Performance and environmental sustainability studies on a dual-fuel IC engine working with producer gas of variable calorific values from rural biomass

Decentralized power generation using renewable gaseous biofuels faces challenges due to their inconsistent quality and availability. Mixing producer gas (PG) with diesel as a secondary fuel is a promising option, but the non-stable calorific value (CV) of PG from different biomasses poses a serious problem for the efficient operation of a dual-fuel engine. This study aims to examine how the CV of PG from various biomasses affects a 3.75-kW dual-fuel IC engine’s performance. The experimental facility, which has a dual-fuel engine and a 115-kW thermal gasifier, tested the blends of diesel and PG from different biomasses. We chose biomass based on its availability and PG’s CV of 3.4, 4.4, 5.2, and 6.3 MJ/Nm³. For this range of CV, the efficiency, energy consumption, and fuel replacement of a dual-fuel engine vary between 20.9 and 26.6%, 17.3 and 13.5 MJ/kWh, and 10.8 and 76.9%, respectively. Furthermore, the blend with the maximum CV of PG had a 69.64% lower specific diesel consumption and an 86% higher diesel replacement rate than the blend with the lowest CV of PG. In terms of emission characteristics, the comparison showed a 2.02–7.06% reduction in NO_x and a 4.05–55.6% increase in hydrocarbons (HCs) for the tested conditions. The overall observations demonstrated that a significant enhancement in a dual-fuel engine’s performance is possible with a higher CV of PG. However, the emissions trade-offs demand additional optimization studies, as well as case-based research, in order to integrate renewable energy and emission management in smaller-scale applications across more geographies.