Syngas from biomass and solid waste is a carbon-neutral fuel believed to be a promising fuel for future engines. It was widely
used for spark-ignition engines in the WWII era before being replaced with gasoline. In this paper, the technological development,
success, and challenges for application of syngas in power generating plants, the trends of engine technologies, and the potential
of this fuel in the current engine technology are highlighted. Products of gasification vary with the variation of input parameters.
Therefore, three different syngases selected from the two major gasification product categories are used as case studies. Their fuel
properties are compared to those of CNG and hydrogen and the effects on the performance and emissions are studied. Syngases
have very low stoichiometric air-fuel ratio; as a result they are not suitable for stoichiometric application. Besides, syngases have
higher laminar flame speed as compared to CNG. Therefore, stratification under lean operation should be used in order to keep
their performance and emissions of NOx comparable to CNG counterpart. However, late injection stratification leads to injection
duration limitation leading to restriction of output power and torque. Therefore, proper optimization of major engine variables
should be done in the current engine technology