This study investigates the cost–benefit analysis and financial viability of biogas plant investment in South Ethiopia. A multi-stage sampling technique was employed to select sample households. A total of 105 adopter households were selected for household survey using a purposive sampling technique. All the households adopting biogas technology were considered. Besides, a biogas plant with 6 m3 and 8 m3 sizes were selected because they were the most commonly used size in the study area. Data were collected from the household survey, key informant interviews, focus group discussion and market price assessment. The installation cost took the largest share of the total cost of construction and was one of the main constraints that hindered adoption. The findings of the study indicate that the production of biogas increased household income by reducing the costs incurred for buying firewood, kerosene and chemical fertilizers. Relatively, lower plant size was more profitable than larger plant size. Installation under the subsidy scheme was more financially viable at 10% discount rate than its counterparts. Subsidy is important to enhance biogas plant investment, particularly for larger biogas plant sizes. Nevertheless, both plant sizes, installed without subsidy, had smaller NPV values and UDBP greater than 1 year, making this scenario financially less viable. Installation of low cost plants could more attract the engagement of a large number of rural households with low economic capacity. However, both plant sizes (6 m3 and 8 m3) are financially viable and profitable at 10% discount rate. Moreover, the profitability of biogas investment is highly sensitive to variation in discount rates, level of expenditure savings and input prices.

中文翻译：

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埃塞俄比亚南部家庭沼气厂投资的成本效益分析和财务可行性


本研究调查了埃塞俄比亚南部沼气厂投资的成本效益分析和财务可行性。采用多阶段抽样技术来选择样本家庭。采用立意抽样技术，共选取105户收养户进行入户调查。所有采用沼气技术的家庭都被考虑在内。此外，选择了 6 m3 和 8 m3 尺寸的沼气厂，因为它们是研究区域最常用的尺寸。数据来自入户调查、关键知情人访谈、焦点小组讨论和市场价格评估。安装成本在建筑总成本中所占比例最大，是阻碍采用的主要制约因素之一。研究结果表明，沼气生产减少了购买木柴、煤油和化肥的成本，从而增加了家庭收入。相对而言，较小的工厂规模比较大的工厂规模更有利可图。补贴计划下的安装在 10% 的贴现率下比同类安装在财务上更可行。补贴对于增加沼气厂投资非常重要，特别是对于规模较大的沼气厂。然而，两种规模的电厂在没有补贴的情况下安装，其 NPV 值较小，且 UDBP 大于 1 年，使得这种方案在财务上不太可行。低成本电站的安装更能吸引大量经济能力较低的农户参与。然而，两种规模的工厂（6 m3 和 8 m3）在财务上都是可行的，并且可以按 10% 的折扣率盈利。此外，沼气投资的盈利能力对贴现率、支出节省水平和投入价格的变化高度敏感。