Total energy consumption (in %).

This study evaluates the environmental impact and economic viability of a solar-biogas hybrid dryer using life cycle assessment (LCA) and techno-economic analysis. The LCA, in accordance with ISO 14040/14044, employs a cradle-to-grave approach using the ReCiPe 2016 Midpoint method. Results indicate a global warming potential of 1,100 kg CO₂-eq per functional unit, primarily from mild steel (69.4%) and aluminium (18.8%), representing 40–50% lower emissions than solar-electric and solar-diesel hybrid systems. Total energy consumption is 9,110 MJ per functional unit, with fossil fuels dominating (82.4%), while renewable energy use remains minimal. Human toxicity is significant, with mild steel and aluminium contributing 71.6% and 13.2% to carcinogenic toxicity, respectively. Integrating biogas reduces dependence on grid electricity and lowers operational emissions by 85%. Techno-economic analysis shows capital expenditure (CapEx) of USD 3,618.20 and operational expenditure (OpEx) of USD 9,458, with a payback period of 1.3 years and return on investment of 76.39%, indicating strong economic viability. Sensitivity analysis reveals that reductions in banana prices decrease operating expenses and the payback period, while reductions in biogas costs increase net cash flow and return on investment. The dryer demonstrates lower global warming potential and energy use compared with conventional dryers, supporting its adoption for sustainable agricultural processing in sub-Saharan Africa.

本研究采用生命周期评估（Life Cycle Assessment, LCA）与技术经济分析方法，对太阳能-沼气混合干燥机的环境影响与经济可行性展开评估。本次生命周期评估遵循ISO 14040/14044标准，采用从摇篮到坟墓的评估边界，并选用ReCiPe 2016中点法开展计算。研究结果显示，单功能单位的全球变暖潜势（Global Warming Potential, GWP）为1100千克二氧化碳当量，主要排放来源为低碳钢（占比69.4%）与铝（占比18.8%），其排放量较太阳能-电力、太阳能-柴油混合系统低40%~50%。单功能单位总能耗为9110兆焦，其中化石燃料占比高达82.4%，可再生能源使用占比极低。人体毒性影响较为显著，低碳钢与铝分别对致癌性毒性贡献了71.6%与13.2%。引入沼气可降低对电网电力的依赖，并减少85%的运营排放。技术经济分析结果表明，该干燥机的资本支出（Capital Expenditure, CapEx）为3618.20美元，运营支出（Operational Expenditure, OpEx）为9458美元，投资回收期为1.3年，投资回报率达76.39%，展现出优异的经济可行性。敏感性分析显示，香蕉价格下跌会降低运营成本并缩短投资回收期，而沼气成本降低则会提升净现金流与投资回报率。相较于传统干燥机，该混合干燥机的全球变暖潜势与能耗更低，可为撒哈拉以南非洲地区的可持续农业加工提供应用支撑。