Volcano-tectonic events in Libungo can be the cause of the presence of geothermal potential. There is no detailed research on shallow subsurface conditions in Libungo that can show the distribution of subsurface fluids. This research aims to create a shallow subsurface model of the Libungo geothermal area based on resistivity data. Resistivity data collection was carried out in the Libungo hot springs area. The electrode configuration used is the Schlumberger configuration. The variation in resistivity values is calculated using current data, potential difference data and geometry factors. The results of the calculation of the resistivity values variation are plotted versus depth. Variations of resistivity value versus depth are then displayed in the form of a single log, lithology distribution and 3D lithology model. The results showed that the shallow subsurface of the Libungo geothermal area was composed of andesite, volcanic breccia, silty clay and clay. Andesite in the research area has resistivity values ranging from 320 - 349 Ωm, has slightly fracture and is andesite dry. Volcanic breccia has a resistivity value of 177-198 Ωm, has a well to slightly fracture and is a volcanic breccia moist. Silty clay has a resistivity value of 3.25-37.99 Ωm and is a wet to moist silty clay. Clay has resistivity values in the range 1.56-2.78 Ωm and is wet to moist clay. Fluid distribution in the shallow subsurface area occurs in volcanic breccia, silty clay and clay. Shallow subsurface fluids accumulate mostly in the northern part of the Libungo geothermal area.

Gorontalo is located at the macro and micro plate boundary, therefore it is located in an active seismotectonic region. This study aims to analyze earthquake damage level in Gorontalo based on seismicity and peak ground acceleration. The data used is obtained from the USGS. Data is made into a database and plotted onto a geological map. Calculation of peak ground acceleration is obtained using the Kawashumi formula. The results of this study indicate that Gorontalo is included in the slight to moderate earthquake damage level because it is dominated by shallow to intermediate earthquake's depth, light to moderate earthquake magnitude, and have a peak ground acceleration 1,462-99,714 gal.

Bongongoayu is one of the regions in Indonesia that has geothermal potential. Bongongoayu requires surface and subsurface data to support the preliminary data. This research aims to determine surface and subsurface data conducted by geology and magnetic method. The surface data, including geomorphology, lithology, hydrology and manifestation. The subsurface data have taken by the magnetic method. The result showed that the geothermal manifestation of Bongongoayu is a hot pool. The surface temperature is 43 to 59 °C. The geomorphology units is composed of volcanic hills unit and lake plains unit. The lithology of the research area is composed of granite and alluvial deposits. Based on petrographic analysis, the level of alteration in granite rocks is 65% and is classified as moderate alteration. The recharge area is in the north and southwest of the research area. Discharge area is in the central area. Based on 2D magnetic modeling, there are two subsurface layers. The first layer is alluvial and the second layer is granite. Rocks that are under the alluvial layer and have been altered are interpreted as a cap rock. 2D magnetic models show normal faults in the research area as a controlling factor for geothermal fluid.

The Gorontalo fault zone is an active fault that crosses Gorontalo Province with a movement of about 11 mm/year. The existence of this fault zone affects the morphological lineaments and offsets along its path and increases the potential of geological disaster hazards. The Olele area is located in the Gorontalo fault zone that makes it potential to landslide disaster. This study aims to analyze the lineaments of the Olele area and its surroundings. The results of this analysis will help to determine the geological structures distribution pattern that develops in the study area and its impact on the mitigation of landslide disasters in the study area. This study uses a spatial analysis method using Digital Elevation Model (DEM) image to analyze slope and lineaments data in the study area. The results of the analysis will be correlated with regional geological structures and give recommendations for geological disaster mitigation that can be implemented. The results showed that the slope class in the study area was dominated by the range of 16-35° and even in several places with a slope of 35-55°. The results of the extraction and processing of lineaments data get 203 data. The lineaments direction is relatively NNW - SSE. This direction indicates that mostly the morphologies are influenced by the existence of the Gorontalo fault zone. The existence of the Gorontalo fault zone makes this area prone to landslide disasters in the case of Gorontalo fault movement. Some prevention recommendations are to increase the slope stability level.

Kabupaten Bone Bolango merupakan daerah yang mulai berkembang sehingga dibutuhkan pasokan energi listrik seperti energi panas bumi untuk menunjang perkembangan. Tujuan dari penelitian ini adalah untuk mengkaji kondisi geologi daerah panas bumi Lombongo. Lokasi penelitian terletak pada koordinat 0°32' LU-0°32'40" LU dan 123°10'40" BT-123°11'40" BT. Kajian dilakukan terhadap manifestasi panas bumi, litologi, morfologi, flow net, dan hidrogeologi daerah penelitian. Pengamatan manifestasi panas bumi berupa sifat fisik air panas dan sifat kimia air panas. Pengamatan litologi dan morfologi meliputi pengamatan mineral dan bentuklahan. Pengamatan hidrogeologi berupa flow net, daerah recharge, daerah discharge, dan daerah limpasan permukaan. Manifestasi panas bumi yang ada di daerah Lombongo berupa mata air panas dengan suhu terukur di lapangan 42 0 C-48 0 C. Pemunculan mata air panas di daerah Lombongo di kontrol oleh sesar mendatar yang melewati batuan tersebut. Litologi daerah Lombongo dan sekitarnya terdiri dari batuan vulkanik berupa andesit dan batuan intrusif berupa diorit. Geomorfologi daerah Lombongo dan sekitarnya terdiri dari Satuan Pegunungan Vulkanik, Satuan Perbukitan Denudasional dan Satuan Dataran Fluvial. Daerah rechange berada pada pegunungan yang ada di bagian utara daerah penelitian sedangkan daerah discharge berada di bagian selatan daerah penelitian. Kajian geologi daerah penelitian menunjukkan bahwa sumber panas berasal dari sisa panas tubuh vulkanik yang memanaskan air tanah di reservoar dan keluar ke permukaan melalui sesar mendatar.

<p><em>The development of photovoltaic thermal (PVT) system is a very promising area of research. PVT systems using in various applications, such as solar drying, solar cooling, water heating, desalination, and pool heating. With the recognition of the potentials and contributions of PV system, considerable research has been conducted to attain the most advancement which may produce reliable and sustainable PVT system. The cooling system’s design refers to the absorber design which mostly focuses on water and air-based PVT systems. An air-based system has been developed through different absorber configurations, air flow modes and single- or double-pass design.</em><em> Hence, a summarization on various research and development of air-based PVT system will be presented.</em></p>

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Renewable energy had been monopolized the research area in these past decade up till nowadays, due to its reliability and future in global production of electrical and thermal energy. Narrowing down the scope to the photovoltaic thermal (PVT) system, lots of improvements had been implied both theoretically and experimentally. One of the most attractive applications of PVT water or air-based collectors is building integrated photovoltaic thermal (BIPVT) system, which has undergone rapid developments in recent years. This review paper comprises the research findings on the improvements that had been integrated by PVT systems as well as well as personal and cited remarks on advancements on cooling techniques on PVT system.