###### Abstract  
By combining a clean fuel such as gasoline with a high efficiency thermodynamic cycle (compression ignition), it is possible to demonstrate a powertrain that is clean and efficient, thus breaking the historical trade-off between decreasing CO\({}_{2}\) and reducing criteria pollutants. The gasoline compression ignition (GCI) engine is a promising technology that can be used to improve thermal efficiency while reducing emissions. Its low temperature combustion does however lead to several problems that need to be overcome. The present study relates to a method and system for combining the advantages of GCI engine technology into a hybrid electric vehicle (HEV) to maximize the benefits. A plausible path is to operate the GCI engine at conditions where the benefits of a GCI engine could be maximized and where an electric motor can supplement the conditions where the GCI is less beneficial. In this study, GCI engines with different cetane number (CN) fuels were selected, and a hybrid simulation tool was used to address the potential of the GCI engines into hybrid electric vehicles. Co-developments can demonstrate efficiency and emission solutions through the achievements of the study, which will address examples of the competitive powertrain and will introduce more than 30% of CO\({}_{2}\) reduction vehicle by 2030. CO\({}_{2}\) reduction; gasoline fuel in a compression ignition engine (GCI); GCI hybrid electric vehicle (HEV); greenhouse gas (GHG); partially premixed combustion (PPC) 2021119934 2  
2060. Correspondingly, a recently updated technology roadmap for China targets the peaking of transport emissions by 2028, followed by reduction in emissions that is more than 20% by 2035 [8]. The role of alternative powertrains, such as electric vehicles and hydrogen fuel cells, will be critical for transport to stay within the sectoral carbon budget. China, for example, aims for new energy vehicles to account for up to 50% of new sales by 2035, with the remaining 50% comprising of energy-efficient, gasoline-electric hybrids [9]. On the other hand, the EU targets 30 million EV cars on the road by 2030 [10]. The effective rate of decarbonization, however, will depend on our ability to overcome the following challenges: (1) the speed of fleet turnover within the market; (2) the accessibility to cleaner renewable power sources, particularly in countries that are still dependent on coal; (3) the build-up of new charging infrastructures at scale; and (4) the discovery of breakthrough battery technologies to allow for large-scale penetration in all transport modes. The latter will be particularly important for the hard-to-abate transport sectors, such as aviation, marine, and heavy-duty vehicles, where a practical alternative has yet to be found. One of the many options for reducing CO2 from conventional spark-ignition engines would be to run a compression ignition (CI) engine with a gasoline-like fuel. Gasoline compression ignition (GCI) technology has been extensively studied worldwide for many years [11; 12; 13; 14; 15; 16; 17]. Aramco has considered GCI technologies from different approaches, both starting from a gasoline engine platform and a diesel engine platform. GCI primarily targets market gasoline with flexibility to explore new liquid fuels to optimize emissions and CO2 benefits in the medium/long term. Figure 1 gives an illustration of a path that could be followed that leads towards the ultimate goal of fuel and engine matching. Historically, the automotive industry has considered fuel to be a constraint when designing and improving internal combustion engines (ICEs). If fuel formulation becomes a design parameter, then fuel-engine co-optimization would provide a much larger benefit in terms of CO2 emission reduction compared to the case of solely improving the ICE. This is known as fuel and engine matching.