Cooperation between KOGAS, KGS (Korean Gas Safety), KIMM (Korea Institute of Machinery & Materials) and Daewoo Bus has enabled scientists to develop an HCNG engine which is compliant with Euro 6 emissions regulations. This engine, as reported by Business Korea, is compatible with existing natural gas engines, making it possible to change natural gas buses into HCNG buses with the new engine.
HCNG is hydrogen-enriched compressed natural gas; it emits less exhaust gases and has better combustion performance than CNG, and is considered by many as a a stepping stone to hydrogen fuel as a future energy source. Although significant work has been carried out over several years on HCNG engines, the research team claims this is the first Euro 6 compliant engine.
High EGR (exhaust gas recirculation) technology has reportedly brought about improvements in durability and fuel efficiency, controlling combustion temperature and oxygen concentration by recirculating a portion of the engine’s exhaust gas back to the engine cylinders. The new engine emits 18% less carbon dioxide but has 8% higher fuel efficiency than a CNG engine with the same output.
Furthermore, the emissions outcomes are so good, the research team has expressed confidence the new technology will satisfy compliance requirements for Euro 7 emissions standards, which will take effect from 2020.
Dr. Kim Chang-ki, who is leading the research, says, “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 3 years.”
Field testing of two buses is currently being conducted.