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[en] The paper conducts comparative analyzes of the advantages and disadvantages of existing and currently used in the countries of the world, including Azerbaijan, domestic energy sources, and also indicates the environmental and economic advantages of using, in future energy, alternative and renewable energy sources (ARES). For this purpose, a special analysis method is used. The results are presented in tabular form.
[en] Alsace possesses the most powerful hot water springs in France at accessible depths. This article presents the activities of the Fonroche Geothermie company which started the first project of deep geothermal energy near Strasbourg, more precisely on the site of the Vendenheim Rhine eco-park. The budget and financing actors are indicated. The techniques and works are described. Water at 200 degrees Celsius has been reached at a depth of 4600 meters. Exploitation is expected to start in 2020. Some future projects are mentioned in the same region and in others as well. Objectives in terms of price are discussed, and the interest of foreign actors is mentioned
[en] This preliminary study investigated data mining-based methods to assess and predict the performance of geothermal heat pump(GHP) system. Data mining is a key process of the knowledge discovery in database (KDD), which includes five steps: 1) Selection; 2) Pre-processing; 3) Transformation; 4) Analysis(data mining); and 5) Interpretation/Evaluation. We used two analysis models, categorical and numerical decision tree models to ascertain the patterns of performance(COP) and electrical consumption of the GHP system. Prior to applying the decision tree models, we statistically analyzed measurement database to determine the effect of sampling intervals on the system performance. Analysis results showed that 10-min sampling data for the performance analysis had highest accuracy of 97.7% over the actual dataset of the GHP system.
[en] After having outlined that geothermal energy encompasses a large range of heat, this study first addresses the case of Very Low Energy geothermal energy, i.e. from 10 to 30 C: methodology of a survey on geothermal drilling, sales of geothermal heat pumps, assessment of the very low energy geothermal market in 2015, perspectives of development. The next part addresses the low energy geothermal energy (between 30 and 90 C): operations and usages, level of French production in 2015 (cases of the Parisian basin and of the Aquitaine basin, and other exploited sources: Rhone corridor and Limagne). The high geothermal energy (beyond 90 C) is then addressed: operations and usages, operated high geothermal energy plants in France, project planning in France). The next part outlines that the sector is always more structured (support arrangements, certified professionals). Geothermal energy is finally presented as an asset for energy transition.
[en] Highlights: • A numerical model of reaction for thermal spallation drilling is proposed. • The reliability of the numerical model is validated in experiment. • Characteristics of reaction flow field are investigated. • Effects of dimensions of the reactor on the flow field are studied. - Abstract: Thermal spallation technology is an alternative drilling method, which has the potential to exploit petroleum and geothermal energy with low costs. In this paper, the influence of the structure of the reactor on the characteristics of the flame jet is analyzed from aspects of outlet velocity, temperature, pressure and mole fraction. The Peng-Robinson equations of state and eddy dissipation model are applied in the simulation. An experimental setup is designed and experiments are performed to validate the simulation results. Results show that the reactor length and nozzle length can be reduced in a proper range to obtain better results. The suitable nozzle diameter may be changed for different types of rock to obtain the best rate of penetration. Also, no cooling water may be injected until the temperature of the reactor wall reaches the limitation of failure. Results could provide guidance for field applications.
[en] Geothermal energy is one of the important renewable energy resources. Understanding the nature of geothermal systems for the sustainable exploitation is important and isotope hydrology is one of the tools for the same. The isotopic content (δ18O, 3H, 222Rn etc.) of geothermal water provides information about their recharge sources, flow path and interactions with magmatic water. The aim of the paper is to identify the sources of geothermal water and their mixing processes
[en] An alkali-activated blend of aluminum cement and class F fly ash is an attractive solution for geothermal wells where cement is exposed to significant thermal shocks and aggressive environments. Set-control additives enable the safe cement placement in a well but may compromise its mechanical properties. Here, this work evaluates the effect of a tartaric-acid set retarder on phase composition, microstructure, and strength development of a sodium-metasilicate-activated calcium aluminate/fly ash class F blend after curing at 85 °C, 200 °C or 300 °C. The hardened materials were characterized with X-ray diffraction, thermogravimetric analysis, X-ray computed tomography, and combined scanning electron microscopy/energy-dispersive X-ray spectroscopy and tested for mechanical strength. With increasing temperature, a higher number of phase transitions in non-retarded specimens was found as a result of fast cement hydration. The differences in the phase compositions were also attributed to tartaric acid interactions with metal ions released by the blend in retarded samples. The retarded samples showed higher total porosity but reduced percentage of large pores (above 500 µm) and greater compressive strength after 300 °C curing. Lastly, mechanical properties of the set cements were not compromised by the retarder.
[en] After a presentation of the AFPG (French Association of Geothermal Professionals) missions and actions, of the assets of geothermal energy, and of the situation of the sector, this document gathers contributions under the form of Power Point presentations. The addressed topics and issues have been: the different forms of geothermal energy, the analysis of a regional context (New Aquitaine), the regulation regarding geothermal energy of minor importance, the technical and technological aspects of the different forms of capturing the geothermal resource, the determination of the right equipment type (heat pump) and sizing for a building, the issue of a regulation of a geothermal installation, the main steps of heat-pump-assisted geothermal project, aids, tools actors to support a successful project.
[en] The energy demand estimation commands great importance for both developing and developed countries in terms of the economy and country resources. In this study, the differential evolution algorithm (DE) was used to forecast the long-term energy demand in Turkey. In addition to being employed for solving regular optimization problems, DE is also a global, meta-heuristic algorithm that enables fast, reliable and operative stochastic searches based on population. Considering the correlation between the increase in certain economic indicators in Turkey and the increase of energy consumption, two equations were used-one applying the linear form and the other the quadratic form. Turkey's long-term energy demand from 2012 to 2031 was estimated through the DE method in three different scenarios and in terms of the gross domestic product, import, export and population. To prove the success of the DE method in addressing the energy demand problem, the DE method was compared to other methods found in the literature. Results showed that the proposed DE method was more successful than the other methods. Furthermore, the future projections of energy demand obtained using the proposed method were compared to the indicators of energy demand estimated and observed by the Ministry of Energy and Natural Resources. (author)