Search

Based on the World Bank’s own extensive global experience and drawing upon international expertise from leading specialists and practitioners, this report presents a comparative assessment of various approaches that have been applied around the world, with varying degrees of success, to mitigate resource risks and catalyze investments in developing the geothermal sector. It provides a framework that can help decision makers identify suitable approaches that are commensurate with development goals, funding capacity, implementation capabilities, and other circumstances specific to the context in a given country. Geothermal presents an opportunity for many countries to diversify their power generation mix in a sustainable way since it is an environmentally friendly, clean energy source that can reliably produce baseload power on a 24 by 7 basis. Despite over 100 years of development and an estimated global potential of 70 - 80 gigawatts (GW), only about 15 percent of the known geothermal reserves are presently exploited and producing electricity. While there are many reasons, in various countries, for the slow pace of geothermal development, one widely recognized and unique obstacle that is applicable worldwide is the high resource risk during the early stages of the geothermal development process. As a result, it is difficult to mobilize the early-stage investments, especially through the private sector.

The Principal Cordillera of Central Chile is characterized by two belts of different ages and lithologies: (i) an eastern Mesozoic belt, consisting of limestone- and gypsum-rich sedimentary rocks at the border between Central Chile and Argentina, where the active volcanic arc occurs; and (ii) a western belt of Cenozoic age containing basaltic to andesitic volcanic and volcanoclastic sequences. This distinctive geological setting controls water chemistry of cold and thermal springs in the region, which are fed by meteoric water that circulates through deep regional structures. In the western sector of Principal Cordillera, water–rock interaction processes produce low TDS, slightly alkaline HCO3− dominated waters, although dissolution of underlying Mesozoic evaporitic rocks occasionally causes SO42 − and Cl− enrichments. In this area, few Na+–HCO3− and Na+–SO42 − waters occurred, being likely produced by a Ca2 +–Na+ exchange during water–rock interactions. Differently, the chemical features of Ca2 +–Cl− waters was likely related to an albitization–chloritization process affecting basaltic to andesitic rocks outcropping in this area. Addition of Na+–Cl− brines uprising from the eastern sector through the west-verging thrust faults cannot be excluded, as suggested by the occurrence of mantle He (~ 19%) in dissolved gases. In contrast, in the eastern sector of the study region, mainly characterized by the occurrence of evaporitic sequences and relatively high heat flow, mature Na+–Cl− waters were recognized, the latter being likely related to promising geothermal reservoirs, as supported by the chemical composition of the associated bubbling and fumarolic gases. Their relatively low 3He/4He ratios (up to 3.9 Ra) measured in the fumaroles on this area evidenced a significant crustal contamination by radiogenic 4He. The latter was likely due to (i) degassing from 4He-rich magma batches residing in the crust, and/or (ii) addition of fluids interacting with sedimentary rocks. This interpretation is consistent with the measured δ13C-CO2 values (from − 13.2 to − 5.72‰ vs. V-PDB) and the CO2/3He ratios (up to 14.6 × 1010), which suggest that CO2 mostly originates from the limestone-rich basement and recycling of subducted sediments, with an important addition of sedimentary (organic-derived) carbon, whereas mantle degassing contributes at a minor extent. According to geothermometric estimations based on the Na+, K+, Mg2 + and Ca2 + contents, the mature Na+–Cl− rich waters approached a chemical equilibrium with calcite, dolomite, anhydrite, fluorite, albite, K-feldspar and Ca- and Mg-saponites at a broad range of temperatures (up to ~ 300 °C) In the associated gas phase, equilibria of chemical reactions characterized by slow kinetics (e.g. sabatier reaction) suggested significant contributions from hot and oxidizing magmatic gases. This hypothesis is consistent with the δ13C-CO2, Rc/Ra, CO2/3He values of the fumarolic gases. Accordingly, the isotopic signatures of the fumarolic steam is similar to that of fluids discharged from the summit craters of the two active volcanoes in the study area (Tupungatito and Planchon–Peteroa). These results encourage the development of further geochemical and geophysical surveys aimed to provide an exhaustive evaluation of the geothermal potential of these volcanic–hydrothermal systems.

These guidelines are directed to the economic analysis of power sector policy analysis and the appraisal of power sector investment projects. The general guidance is complemented by an Annex Volume that contains relevant technical notes, a glossary, and an extended Bibliography. In this first edition, the focus of the technical notes is on grid-connected renewable energy projects. In FY16 the scope of the technical notes will be extended to cover transmission & distribution, rural electrification, off-grid, energy efficiency, and thermal projects.

This issue of Handshake, focused on public-private partnerships in the power sector, brings diverse expert voices together to discuss how to increase access to energy in developing countries. Features on hydropower and renewables together with examples from Africa and Latin America provide an up-to-the-minute look at one of the most important and rapidly evolving sectors today. This issue includes the following headings: power and mining: digging deep to power up; market mover: intraday electricity trading; timeline to transformation: Nigerias privatization; energy for development: Massachusetts Institute of Technology (MITs) new research; and interview: United Nation (UN) sustainable energy for all (SE4ALL) special representative Kandeh Yumkella. Whats it like to be energy-poor? Kandeh Yumkella, Special Representative of the United Nations Secretary General for Sustainable Energy for All, answers that question and many more in this issue of Handshake. Yumkella recalls his own experiences in Sierra Leone to illustrate the link between energy poverty and income poverty and explains how PPPs can help.

Carbonate aquifers, located in foreland tectonic settings, could represent important thermal water resources outside the volcanic areas, supplying spas or geothermal installations. Thermal springs constitute the discharge areas of deep marine and continental groundwaters flowing within these carbonate aquifers whose hydraulic conductivity and the relevant geothermal fluid migration are strictly controlled by both the discontinuity network and the karst processes involving the foreland environment. An example of these springs occurs along the south-easternmost portion of the Apulia region (Southern Italy) where some sulphurous and warm waters (22-33 °C) flow out in partially submerged caves located along the coast, thus supplying the spas of Santa Cesarea Terme. These springs are known from ancient times (Aristotele in III century BC) and the physical-chemical features of their thermal waters resulted to be partly influenced by the sea level variations. Some hypotheses about the origin of these warm waters were proposed up to now by previous researches but some uncertainties still exist. For this reason, the area has been selected in order to define the conceptual model of the geothermal resources related to the thermal springs and, as a consequence, the origin of the thermal springs. It is one of the pilot site of the Vigor Project (Evaluation of the geothermal potential of Regions of Convergence), promoted by the Italian Ministry of Economic Development and National Research Council. Santa Cesarea Terme zone is located within the Apulia carbonate platform, the foreland of the southern Apennines, which consists of Jurassic-Cretaceous limestones, thick more than 5 km in the study area and affected by intense karst processes, resting above the Late Triassic evaporite (Burano Fm) and, unconformably, overlaid by Cenozoic calcareous successions. Belonging to a coastal area, the studied groundwater, whose top is located almost to the sea level, is involved in saltwater intrusion and therefore the salt-fresh water interface occurs at some meters below the sea level moving inland. Geological and hydrogeological surveys, including geo-electrical prospecting, and chemical and isotopic analyses of both groundwater and seawater have been carried out. Stable isotopes (?18O, ?D) were used to define the origin of the thermal waters and the recharge mechanism of the geothermal systems while the unstable isotope (3H) was determined for estimating the age of the thermal waters and to define the conceptual model of this low temperature geothermal resource. All the data have been analysed to improve the knowledge of the groundwater flow system, thus assessing the possibility of using low-temperature geothermal fluids to fulfil the thermal needs of the town of Santa Cesarea Terme. In this narrow area, the source of geogenic salinization of spring groundwater was referred to ascending very deep groundwater, more saline than current sea water.The geochemical composition and the physical features of the sampled waters suggest that thermal waters should be moving from ancient seawaters subjected to intense evaporation processes, infiltrated at great depth within the seabed substratum. Afterwards, these thermal fluids should flow up through the almost vertical structures, related to the transtensional structures, identified within a narrow sector of the studied territory.

Space heating by district heating (DH) infrastructures serve more than 100 cities in Italy, since 2010. It has steadily increased on average by about 16 Mm3/a in the last 7 years, with respect to about 8 Mm3/a in the previous 14 years; at the end of 2012 it was about 280 Mm3. The main energy source used to feed the systems is natural gas, though the renewable energy sources (mainly heat recovery from Waste-to-Energy and biomasses) are significantly growing. The geothermal resources are still marginal, but positive news are coming from a few new projects in Grado (Gorizia), Ferrara and Tuscany. Though there is a large potential for district heating and cooling (DHC) in several northern Italy cities and towns, the main reason why it did not take off yet is mainly because of the high investment required to realize the distribution networks and because of the lack of appropriate regulatory schemes and energy policies. The new Italian National Energy Strategy has identified priorities, actions and specific measures to save primary energy, by energy efficiency and sustainable use of energy resources. DHC infrastructures have a significant role in this respect, but it will be crucial to identify and remove the regulatory and non–regulatory barriers.

A characterization of medium enthalpy geothermal resources has been carried out in the Southern Apennines "Guardia Lombardi" site (Campania Region, Italy) within the framework of the Vigor Project. Due to the intense hydrocarbon exploration carried out in Italy since the '50, a wide public dataset of well data and seismic reflection profiles is available for the study site. Moreover, a scientific cooperation with the ENI Italian Oil Company has been established in order to access to more detailed dataset also including wells information and core samples. A three-dimensional geological model of the reservoir-caprock system has been developed through an integrated interpretation of the available geological, geophysical, hydrogeological and geochemical information in the study area. The geothermal reservoir of "Guardia Lombardi" site is constituted by the Cretaceous-Eocene fractured shallow water carbonates belonging to the Apulian platform. Such units have been structured in a buried antiformal stack during the Apennine orogenesis. The reservoir fluids are mainly composed of CO2, which rests above of brackish water in the central part of the deep carbonatic aquifer culmination (i.e., Monte Forcuso 1 well). Conversely along the flanks of the buried anticline (e.g., Bonito 1 Dir, Ciccone 1 wells) the reservoir fluids consist of saline water, not showing any free gas phase. The temperature of this fluids recorded into the reservoir are 120-125°C at the depth of about 3000 m below the ground level (e.g. Bonito 1 well). Given the quite good permeability of the fractured carbonate rocks, numerical simulation performed in this work estimated that a water production of about 13.5-20 kg/s might be achieved according to the chosen technical solution (a single production well vs production- reinjection doublet). Results confirm that the "Guardia Lombardi" site represents an interesting area for the exploitation of this medium enthalpy geothermal resource.

Geothermal energy is a clean, green renewable resource, which can be utilized for power generation, heating, cooling, and could effectively replace oil, gas, and coal. In recent years, oil companies have put more efforts into exploiting and utilizing geothermal energy with advanced technologies for heat-tracing oil gathering and transportation, central heating, etc., which has not only reduced resource waste, but also improved large-scale and industrial resource utilization levels, and has achieved remarkable economic and social benefits. Based on the analysis of oilfield geothermal energy development status, resource potential, and exploitation and utilization modes, the advantages and disadvantages of harnessing oilfield geothermal resource have been discussed. Oilfield geothermal energy exploitation and utilization have advantages in resources, technical personnel, technology, and a large number of abandoned wells that could be reconstructed and utilized. Due to the high heat demand in oilfields, geothermal energy exploitation and utilization can effectively replace oil, gas, coal, and other fossil fuels, and has bright prospects. The key factors limiting oilfield geothermal energy exploitation and utilization are also pointed out in this paper, including immature technologies, lack of overall planning, lack of standards in resource assessment, and economic assessment, lack of incentive policies, etc.

Economic growth in Central America has increased rapidly over the past 20 years. Currently, the gross domestic product (GDP) per capita for the six Central American countries of Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama averages approximately US$3,600. However, economic disparity in the Latin American region is the highest in the world. Despite impressive growth, 20 million people or half of the population in Central America are classified as poor. This assessment of the geothermal potential module is the fourth in the series; it provides an analysis of the energy context in the region focusing on the technology and past experiences of geothermal resources. The study aims to identify the challenges associated with development of geothermal generation, including physical, financial, regulatory and institutional barriers, and it outlines some possible strategies to overcome them at the regional and country-specific level with a view to establish a basis for policy dialogue and to provide decision-makers a reference document with a regional outlook. Energy, particularly electricity, is critical for economic development. It is needed to power machinery that supports income-generating opportunities. Countries that have affordable and reliable energy can more easily attract both foreign and domestic capital. Central America's vulnerability to external shocks in the energy sector has increased over the last years. The region depends on foreign supply of fossil fuels (oil, coal). Since the share of thermal generation in power supply has increased significantly in the last decade, exceeding installed capacity for hydropower, the rise and volatility of oil prices has a dramatic effect today on the region's economy. Together with integration, it has become increasingly clear that the region must develop its local energy endowment, which has generated a strong interest in renewable energy sources and technologies, such as hydropower, geothermal, and wind. Given its potential in the region, geothermal energy has attracted the attention of policymakers and private investors as a resource to further develop and supplement hydroelectric generation (and to reduce dependency on thermal generation).

La introducción de energías renovables en el abastecimiento de sistemas de climatización cobra cada vez más importancia, por lo que se hace especialmente relevante la utilización de sistemas de generación de calefacción y refrigeración a través de fuentes de energías renovables. Una de ellas, la geotermia de muy baja entalpía, presenta unos bajos costes de mantenimiento y operación, y consigue reducir la dependencia de recursos energéticos exteriores, así como la disminución del impacto medioambiental producido y la consecuente reducción de gases de efecto invernadero.

This issue includes the following headings: renewable energy: wind and solar; energy efficiency: green building; and green finance: infrastructure finance.

14 p., 5 fig., 12 tabl.; International audience; The Triassic sandstone reservoirs of the Paris Basin (France) have attractive geothermal potential for district heating. However, previous exploitations of these reservoirs have revealed re-injection problems preventing from further geothermal operations. To avoid these crucial problems, a possible option would be to inject the exploited Triassic brines in the Dogger aquifer characterized by better re-injection properties. However, this solution might trigger geochemical reactions that may impact negatively the properties of the Dogger aquifer, notably its porosity. This study, based on numerical simulations, aims to identify and quantify the possible consequences of the thermo-hydro-geochemical processes induced by the re-injection of the cooled Triassic brines into the Dogger aquifer. Initial batch simulations show potential occurrences of precipitation/dissolution reactions that could potentially impact the Dogger porosity: dissolution of disordered dolomite and calcium sulfate; precipitation of silicates, barium sulfate and sulfides. In a second step, 2D reactive transport modeling was performed. The results obtained up to now suggest that the impact of the Triassic re-injection could be limited to the first fifty meters around the injection well and be insignificant in terms of porosity variation (< 0.14 percentage point). However, at this stage, species which are sensitive to redox conditions, such as iron and sulfur, are not yet considered. Therefore, this reactive transport model does not take into account some of the reactions identified in the batch modeling as potentially induced during the Triassic re-injection into the Dogger, such as barium sulfate and sulfides precipitation. This is planned to be done in upcoming modeling tasks.

8 p., 13 fig., 2 tabl.; International audience; Geothermal energy of the carbonate Dogger aquifer of the Paris Basin is exploited for heating since 1970s using geothermal well doublet technology where the warm produced waters (57-85°C) is extracted by a production well and re-injected after used as cooled waters (about 40°C) in the same aquifer via a different well. The injection of the cooled waters into the Dogger reservoir disturbs the initial thermodynamic equilibrium between the Dogger aquifer phases. This creates a cold and growing bubble around the injection well which risks propagating toward the production wells. This study, based on geochemical monitoring and field data analyses, aims to identify chemical precursor(s) of the thermal decrease in the production well field. Ca and HCO3 concentrations do not appear to be relevant precursors, because they are linked to fast mineral dissolution/precipitation reactions (carbonates). However Si concentration could be an appropriate precursor of the temperature drop, because it depends only on slow mineral reactions (silicates dissolution/precipitation). The results of this analysis are presented and discussed in this paper.

A well Grado-1 was drilled down to 1108 m reaching mesozoic shelf carbonates which occur in the structural highs in the Lignano – Grado area. The well was completed with geophysical logs in the open hole interval from -700 to -1108 m. The drilling bit met the nummulitic shelf paleogenic limestones at -616,5 m and Mesozoic (Upper Cretaceous) platform around -1007 m. About 400 m thick Palaeogene interval appears affected by open fractures which we consider linked up to a reverse fault and a tectonic duplex of the Palaeogene limestone interval is hypothesized. The feature corresponds to the outer deformation front of the Dinaric thrusts system and looks still active. Palaeogene limestone sequence is analogous to the outcrops in the northern Istria and in the stratigraphy in the oil wells offshore northern Dalmatia. The drilling target was the characterization of the nature of the geothermal resources in the Friuli lower plain and lagoons region, following the long-term investigations of the Department of Civil and Environmental Engineering of the Trieste University. The geothermal resource was found in correspondence of the above mentioned open fracture zone and below it, with salty hot waters at a temperature of 42°C, increasing with depth, and a flow of 25 l/s arriving to the surface with 2,8 pressure bars.

This strategic framework serves to guide and support the operational response of the World Bank Group (WBG) to new development challenges posed by global climate change. Unabated, climate change threatens to reverse hard-earned development gains. The poorest countries and communities will suffer the earliest and the most. Yet they depend on actions by other nations, developed and developing. While climate change is an added cost and risk to development, a well-designed and implemented global climate policy can also bring new economic opportunities to developing countries. Climate change demands unprecedented global cooperation involving a concerted action by countries at different development stages supported by "measurable, reportable, and verifiable" transfer of finance and technology to developing countries. Trust of developing countries in equity and fairness of a global climate policy and neutrality of the supporting institutions is critical for such cooperation to succeed. Difficulties with mobilizing resources for achieving the millennium development goals and with agreeing on global agricultural trade underscore the political challenges. The framework will help the WBG maintain the effectiveness of its core mission of supporting growth and poverty reduction. While recognizing added costs and risks of climate change and an evolving global climate policy. The WBG top priority will be to build collaborative relations with developing country partners and provide them customized demand-driven support through its various instruments from financing to technical assistance to constructive advocacy. It will give considerable attention to strengthening resilience of economies and communities to increasing climate risks and adaptation. The operational focus will be on improving knowledge and capacity, including learning by doing. The framework will guide operational programs of WBG entities to support actions whose benefits to developing countries are robust under significant uncertainties about future climate policies and impacts-actions that have "no regrets."

Due to the scarcity of heat flow data in the region of Ensenada, Baja California (Mexico), the present study calculated them using the silica geothermometer technique. The average heat flow value determined was 123.33 ± 35.57 mW m–2 (2.95 ± 0.85 HFU). Four zones within the study area, related to the main fault systems of the region, were found to have high hydrothermal activity. The potential use of geothermal resources in the area is feasible as it is considered a low geothermal system with water temperature values, above the static water level, that vary from 30ºC to 108ºC.

Deep borehole temperature data, thermal conductivity measurements and heat flow measurements (on land and in offshore areas) were alalyzed and complied to obtain temperature and heat flow maps of Italy and surrounding marine areas. The results are maps of temperatures at various depths (100, 2000, 3000 m) and heat flow anomalies that describe the lateral changes in temperature and heat flow distributions across the Italian peninsula and marine areas.