Abstract
Abstract Agricultural machinery relies heavily on diesel, creating a need for cleaner and more sustainable fuel options. This study investigates the blends of diesel with a small proportion of biodiesel, combined with varying amounts of ethanol and ethylene glycol, to evaluate their effects on fuel characteristics and engine efficiency. Fuel properties were assessed according to ASTM standards, and performance was analysed using exergy principles. Results indicate that ethanol tends to reduce density and viscosity, while ethylene glycol has the opposite effect. Biodiesel slightly lowers efficiency under light loads but improves performance under moderate to high loads. Certain blends exhibit minimal energy losses and demonstrate enhanced efficiency at higher engine demands. These findings suggest that carefully formulated biofuel blends can support more sustainable and energy-efficient operation of agricultural machinery.