Emission control and carbon capture from diesel generators and engines: A decade-long perspective

Diesel generators play a crucial role in providing electricity, particularly in less developed economies. As achieving Net Zero 2050 gains more traction, it is essential to address the environmental impacts and emission contributions of diesel generators. In this paper, we review the past decade of research into diesel generator emissions and discuss technologies available to mitigate their environmental effects. Starting with a description of the market importance and environmental problems caused by the release of chemicals like nitrogen oxides (NO_X), sulphur oxides (SO_X), carbon monoxide (CO), hydrocarbons (HC), and carbon dioxide (CO₂) as well as particulate matter (soot), the paper categorises and evaluates advanced mitigation systems. These systems include After-treatment Technologies, Engine Modification Technologies, and Fuel Modification Strategies. After-treatment systems such as Diesel Particulate Filters (DPF), Diesel Oxidation Catalysts (DOC), Selective Catalytic Reduction (SCR) and Exhaust Gas Recirculation (EGR) and their recent advancement are reviewed, followed by Engine Modification technologies, including Fuel Injection Strategies, Miller Cycle and In-cylinder Combustion Control. Then, we summarise the Fuel Modification Strategies and recent developments such as Blending Biodiesel and Diesel, Nanofuel Additives to Diesel, Metal-based Additives to Diesel and blending of Alcohol and Diesel. Furthermore, the potential for retrofitting CO₂ capture technologies to diesel generators is discussed as the topic that has received less attention compared to other areas mentioned above. CO₂ abatement methods, including absorption, adsorption, algae bio-fixation, and oxy-combustion techniques and their potential to be retrofitted for diesel generators, are also discussed. The paper concludes by reflecting on the importance that these technology developments play in the United Nations Sustainable Development Goals (SDGs), specifically in promoting good health, sustainable energy, innovation, and climate action. The work aims to contribute to addressing the significant gap in the decarbonisation of diesel generators by cohesively and systematically reviewing the research topics mentioned earlier. This gap is particularly evident in the application of CO₂ abatement technologies within the context of diesel generators, and this research strives to provide a foundation for further research in this critical area to meet Net Zero targets.