High voltage generation from wastewater by microbial fuel cells equipped with a newly designed low voltage booster multiplier (LVBM)

• Published in: Scientific reports Vol. 10; no. 1; p. 18985
• Main Authors: Koffi, N’Dah Joel, Okabe, Satoshi
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 04-11-2020; Nature Publishing Group
• Subjects: 639/166/986; 639/4077/909; Fuel cells; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary); Voltage; Wastewater
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-75916-7

Although microbial fuel cells (MFCs) can produce renewable energy from wastewater, the generated power is practically unusable. To extract usable power from an MFC fed with wastewater, we newly developed a low voltage booster multiplier (LVBM), which is composed of a self-oscillating LVB and multistage voltage multiplier circuits (VMCs). The low output MFC voltage (ca. 0.4 V) was successfully boosted up to 99 ± 2 V, which was the highest voltage that has been ever reported, without voltage reversal by connecting an LVB with 20-stage VMCs. Moreover, the boosted voltage (81 ± 1 V) was stably maintained for > 40 h even after disconnecting the LVBM from the MFC. The energy harvesting efficiency of LVBM was > 80% when an LVB with 4-stage VMCs was charged to 9.3 V. These results clearly suggest that the proposed LVBM system is an efficient and self-starting energy harvester and storage for low-power generating MFCs.