(PRNewswire)--Diamond & Zebra Electric, an Osaka-based group company of Diamond Electric Holdings, has achieved a significant level of ammonia combustion technology in the development of a new ignition system, the vital component in fuel combustion to make use of reciprocating engines in a carbon-neutral society. Diamond & Zebra published the achievement through a thesis presented at the 2023 JSAE Annual Congress (Spring) held by the Society of Automotive Engineers of Japan (Conference Session No. 30: Advanced Gasoline Engine Systems and Technologies I).

In recent years, studies on carbon-free combustion of ammonia fuel have been progressing along with vehicle electrification efforts as a measure against global warming. One of the factors for stable combustion of hard-to-burn fuels such as ammonia, as opposed to conventional gasoline, requires an extremely high-energy spark discharge in the ignition system.

As a manufacturer with ignition combustion technology expertise, Diamond & Zebra established A-Lab (Combustion Laboratory) in 2018 within its group company Diamond Electric Mfg. Co., Ltd., based in Tottori, Japan. A-Lab has been independently conducting basic research on ammonia and H₂ combustion, using a special ignition device that can freely change the discharge energy and current characteristics of ignition coils. As a result, stable combustion at a higher ammonia-mixing ratio, up to 100% ammonia, was achieved in an experiment with a typical reciprocating engine using a mixture of ammonia and H₂ as fuel. Stable combustion with 100% ammonia fuel is the world's first achievement as far as publicly disclosed.

Based on the research result, Diamond & Zebra has started the development of an ultra-high energy ignition system, which is a combination of ignition coil technology capable of outputting six times more ignition energy than its conventional products and multi-ignition technology enabling multiple spark discharge at the 1/1000-second level to boost its ignition energy more than 12 times as the system output: all in a compact size to be mountable on an engine.