The recent energy crisis has reinvigorated interest in a technology using microbial electric systems (MES) that can generate energy without a net carbon dioxide emission. MES converts the energy stored in chemical bonds in organic compounds to electrical energy through the catalytic reactions of microorganisms. MES hold significant promise for the sustainable remediation of chlorinated solvents, such as tetrachloroethene (PCE) as bacteria can be used to generate bioenergy while accomplishing the biodegradation of toxic contaminants. Although the bio-electrochemical potential of some specific bacterial species such as Dehalococcoides, Geobacteraceae have been exploited, this ability in other undefined microorganisms has not been extensively assessed. Hence, this study investigated indigenous and potentially electrochemical active microorganisms in PCE contaminated groundwater collected from PCE contaminated site in Victoria, Australia. Lab-scale MES were fed with acetate/H₂ and electrode/PCE as electron donors and acceptors under biostimulation (BS) and biostimulation-bioaugmentation (BS-BA) regimes. Molecular analysis of the indigenous groundwater community represented mainly Spirochaetes, Firmicutes, Bacteroidetes, γ and δ-Proteobacteria. Environmental scanning electron photomicrographs of the anode surfaces showed extensive indigenous microbial colonization under both regimes. This colonization and biostimulation resulted in 100% dechlorination in BS and BS-BA samples with complete dechlorination occurring 4 weeks earlier in BS-BA samples and up to 11.5 µA of current being generated. However, the indigenous non-Dehalococcoides community was found to contribute significantly to electron transfer with 61% of the current generated due to their activities. This study therefore shows the potential of indigenous non-Dehalococcoides bacterial community in bio-electrochemically reducing PCE which could enhance MES efficiency. Overall, based on these results a clear understanding of microbial ecology involved in energy conservation during PCE degradation via electron transfer mechanism will assist to advance this field in a rational manner.