Kristoffer is working towards his PhD within the field of Lean Homogeneous Combustion, involved in a multinational EU-project called UPGRADE. The project covers several areas in engine optimization and particulate studies and minimization. The work at Chalmers will be focused on the implementation of the lean homogeneous combustion concept to reciprocating internal combustion petrol passenger car engines. Lean combustion possesses several advantages compared to the standard approach of stoichiometric combustion, providing both lower emissions and lower energy losses. The work consists of experimental studies of engines in engine test benches, from optical single cylinder engines to multi cylinder engines, using different techniques to enhance the combustion of slow burning lean charges. The goal is to extend the lean limit, i.e. highest possible air/fuel ratio supported by the engine without compromising engine stability. By extending the lean limit, fuel efficiency will increase and emissions decrease. The results will be implemented into a Volvo Car demonstration engine, later fitted inside a demonstrator vehicle which will be subjected to real driving emission testing to validate improvements.