**4. Conclusion**

Organic waste management is very critical in most of the developing countries in hot and humid conditions. It can pollute the environment including the surface water pollution and air pollution. These studies illustrate that the planet's tiniest inhabitants can address two of biggest environmental challenges our society faces today: generating clean renewable energy and handling vast quantities of organic waste. Through these studies, it is proven that MFCs are practical technology for the aforementioned problems. The generated bioelectricity can power devices such as LED lamps, phones, and geo-environmental sensors. Various kinds of organic waste such as livestock waste, kitchen garbage, agricultural waste can be used as a source of biomass for bioelectricity generation through MFC. The nutrient contents of the by-products of the MFC are rich and in a suitable range of a compost. Furthermore, the by-products from the decomposition of organic waste accelerated with the use of MFC can be used as soil conditioner, increasing the soil's organic content, and as a fertilizer to aid plant growth. In fact, there will be no by-product of generating bioelectricity by using the organic waste. The applicability of this study's results extends to both developing and developed countries where solid waste management and or sourcing of energy is a great concern. However, the future challenges for this research including the sustainable supply of organic waste will be a major problem in the industrialized parts of the world. Nevertheless, it can solve the problem of the waste management problems in the developing countries. In the future, the biomass such as algae can be used in the MFCs to generate the bioelectricity. MFCs can contribute to the maintenance of a healthy and pollutants-free environment for the future generation.
