Industrialization and technological advancements have resulted in unprecedented anthropogenic carbon dioxide (CO2) emissions, inducing climate change and carbon imbalances. In this context, volatile fatty acids produced traditionally through petrochemical processes are energy-intensive and have a negative impact on the environment. Valorizing CO2 in bioelectrochemical systems can be a sustainable alternative, where the metabolism of exoelectrogenic microbes controls the fermentation, channeling the production of biofuels and industrial precursors. Besides the dark fermentation of organic waste that produces hydrogen gas (H2) along with the industrial precursors, CO2 is often considered an auxiliary byproduct. This untapped CO2 is of considerable magnitude and it is a potential greenhouse gas. Therefore, sequestering or utilizing it in electro-fermentation processes can assist in producing an integrated and viable solution for delivering these bio-based products. Hence, the current chapter delves into the principal mechanisms and potential application of dark fermentation and electro-fermentation aiming at waste valorization. It also emphasizes the possible integrated solution to handle this organic waste fraction and simultaneously reduce CO2 to platform chemicals and biofuels.