Vol. 7, Issue 11, Part A (2025)

Hybrid power solutions that combine solar electricity, biofuels, and hydrogen (fuel-cell or dual-fuel) with conventional engines are emerging as practical pathways to decarbonize agricultural mechanization while maintaining operational flexibility. This review synthesizes recent advances in solar-assisted charging and agrivoltaic concepts, biofuel (biodiesel/ethanol/biomethane) utilisation in off-road engines, and hydrogen fuel-cell or hydrogen-assisted hybrid drivetrains for tractors and implements. We compare technical architectures (series hybrids, parallel hybrids, range-extenders, and modular solar-battery stations), energy-management strategies, system integration challenges (weight, ruggedisation, refuelling/recharging logistics), life-cycle environmental implications, and economics. Representative field demonstrations and modelling studies indicate that solar-assisted micro-tractors and hybrid tractors are already viable for low-range specialty tasks, while fuel flexibility with advanced biofuels and hydrogen shows promise for heavier, continuous work as infrastructure matures. Major barriers include energy density limits, capital cost, rural hydrogen and charging infrastructure, feedstock sustainability for biofuels, and standards/regulation gaps. We close with a research and pilot-deployment roadmap that prioritises duty-cycle measurement, modular hybrid demonstrators, on-farm energy integration, and circular-economy pathways for fuels and batteries.