Application of Benthic Microbial Fuel Cells in Systems of Year-Round Monitoring of Water Environment Parameters

The bioelectrogenic activity of sediments of natural microbial association of the Peter’s Bay of Japanese sea research was performed in a year-round experiment with parallel temperature, illumination and water electrical conductivity monitoring by means of benthic microbial fuel cell (MFC) and automatic online-monitoring. Several variants of underwater devices, including benthic microbial fuel cells, monitoring water environment sensor,information collection and transmission systems, have been developed. This device make electrical voltage up to 216 mV, specific power up to 239 mW/m². Electrogenic activity of natural microflora depends on water temperature and reach maximum on summer with temperature about 20–25°C. The introduction of toxicants in form as hydrocarbons and cadmium into the sluge led to the suppression of microbial electrogenesis. However the introduction of inductor substances of microbial sulfidogenesis led to the stimulation of microbial electrogenesis. The possibility of functioning of the benthic MFC in the field of the Peter’s Great Bay in various climatic periods is shown. It is shown that such experimental devices serve as a basis for autonomous stations monitoring the state of the aquatic environment for a long time and in a wide range of conditions change. Thus, automatic registration of temperature, illumination and salinity of water with a frequency of 48 times a day was carried out for 13 months (11/28/2019–12/31/2020). The electrogenic activity of this microbiota upon MFC scaling can potentially become a new renewable energy source for low-power marine electronics, including those used in mariculture.