An assessment of the thermal resource in the Straits of Florida was performed to estimate the Ocean Thermal Energy Conversion (OTEC) potential. Direct measurements of the temperature profile across the Florida Straits were taken from nearshore Southeast Florida to the Exclusive Economic Zone boundary along four evenly spaced transects perpendicular to Florida's Southeast coast, spanning 160 km. Along the southern transects in summer, nearshore cold and warm water resources meet or exceed the average 20ÀC temperature difference required for OTEC. In winter, the nearshore average DT of 17.76ÀC can produce 59-75% design net power and 70-86% in spring with DT averaging 18.25ÀC. Offshore along the southern transects, a high steady DT from 18.5- 24ÀC creates an annual average net power of 120-125MW. Along the northern transects, the nearshore resource does not exist, but a consistent OTEC resource is present offshore, providing 70-80% design net power in winter, and 100-158% in spring and summer. / by Anna E. Leland. / Thesis (M.S.C.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

The following study explores the worldwide spatial and temporal distributions of electrical power that can be extracted from the ocean's stored solar energy via the process of closed-cycle ocean thermal energy conversion (OTEC). Special emphasis is placed on resources surrounding the state of Florida. The study combines oceanographic input from a state-of-the-art ocean circulation model, the Hybrid Coordinate Ocean Model, with a state-of-the-industry OTEC plant model to predict achievable power values across the world. These power predictions are then constrained by local replenishment rates of cold deep sea water to provide an upper limit to the sustainable OTEC resource. Next, the geographic feasibility of OTEC-coupled and OTEC-independent sea water cooling (air conditioning and refrigeration) are explored. Finally, the model data is validated against in situ oceanic measurements to ensure the quality of the predictions. / by Lynn Rauchenstein. / Thesis (M.S.C.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

An Enhanced Geothermal System (EGS) allows for the generation of electricity using the Earth's heat by improving ('enhancing') the fracture permeability of rock and flowing fluid through the optimized medium. The complex behavior of EGS fracture systems and heat flow processes are being studied at various scales to determine the practical capabilities of EGS technology. The EGS collaborative (Collab) project is focused on experimentation of intermediate-scale (i.e., 10's of meters) EGS reservoir generation processes and model validation at crystalline rock sites. A key phase of the project involves seismic characterization of a rock mass intended to be representative of EGS reservoir rock. A suite of boreholes was drilled from inside a mine drift on the 4850-foot (~1.5 km) level of the Sanford Underground Research Facility (SURF) in Lead, South Dakota. The boreholes, comprised of one stimulation (injection) well, one production (extraction) well, and six monitoring wells, were each nominally drilled approximately 200 feet (~60 meters) deep into the surrounding crystalline rock formation near the location of a previous experiment at this site (kISMET). Active source seismic data were collected using an electrical sparker source and an electro-mechanical impulse source to generate compressional (P-) wave and shear (S-) wave energy, respectively, at varying depths in the stimulation well. Seismic receivers were deployed in the sub-parallel production well, in addition to receivers installed in the monitoring wells, to detect P- and S-wave arrivals. Over the summer, I picked all the P-wave arrivals and helped generate initial tomographic models. The 3D P- and S-wave velocity models associated with these are presented here with a discussion of the elastic parameters they imply. The rock is found to be more complicated and heterogeneous than expected. Velocity and calculated elastic moduli values are reasonable for crystalline rock. These elastic parameters are used for modeling and monitoring seismic hypocenters that are associated with fracture propagation during EGS stimulation activities.

Ziel dieser Arbeit war es, die Auswirkungen der geothermischen Energieerzeugung aus umwelt- und naturschutzfachlicher Sicht zu untersuchen und zu bewerten. Auf der Grundlage einer umfassenden Literaturstudie, von Expertenbefragungen sowie der Besichtigung des Hydrothermalen Erdwärmekraftwerkes in Neustadt-Glewe und der Erdwärmesondenanlage auf dem Max-Planck-Campus in Golm wurden die für eine behördliche Genehmigung der Erschließung und Nutzung von Erdwärmevorkommen notwendigen gesetzlichen Regelungen systematisch aufgearbeitet und die mit den Techniken zur Erschließung bzw. den Anlagen zur Nutzung von Erdwärme verbundenen umweltrelevanten Wirkfaktoren ausgewiesen und systematisch dargestellt.<br /> Darauf aufbauend wurden die potenziellen Wirkungen auf die Schutzgüter des UVPG qualitativ erfasst und, soweit es in Anbetracht des derzeitigen Standes der Forschung möglich war, quantifiziert. Die Wirkungen wurden schließlich hinsichtlich ihrer Bedeutung und Erheblichkeit im Rahmen von behördlichen Genehmigungsentscheidungen bewertet und miteinander verglichen. Die Anforderungen an den Inhalt von Antragsunterlagen wurden dargestellt.<br><br> Gutachter / Betreuer: Dr. Holger Rößling ; Dipl.-Biol. Karl Scheurlen

This study presents an investigation of the concept of harvesting geothermal energy that remains in heavy oil reservoirs after abandonment when steamflooding is no longer economics. Substantial heat that has accumulated within reservoir rock and its vicinity can be extracted by circulating water relatively colder than reservoir temperature. We use compositional reservoir simulation coupled with a semianalytical equation of the wellbore heat loss approximation to estimate surface heat recovery. Additionally, sensitivity analyses provide understanding of the effect of various parameters on heat recovery in the artificial geothermal resources. Using the current state-of-art technology, the cumulative electrical power generated from heat recovered is about 246 MWhr accounting for 90percent downtime. Characteristics of heat storage within the reservoir rock were identified. The factors with the largest impact on the energy recovery during the water injection phase are the duration of the steamflood (which dictates the amount of heat accumulated in the reservoir) and the original reservoir energy in place. Outlet reservoir-fluid temperatures are used to approximate heat loss along the wellbore and estimate surface fluid temperature using the semianalytical approaches. For the injection well with insulation, results indicate that differences in fluid temperature between surface and bottomhole are negligible. However, for the conventional production well, heat loss is estimated around 13 percent resulting in the average surface temperature of 72 degrees C. Producing heat can be used in two applications: direct uses and electricity generation. For the electricity generation application that is used in the economic consideration, the net electrical power generated by this arrival fluid temperature is approximately 3 kW per one producing pattern using Ener-G-Rotors.

Im Freistaat Sachsen werden 7.500 Gebäude mit Erdwärme klimatisiert. Genutzt wird die Wärme aus der Tiefe vor allem bei Ein- und Mehrfamilienhäusern zur Heizung und Warmwasserbereitung. Bei Planung und Bau von Erdwärmeanlagen sind Aspekte der Qualitätssicherung und rechtliche Vorgaben zu beachten. Interessierten Bürgern, Planern und Bohrfirmen werden u. a. folgende Fragen beantwortet: - Welche Nutzungsformen der Erdwärme gibt es? - Welche Qualitätsanforderungen, Richtlinien und Gesetze sind einzuhalten? - Wie wird eine Anlage richtig geplant? - Wo und wie werden Bohrungen bei Behörden beantragt? Die Informationsbroschüre erscheint in 3. Auflage und ersetzt den Leitfaden für Erdwärmesonden.

Η γεωθερμική ενέργεια είναι μία ήπια, εναλλακτική και ανανεώσιμη πηγή ενέργειας. Η παρούσα εργασία έχει ως αντικείμενο μελέτης τα δύο από τα πέντε γεωθερμικά πεδία του Νομού Ξάνθης, αυτά της Νέας Κεσσάνης και του Νέου Ερασμίου-Μαγγάνων. Στόχος της εργασίας είναι να χαρακτηριστούν τα γεωθερμικά πεδία αυτά και να προταθούν πιθανοί τρόποι αξιοποίησής τους. / Geothermal energy is a clean and renewable source of energy. This project has to do with two out of five geothermal fields of Xanthi, those of Nea Kessani and Neo Erasmio-Maggana. The purpose of this project is for those geothermal fields to be characterized and to propose possible ways to be exploited.

In drei Gebieten Sachsens wurde durch einen Forschungsverbund unter Leitung des LfULG die Nutzung der petrothermalen Geothermie zur Strom- und Wärmegewinnung untersucht. In der Elbezone im Raum Dresden, in Freiberg und Aue-Schneeberg wurden geologische, petrophysikalische und thermische Daten aufgearbeitet und dreidimensionale Modelle bewertet. Die Ergebnisse zeigen, dass eine Stromerzeugung durch Tiefenaufschlüsse bis 5 km Tiefe in allen drei Untersuchungsgebieten möglich ist. Die Temperaturmodelle weisen in 5 km Tiefe Werte zwischen 105 und 190 °C auf. Dabei verfügt das Untersuchungsgebiet Aue-Schneeberg über die besten Voraussetzungen für die Errichtung eines Geothermiekraftwerkes.

Shallow geothermal energy (SGE) systems are becoming increasingly popular due to both their environmental and economic value. By using the ground as a source and sink for thermal energy, SGE systems are able to more efficiently heat and cool structures. However, their utility beyond structural heating and cooling is being realized as their applications now extend to slab and pavement heating, grain and agricultural drying, and swimming pool temperature control. Relatively recently, SGE systems have been combined with deep foundations to create a dual purpose element that can provide both structural support as well as thermal energy exchange with the subsurface. These thermo-active foundations provide the benefits of SGE systems without the additional installation costs. One of the novel applications of thermo-active foundations is in bridge deck deicing. Bridge decks experience two main winter weather related problems. The first of which is preferential icing, where the bridge freezes before the adjacent roadway because the bridge undergoes hastened energy loss due to its exposed nature. The second problem is the accelerated deterioration of concrete bridge decks resulting from the application of salts and other chemicals that are used to prevent accumulation and/or melt the frozen precipitation on roads and bridges. By utilizing the foundation of a bridge as a mechanism by which to access the shallow geothermal energy of the subsurface, energy can be supplied to the deck during the winter to melt and/or prevent frozen precipitation. An experimental ground-source bridge deck deicing system was constructed and the performance is discussed. Numerical models simulating the bridge deck and subsurface system components were also created and validated using the results from the numerical tests. Furthermore, the observed loads that result in a foundation from bridge deck deicing tests are shown. In order to better design for these loads, tools were developed that can predict the temperature change in the subsurface and foundation components during operation. Mechanisms by which to improve the efficiency of these systems without increasing the size of the borehole field were explored. Ultimately this research shows that SGE can effectively be used for bridge deck deicing. / Ph. D.

Mr Wayne Tobeck, Director of Southrim Group (SRG), sponsored this 2013 MEM Project titled; A Technical and Economic Feasibility Study for the Integration of GSHP Technology in the Christchurch Rebuild. Following the recent Christchurch earthquakes, a significant amount of land has become too unstable to support traditional building foundations. This creates an opportunity to implement new and unique foundation designs previously unconsidered due to high costs compared to traditional methods. One such design proposes that an Injection Micro-Piling technique could be used. This can also be coupled with HVAC technology to create a Ground Source Heat Pump (GSHP) arrangement in both new buildings and as retrofits for building requiring foundation repair. The purpose of this study was to complete a feasibility study on the merits of SRG pursuing this proposed product. A significant market for such a product was found to exist, while the product was also found to be technically and legally feasible. However, the proposed product was found to not be economically feasible with respect to Air Source Heat Pumps due to the significantly higher capital and installation costs required. Further analysis suggests GSHPs may become more economically attractive in operating temperatures lower than -9oC, though the existence of markets with this climate in NZ has not been studied. It is therefore suggested that SRG do not proceed with plans to develop a GSHP coupled foundation solution for the Christchurch rebuild.