Abstract
Groundwater samples were collected from the tubular wells of a groundwater heat pump (GWHP), and the psychrophilic, mesophilic, and thermophilic bacteria inhabiting the collected groundwater were cultured and isolated. Using the isolated bacteria, we analyzed temperature-dependent changes in autochthonous bacteria based on the operation of the GWHP. Microbial culture identified eight species of bacteria: five species of thermophilic bacteria (Anoxybacillus tepidamans, Bacillus oceanisediminis, Deinococcus geothermalis, Effusibacillus pohliae, and Vulcaniibacterium thermophilum), one species of mesophilic bacteria (Lysobacter mobilis), and two species of psychrophilic bacteria (Paenibacillus elgii and Paenibacillus lautus). The results indicated A. tepidamans as the most dominant thermophilic bacterium in the study area. Notably, the Anoxybacillus genus was previous reported as a microorganism capable of creating deposits that clog above-ground wells and filters at geothermal power plants. Additionally, we found that on-site operation of the GWHP had a greater influence on the activity of thermophilic bacteria than on psychrophilic bacteria among autochthonous bacteria. These findings suggested that study of cultures of thermophilic bacteria might contribute to understanding the bio-clogging phenomena mediated by A. tepidamans in regard to GWHP-related thermal efficiency.
Highlights
Renewable energy is collected from renewable sources, such as sunlight, wind, rain, tides, waves, and geothermal heat [1,2], whereas geothermal energy describes heat derived from the Earth, and represents both clean and sustainable energy
We performed analytical experiments on psychrophilic, mesophilic, and thermophilic bacteria in seasonal groundwater samples collected from a groundwater heat pump (GWHP) system and evaluated temperature-dependent changes in autochthonous bacteria based on GWHP operation
20 μL of InstaGene Matrix was placed in a sterilized isolate and store and a visible polymerase chain thermophilic reaction (PCR) tube, andpsychrophilic/mesophilic a sterilized toothpick was used to bacteria, collect and transfer a
Summary
Renewable energy is collected from renewable sources, such as sunlight, wind, rain, tides, waves, and geothermal heat [1,2], whereas geothermal energy describes heat derived from the Earth, and represents both clean and sustainable energy. The benefits of geothermal energy provided by these systems support market demands, including providing low operating costs, eco-friendliness, and compatibility with building designs Geothermal systems, such as those based on the use of groundwater, reportedly ensure high efficiency as the most stable, eco-friendly, and low-cost options among currently available cooling and heating systems, and have promoted increased related academic research [4,21]. The efficiency of the tubular wells continuously used for long periods decreases upon clogging through the mechanical process associated with erosion of the underwater pump, chemical processes associated with mineral precipitation due to water–rock reactions, and biological processes related to biomass accumulation due to bacterial activity Such phenomena might reduce thermal efficiency and the quantity of water collected by the GWHP, as well as water quality [26,27,28,29,30,31,32]. We performed analytical experiments on psychrophilic, mesophilic, and thermophilic bacteria in seasonal groundwater samples collected from a GWHP system and evaluated temperature-dependent changes in autochthonous bacteria based on GWHP operation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
