Geothermal reservoir heat transfer, temperature modelling and electrical power potential estimation: Gisenyi hot spring

Abstract

As the energy demand is increasing every day, the environmental pollution has been a main concern. To reduce environmental pollution while satisfying the energy demand, renewable energy is a good solution and attracted many researchers not only to produce clean energy but also to find sustainable energy solution. Among renewable energy, geothermal energy is one of promising renewable sources and is recently given a high consideration. The tectonic position of Rwanda and volcanism show that Rwanda may have promising geothermal resources. One of the evidences is the hot springs originated from tectonic. Gisenyi hot spring is located in Northern Province nearest to the Kivu Lac on the base of volcanoes with surface water temperature of 71°C. In this paper, the conceptual and numerical models were made on Gisenyi hot spring based on geological, geochemical, hydrochemistry and geophysical data to estimate the temperature profile of the spring. This paper assesses the reservoir temperature of Gisenyi hot spring by using various geothermometers along with existing data and information using MATLAB software. The electrical power potential using Organic Rankine Cycle and Carbon dioxide as a working fluid have been assessed together with the optimum depth by considering the dominant mode of heat transfer.

Water-rock interaction, formation and circulation mechanism of highly bicarbonate groundwater in the northwestern geothermal prospects of Rwanda

“…The data produce a complete analytical data set which include isotopic and chemical data of thermal, non-thermal and lake waters and in situ measurements of pH, electrical conductivity, and temperature. The Germany Institute for Geosciences and Natural Resources in collaboration with the Icelandic Geo Survey, the Kenya Electricity Generating Company and the Spanish Institute for Technology and renewable Energies conducted the field and laboratory analysis (Rutagarama, 2015;Nshimyumuremyi and Junqi, 2020).…”

“…The rifting is associated with faulting and volcanism in the East African region and the hot springs are found in the northern and western parts of the country. Geothermal energy generation potential is promising due to the country's position within the Great Africa rift valley (Nshimyumuremyi and Junqi, 2020).…”

“…The northern part of Rwanda has an annual average temperature of 25°C, and an annual average atmospheric precipitation of 1362.2 mm that recharges the groundwater of the studied area (Nshimyumuremyi and Junqi, 2020). Therefore, the studied waters samples with the measured temperature greater than 25°C, are herein considered to be thermal waters.…”

Influence of Mineral Deposition on the Retention of Potentially Hazardous Elements in Geothermal Spring Sediments

“…Geothermal springs, which are mainly distributed in areas with active geological and structural activities [1,2], are widely developed for power generation and directly used for bathing by the local residents [3]. However, concerns regarding environmental and health risks have gradually emerged along with the rapid development of geothermal energy [4,5]. Because of the contact with the geological formation overlying the reservoir and the input of volatile matter from the magma, the hot spring water might be polluted by a variety of hazardous and toxic materials [6][7][8][9][10][11][12].…”