Integrated sustainability analysis of combustion engines (ISACE) as an alternative to classical combustion analysis

A great deal of efforts has been put into enhancing the efficiency of internal combustion engines as the main contributors to environmental and health problems faced worldwide. Several well-known discrete performance and emission indicators are frequently used to evaluate and compare new designs, engine modifications, and fuel formulations. However, conventional analysis of performance and, more importantly, emission parameters is subjective because the magnitude and rating of harmfulness of the investigated indices are not equivalent to each other.‏ Moreover, this type of analysis does not ‏take into account the background information of the fuel formulations under investigation, or ‏in other words, it is solely focused on the combustion stage. These introduce ‏biases into the decision-making process. To address these challenges, we introduce an integration of conventional combustion analysis data with the life cycle assessment approach, namely Integrated Sustainability Analysis of Combustion Engines (ISACE). More specifically, first, background data of fuel formulations (cradle to tank) and combustion outputs (performance and emission parameters under different engine conditions) are converted into human health, ecosystem, climate change, and resources endpoint damage categories. In better words, the life cycle impact assessment (LCIA) quantifies the fuel production and combustion data into a manageable number, i.e., endpoints and facilitates the understanding and evaluation of the magnitude and significance of their potential environmental impacts. Finally, these endpoints having different units will be weighed and combined to achieve a single environmental score or total weighted environmental impact. This single ISACE score can now be an objective basis for the decision-making process.