First EAGE Symposium and Exhibition on Geosciences for New Energies in America
- Conference date: December 3-5, 2024
- Location: Mexico City, Mexico
- Published: 03 December 2024
-
-
Feasibility Evaluation of a Hybrid, Deep Geothermal Plant in Remote Northern Areas of Canada
More LessAuthors A. Dehghani-Sanij, A. Wigston, M. Razavi, M.B. Dusseault and R.A. FraserSummaryGeothermal plants, whether stand-alone or hybrid, are clean and sustainable technologies able to provide the stable baseload energy (heat and power) required by remote, rural, or urban areas. This research evaluates the technical and economic feasibility of using a hybrid, deep geothermal plant to supply the power requirements of Fort Liard (FL), an Indigenous, remote and off-grid community in the Northwest Territories (NT), Canada, which heavily relies on fossil fuel. The designed power plant has two deep wells (for extraction and injection of brine), a geothermal one-stage binary cycle system, solar and wind systems, plus a battery bank and a backup diesel facility. The results demonstrate that the hybrid, deep geothermal plant can provide stable baseload power to fulfill FL’s yearly energy requirements over a 30-year lifetime by scheduling to run only the wind and solar systems for six months (April to September) when there are favourable weather conditions and operate the wind, solar, and geothermal systems together for the rest of the year. The cost of energy (COE) for the designed power plant is ∼0.35 CAD$/kWh, while FL’s current diesel-reliant installation, excluding the northern diesel subsidy, incurs a COE of ∼0.70 CAD$/kWh, which is double. The economic evaluation also indicates that the period of return on investment (ROI) for the hybrid, deep geothermal plant is calculated to be ∼18 years.
-
-
-
-
-
-
Electric Resistivity Tomography in 2D and 3D Applied to Characterize Urban Subsoils
More LessAuthors R.E. ChavezSummaryMore than 70% of urban areas seated on the Basin of Mexico were built on what was once Lake of Texcoco, which is mainly made up of clayey sediments. The growth of Mexico City and surrounding areas has increased the supply of drinking water to the inhabitants of this region. Over time, this process of exploitation of the aquifers has caused a differential subsidence in the valley, reaching in some points (towards the N and NE) up to 40 cm/year. If we add to this, the increase in water-extraction wells, leaks in pipe lines, etc., the hydrostatic balance in the subsoil has been modified, which has seriously affected the buildings and houses settled on these clays. This paper presents the effects on urban areas and how geophysical methods, particularly the Electrical Resistivity Tomography method in its 2D and 3D modalities, can characterize the subsoil, in such a way that geological and anthropogenic features that may represent a risk for urban infrastructure on the surface can be recognized. Some examples are presented where the Exploration Group has worked on: location of cavities, detection of fracture patterns, subsidence, among others.
-
-
-
A Review of Geophysical Methods used for Near Surface Exploration in Seismic Microzonation Studies and their Application
More LessAuthors M. SchmitzSummarySeismic microzonation studies are an essential tool for the mitigation of seismic risk, especially in developing countries with rapidly increasing population moving to big urban areas with increasing earthquake risk. Besides regional seismic hazard due to proximity to active faults, local soil conditions are a first order feature that controls shaking. Urban planning and development that considers local soil conditions helps preventing building damage and loss of lives. Geophysical investigations, coordinated with geological observations and geotechnical studies, are a key for addressing the subsoil configuration. The application of the different geophysical methods depends strongly on the geological characteristics and addresses the shape and depth of sedimentary basins and quality of the uppermost layer (Vs30) regarding shaking amplification and induced effects as soil liquefaction and landslide hazard. Due to restricted space and city regulations, methods based on ambient noise recently take the lead over traditional geophysical methods, as they are cost-effective and environmentally friendly. Basin shape and depth can effectively be addressed with a combination of gravimetric surveys (for basin geometry) and seismic noise measurements (for the generation of 1-D shear wave soil profiles) from individual measurements for determination of fundamental soil periods to array measurements. In both cases, depending on the record time, inversion of Rayleigh wave dispersion and ellipticity curves allows to derive 1-D profiles down to the seismic basement. For near surface exploration, passive methods have widely replaced seismic acquisition with active sources as sledgehammer or explosives. Acquisition geometry and logistics is similar to active methods with standard 48 channel seismographs, but a wide variety of processing options are available as ReMi (Refraction Microtremor), MASW and iMASW (interferometric Multi-channel Analysis of Surface Waves). Density of measurement grid depends strongly on geological conditions and urban dimensions but should not exceed 300-500 m. Data might be completed with available geotechnical information or specially designed geotechnical drillings.
-