of the green power development division at the Korea Institute of Machinery & Materials (KIMM) announced on March 24 that it has developed the HCNG engine, which is environmentally friendly and has high performance, based on excellent combustion characteristics and cleanness of hydrogen.
HCNG is a vehicle fuel which is a blend of hydrogen and compressed natural gas (CNG). Since it emits less exhaust gases and has better combustion performance than CNG, it can be used as a fuel of existing CNG vehicles. Advanced countries, such as the United States, Germany, France and Norway, consider HCNG the most effective fuel that will lead the future hydrogen energy era. Accordingly, they have been developing a HCNG engine from the early 2000, but they haven’t developed the engine that meets Euro 6 emission standards yet.
The research team has improved the durability and fuel efficiency by using a “High EGR technology,” which controls the combustion temperature and oxygen concentration by recirculating a portion of an engine's exhaust gas back to the engine cylinders. The new engine emits 18 percent less carbon dioxide but has 8 percent higher fuel efficiency than the CNG engine with the same output. As the researchers reduced its all toxic exhaust emissions to one third of the current Euro 6 emission standards, the new engine is expected to fulfill the Euro 7 emission standards, which will take effect from 2020, with ease. Currently, the research team is test operating the HCNG engine after applying it to two intra-city buses in Ulsan and Incheon.
Dr. Kim Chang-ki said, “We have developed a HCNG engine, which satisfies emission regulations after the Euro 6, for the first time in the world. It is meaningful in that we have set a foundation to commercialize HCNG buses. Once HCNG charging infrastructure is constructed, we expect to commercialize them within three years.”