# Strategies for Enhancing Extracellular Electron Transfer in Environmental Biotechnology: A Review
## 4 Challenges and Future Directions
This phenomenon may also serve to bolster the stability and structure of biofilms, as a well-organized biofilm can improve the effectiveness of EET mechanisms by creating a conducive environment for microbial adhesion and electron transfer. * Managing and controlling biofouling: The modification of surfaces involved in EET systems has the potential to mitigate the occurrence of biofouling. One such approach is the utilization of electrode materials possessing anti-fouling capabilities [139]. As biofouling is frequently driven by biofilm production, techniquesaiming at stimulating the formation of conductive biofilms through the selection of electrode materials that enable the growth of conductive biofilms can be beneficial. Furthermore, efforts for controlling biofilm thickness and composition will aid in maintaining a balance between the advantages of biofilm-mediated electron transfer and the possible disadvantages of excessive biofilm growth. * Introduction of energy storage and hybrid systems and smart grid technologies: Energy storage technologies, such as batteries and pumped hydro storage [140], can efficiently store surplus energy created during periods of high production and subsequently release it during periods of low output. By incorporating these storage devices with sustainable energy sources, the variations in power availability can be alleviated, hence offering a more uniform and reliable power provision for EET operations. Moreover, the integration of various renewable energy sources or the fusion of renewable energy with conventional power sources gives rise to hybrid systems. This strategy effectively broadens the range of energy sources utilized and reduces the impact of intermittent energy supply. Furthermore, the integration of smart grid technologies facilitates enhanced control and allocation of electrical power resources. These systems possess the potential to effectively manage the equilibrium between supply and demand by dynamically adjusting to variations in the availability of renewable energy sources. BESs have garnered considerable interest in recent years as a developing technology capable of mitigating a range of environmental issues. This technology possesses the capacity to fundamentally transform how we react to environmental concerns, encompassing waste management, energy generation, resource retrieval, and pollution mitigation. Within the domain of wastewater treatment, BESs assume a pivotal and transformational function. Conventional treatment methodologies frequently entail substantial energy use, as such BESs provide a viable and sustainable solution by utilizing the energy generated through microbial metabolisms to facilitate electrochemical reactions, hence promoting energy efficiency and cost-effectiveness in the treatment of wastewater. BESs play a significant role in the retrieval of valuable resources from waste streams. Through the utilization of the metabolic processes of microbes, BESs facilitate the harnessing of energy in the form of electricity, as well as the conversion of organic substances into valuable outputs like methane or hydrogen. This is consistent with the ideas of a circular economy, wherein waste is transformed into a valuable resource. In the global pursuit of carbon emissions reduction, BESs present a viable and sustainable pathway. They enable the processing of organic waste while minimizing dependence on energy sources derived from fossil fuels. The decrease in the carbon footprint holds significant importance within the framework of addressing climate change and transitioning towards more environmentally friendly energy alternatives. BESs also play a significant role in the field of bioremediation by augmenting the process of pollutant breakdown. The microorganisms present in BESs have a high level of efficacy in the degradation of pollutants found in soil or water, hence providing a sustainable and environmentally conscious approach to remediation purposes.