Experimental Study on Jelantah Methyl Ester Biodiesel as a Green Technology Alternative Fuel and Its Impact on Diesel Engine Performance

Abstract The global energy crisis has prompted the search for environmentally friendly and renewable alternative fuels within the broader framework of green technology. This study evaluates the performance of a diesel engine using biodiesel blends derived from waste cooking oil (Jelantah Methyl Ester/JME) in ratios of B35, B45, and B55, compared to pure diesel fuel. The biodiesel was produced through filtration, heating, transesterification, separation, washing, and drying, positioning JME as a green-technology pathway for circular-economy waste-to-fuel conversion. Engine performance testing was conducted at 1800–2100 RPM and 1000–4000 W loads, with analysis of power output and specific fuel oil consumption (SFOC). The results showed that JME blends, particularly B35 and B55, delivered competitive power output compared to diesel, although fuel consumption tended to be higher at maximum load. The B35 blend demonstrated the highest thermal efficiency at 25.57%, compared to diesel at 15.19%. These findings suggest that JME biodiesel is a viable green-technology alternative fuel, with further optimization needed to improve fuel efficiency while sustaining environmental gains.