Hybrid application of biogas and solar resources to fulfill household energy needs: A potentially viable option in rural areas of developing countries

• Techno-economic viability of hybrid biogas and solar PV system is evaluated.
• Saving from displacing conventional fuels is more than the cost of new fuels.
• The hybrid systems remain feasible for a wide range of cattle dung price.
• Majority (73%) of the biogas plant households are satisfied with biogas services.

The absence of clean cooking facilities and electricity means billions of rural people are deprived of much needed socioeconomic development. Livestock residues (dung) and solar radiation are two renewable energy resources that are abundantly available in rural areas of developing countries. Although it is not feasible for these two resources separately to meet both thermal (cooking) and electricity demands, hybrid applications have not been given due attention. To facilitate integrating these two resources in rural energy planning, and to promote their dissemination through hybrid applications, it is necessary to evaluate their economic merits, and assess their ability to deal with the demands. In this paper, we examine the techno-economic performance of hybrid applications of these two resources by applying a simulation technique using the HOMER tool, and by giving derived cost-saving equations. We also quantify the monetary savings from replacing traditional fuels, and perform a sensitivity analysis on a number of variables (e.g. dung cost, fuelwood cost) to see how they affect the performance of different energy supply alternatives. Furthermore, we examine the practical applicability of the biogas system in the households through a structured survey of 72 ongoing household biogas plants. This study finds that households that have between three and six cattle can potentially meet their cooking and electricity loads through a hybrid implementation of biogas and solar PV (Photovoltaic) system. By replacing conventional fuels households can achieve savings that are more than the total annualized costs incurred for installing new services.