Rice husk-to-bioenergy pathways and irrigation savings in Jiangsu’s rice–wheat rotations

¹ Czech Technical University in Prague, Prague, Czech Republic
² Bukhara State Medical Institute, Bukhara, Uzbekistan

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

This article evaluates how valorizing rice husk into energy services can lower irrigation demand and stabilize on-farm power in Jiangsu's rice-wheat rotations. The study considers three conversion routes—small-scale high-efficiency combustion for heat, downdraft gasification for electricity and heat, and slow pyrolysis with biochar return— benchmarked against a pre-intervention baseline. Using open provincial statistics, plant-level operating logs, and reproducible computations for 2019-2024, we estimate husk availability, energy delivery per hectare, changes in seasonal irrigation application in rice and wheat, and indicative greenhouse gas offsets. A composite suitability index guides county-level comparisons, and matched before-after cohorts control for soil texture and groundwater depth. Results show that gasification maximizes electricity exported, while pyrolysis delivers the largest water savings when biochar is returned to fields. Across pathways, improved power reliability enables alternate wetting and drying in paddy fields and tighter deficit scheduling in wheat, reducing seasonal water application without compromising yields. The findings inform integrated bioenergy-irrigation planning under East China's water-energy constraints.