Estimation of shallow geothermal potential to meet building heating demand on a regional scale

Extracting shallow geothermal energy using borehole heat exchangers (BHEs) can help decarbonising theresidential heating sector, particularly where no other low-carbon heating solutions are readily available.To assist urban planners and policy makers in developing carbon-neutral heating plans, the regionaltechnical shallow geothermal potential must be known. Here, we calculate the technical geothermalpotential of BHEfields on a regional scale while taking potential thermal interference between BHEs,geological conditions, as well as space available for BHE installation into account. The number of BHEsplaced is maximized and heat extraction rate from each BHE is optimized taking regional regulations intoaccount. When the methodology is applied to the German state of Baden-Württemberg on a building-block scale, results suggest an annual technical potential of 33.5 TWh. We then link this technicalgeothermal potential to heating demand scenarios on a building block scale and the results show that,depending on the renovation status of the buildings, between 44% and 93% of all building blocks can beheated using only BHEs. This allows for a rapid identification of building blocks for which BHEs are notable to meet the heating demand and where other means of heat supply will be needed

Skin diseases in hospitalized geriatrics:a 9-year analysis from a University Dermatology Center in Germany

The demographic trend of an ageing society is mirrored in the rising number of hospitalized geriatric patients in Germany. However, there is still a wide gap of knowledge regarding the dermatological diseases, comorbidities and performed procedures within this growingly important group of patients. The study was conducted as a retrospective monocentric data analysis of all patients 65 years or older from the Department of Dermatology, Medical Center-University of Freiburg, Germany. In total, 10,009 individual hospitalisations were included from 2009 to 2017, and there was a notable increase of geriatric patients in the study period. This study illustrates the following: leading major diagnoses included malignant neoplasm of the head and neck, ulcerated and non-ulcerated inflammatory spectrum of chronic venous insufficiency, whereas angina pectoris, type 2 diabetes and cardiac diseases were noted most frequently as secondary diagnoses. Patients with venous diseases had considerably more often cardiopulmonary minor diagnoses, whereas endocrine diagnoses peaked in the cohort of patients with psoriasis and psychiatric and muscululoskeletal disorders in patients with bullous dieseases. Moh's surgery, dressings and multimodal dermatological treatments were the most often encoded procedures

Fast calculation of the technical shallow geothermal energy potential of large areas with a steady-state solution of the finite line source

Shallow geothermal energy systems may play a significant role in the energy transition as they can strongly reduce the carbon emissions from the residential heating and cooling sector. For urban and rural planning, policy making, and the development of regulations, regional scale estimations of the heating potential of borehole heat exchangers (BHEs) are required. For such regional estimations of the technical geothermal potential the thermal interference between BHEs is a crucial parameter to take into account as it can strongly reduce the heat extraction rate in borehole fields with a high BHE density. Here, we propose an analytical solution of the steady-state finite line source solution to calculate thermal response factors, or g-functions, within large BHE fields with variable distances between, and lengths of, boreholes. We show that the methodology can be used to rapidly calculate the thermal interference of boreholes on a regional scale and apply it to estimate the technical shallow geothermal potential of the German state of Baden-Württemberg. The results highlight areas where BHEs can offer a good alternative to fossil fuel-based heating options and will be used by municipalities within the study area for the development of local carbon neutral heating plans

Fast calculation of the technical shallow geothermal energy potential of large areas with a steady-state solution of the finite line source

Shallow geothermal energy systems may play a significant role in the energy transition as they can strongly reduce the carbon emissions from the residential heating and cooling sector. For urban and rural planning, policy making, and the development of regulations, regional scale estimations of the heating potential of borehole heat exchangers (BHEs) are required. For such regional estimations of the technical geothermal potential the thermal interference between BHEs is a crucial parameter to take into account as it can strongly reduce the heat extraction rate in borehole fields with a high BHE density. Here, we propose an analytical solution of the steady-state finite line source solution to calculate thermal response factors, or g-functions, within large BHE fields with variable distances between, and lengths of, boreholes. We show that the methodology can be used to rapidly calculate the thermal interference of boreholes on a regional scale and apply it to estimate the technical shallow geothermal potential of the German state of Baden-Württemberg. The results highlight areas where BHEs can offer a good alternative to fossil fuel-based heating options and will be used by municipalities within the study area for the development of local carbon neutral heating plans

Fast calculation of the technical shallow geothermal energy potential of large areas with a steady-state solution of the finite line source

Shallow geothermal energy systems may play a significant role in the energy transition as they can strongly reduce the carbon emissions from the residential heating and cooling sector. For urban and rural planning, policy making, and the development of regulations, regional scale estimations of the heating potential of borehole heat exchangers (BHEs) are required. For such regional estimations of the technical geothermal potential the thermal interference between BHEs is a crucial parameter to take into account as it can strongly reduce the heat extraction rate in borehole fields with a high BHE density. Here, we propose an analytical solution of the steady-state finite line source solution to calculate thermal response factors, or g-functions, within large BHE fields with variable distances between, and lengths of, boreholes. We show that the methodology can be used to rapidly calculate the thermal interference of boreholes on a regional scale and apply it to estimate the technical shallow geothermal potential of the German state of Baden-Württemberg. The results highlight areas where BHEs can offer a good alternative to fossil fuel-based heating options and will be used by municipalities within the study area for the development of local carbon neutral heating plans

Enabling secure subsurface storage in future energy systems: An introduction

Geological structures in the subsurface have been used for the storage of energy and waste products for over a century. Depleted oil and gas fields, saline aquifers or engineered caverns in salt or crystalline rocks are used worldwide to store energy fluids intended to provide demand buffers and sustained energy supply. The transition of our energy system into a clean, renewable-based system will most likely require an expansion of these subsurface storage activities, to host a wide variety of energy products (e.g. natural gas, hydrogen, heat or waste energy products, like CO2) to balance the inherent intermittence of the renewable energy supply. Ensuring the safety and effectiveness of these subsurface storage operations is therefore crucial to achieve the sought-after renewable energy transition while ensuring energy security

Fast calculation of the technical shallow geothermal energy potential of large areas with a steady-state solution of the finite line source

Shallow geothermal energy systems may play a significant role in the energy transition as they can strongly reduce the carbon emissions from the residential heating and cooling sector. For urban and rural planning, policy making, and the development of regulations, regional scale estimations of the heating potential of borehole heat exchangers (BHEs) are required. For such regional estimations of the technical geothermal potential the thermal interference between BHEs is a crucial parameter to take into account as it can strongly reduce the heat extraction rate in borehole fields with a high BHE density. Here, we propose an analytical solution of the steady-state finite line source solution to calculate thermal response factors, or g-functions, within large BHE fields with variable distances between, and lengths of, boreholes. We show that the methodology can be used to rapidly calculate the thermal interference of boreholes on a regional scale and apply it to estimate the technical shallow geothermal potential of the German state of Baden-Württemberg. The results highlight areas where BHEs can offer a good alternative to fossil fuel-based heating options and will be used by municipalities within the study area for the development of local carbon neutral heating plans

High resolution luminescence chronology of coastal dune deposits near Chumphon, Western Gulf of Thailand

The development of coastal dunes is linked to environmental controls such as sea-level variability, climatic conditions, and coastal morphology. Understanding the spatial and temporal variations of dunes is crucial for predicting how coastal landscapes may react to future climate changes and sea-level rise. However, there are very few detailed studies on the longer time-scale evolution (centennial to millennial) of coastal dunes from subtropical and tropical regions. Here, we combine a high-resolution luminescence chronology with sedimentological analyses to study the depositional history of a transverse coastal dune located within the Bang Berd dune field, Western Gulf of Thailand. While luminescence dating of uniform aeolian deposits is normally straight forward, we observe strong variations in the natural dose rate which are likely explained by the enrichment of accessory minerals in some laminae. Deposition of the dune started at least around 3000 years ago and coincides with a regional sea level drop. Sedimentary structures indicate deposition occurring predominantly in relation to the northeasterly winter monsoon. As the sea-level rise and increased storm intensity in the future may lead to stronger erosion along the coast, this study is highlighting the importance of the Bang Berd dune system as natural protection against coastal inundation

Effect of Using Different Chemical Dispersing Agents in Grain Size Analyses of Fluvial Sediments via Laser Diffraction Spectrometry

Laser diffraction spectrometry allows for efficiently obtaining high-resolution grain size data. However, pretreatment and dispersion of aggregates in sediment samples are essential pre-requisites for acquiring accurate results using this method. This study evaluates the effectiveness of five dispersing agents in deflocculating the investigated fluvial sediments and the resulting grain size distribution obtained by laser diffraction spectrometry. We also examine the ability of the different dispersing agents to deflocculate sediment samples treated by thermal combustion. Distilled water presented a low efficiency in deflocculating the samples and yielded a near-zero clay content for samples with an expected clay content. The other chemical dispersants were effective in dispersing aggregates and yielding clay, albeit with different efficiencies. Calgon had the highest dispersing ability, followed closely by sodium tripolyphosphate. The performance of chemical treatment with sodium oxalate approaches that of sodium tripolyphosphate. However, it leads to the formation of precipitates in the samples, obscuring the actual grain size data. Sodium pyrophosphate derived the least amount of deflocculation among the four chemical dispersants. Furthermore, all the chemical dispersants were found to be ineffective in dispersing aggregates in samples treated by thermal combustion