Geothermal resources in Algeria

The geothermal resources in Algeria are of low-enthalpy type. Most of these geothermal resources are located in the northeastern of the country. There are more than 240 thermal springs in Algeria. Three geothermal zones have been delineated according to some geological and thermal considerations: (1) The Tlemcenian dolomites in the northwestern part of Algeria, (2) carbonate formations in the northeastern part of Algeria and (3) the sandstone Albian reservoir in the Sahara (south of Algeria). The northeastern part of Algeria is geothermally very interesting. Two conceptual geothermal models are presented, concerning the northern and southern part of Algeria. Application of gas geothermometry to northeastern Algerian gases suggests that the reservoir temperature is around 198 °C. The quartz geothermometer when applied to thermal springs gave reservoir temperature estimates of about 120 °C. The thermal waters are currently used in balneology and in a few experimental direct uses (greenhouses and space heating). The total heat discharge from the main springs and existing wells is approximately 642 MW. The total installed capacity from producing wells and thermal springs is around 900 MW.     

Chilean geothermal resources and their possible utilization

Most of the hot spring areas in Chile are located along the Andean Cordillera, associated with Quaternary volcanism. The volcanic—geothermal activity is mainly controlled by the subduction processes of the Nazca and Antarctic oceanic plates under the South America continental plate, and occurs at three well-defined zones of the Chilean Andes: the northern zone (17°30′–28°S), the central—south zone (33φ–46°S) and the southern-most or Austral zone (48°–56°S).Some tested high temperature geothermal fields, and geological and geochemical surveys of many other hot spring areas, evidence a great potential of geothermal resources in this country. Both electrical and non-electrical applications of this potential are considered in this paper.Taking into account the potentially available geothermal resources, the development of natural resources, the geographic and social—economic conditions existing in the different regions of Chile, it is concluded that power generation, desalination of geothermal waters, recovery of chemicals from evaporite deposits and brines and sulfur-refining are the main possible applications of geothermal energy in northern Chile; in central—south Chile geothermal energy is suitable for agribusiness such as greenhouses, aquaculture and animal husbandry.     

Geothermal resources in Saudi Arabia

The aim of this reconnaissance of the volcanic harrats and thermal springs in the Kingdom of Saudi Arabia was to identify areas of potential geothermal interest.On the harrats, the petrographic evolution of the various magmatic series was systematically studied, placing each in its structural context, and tackling the problem of the possible existence of reservoirs. At this stage of our study, it is not possible to approach the problem of reservoir recharge. Hydrogeochemical studies were carried out on the thermal springs.     

Geothermal resources of Hachijojima

Hachijojima is a gourd-shaped volcanic island in the Pacific Ocean. Nishiyama and Higashiyama volcanoes consist of basalt lava and associated pyroclastic rocks. A promising geothermal resource was found in south Higashiyama, associated with an uplift of Tertiary rocks consisting of mainly andesite lava and related pyroclastic rocks, overlain by Quaternary volcanic rocks. Steep high-temperature (over 250°C) and high-pressure gradients occur in the deeper portion of the system near the Tertiary–Quaternary contact, indicating the presence of a cap rock. The cap rock formed by deposition of hydrothermal minerals. Geothermal fluid ascends from the deeper portions to shallow depths along vertical fractures through the cap rock. These vertical fractures form the geothermal reservoir in the Tertiary formation. Three wells were drilled into these vertical fractures, and approximately 30 t/h of superheated steam was obtained from each well during flow tests. The geothermal fluid is mainly a mixture of seawater and meteoric water in an approximate ratio of 1 to 2, based on chemical analyses, with a portion of volcanic gas included. At present a 3.3 MW_e, geothermal power plant is being constructed here.     

Geothermal energy resources and development in Iran

Interest in geothermal energy originated in Iran when James R. McNitt, a United Nations geothermal expert, visited the country in December 1974. In 1975, a contract among the Ministry of Energy, ENEL (Entes Nazionale per L’Energia Elettrica) of Italy and TB (Tehran Berkeley) of Iran was signed for geothermal exploration in the north-western part of Iran. In 1983, the result of investigations defined Sabalan, Damavand, Khoy-Maku and Sahand regions as four prospected geothermal sites in north-western Iran.From 1996 to 1999, a countrywide geothermal energy resource exploration project was carried out by Renewable Energy Organization of Iran (SUNA) and 10 more potential areas were indicated additionally.Geothermal potential site selection using Geographic Information System (GIS) was carried out in Kyushu University in 2007. The results indicated 8.8% of Iran as prospected geothermal areas in 18 fields.Sabalan as a first priority of geothermal potential regions was selected for detailed explorations. Since 1995, surface exploration and feasibility studies have been carried out and five promising areas were defined. Among those prospective areas, Northwest Sabalan geothermal filed was defined for detailed exploration to justify exploration drilling and to estimate the reservoir characteristics and capacity.From 2002 to 2004, three deep exploration wells were drilled for evaluation of subsurface geological conditions, geothermal reservoir assessment and response simulation. Two of the wells were successful and a maximum temperature of 240 °C at a depth of 3197 m was recorded. As a result of the reservoir simulation, a 55-MW power plant is projected to be installed in the Sabalan field as a first in geothermal power generation. To supply the required steam for the geothermal power plant (GPP) 17 deep production and reinjection wells are planned to be drilled this year.     

Geothermal resources in Iran: The sustainable future

Because of disadvantages of fossil fuels, renewable energy sources are getting importance for sustainable energy development and environmental protection. Among the renewable sources, Iran has geothermal energy potential. The Iranian government is considerable attention to the utilization of renewable energy, especially wind, solar and geothermal energies. Due to recent advancements in geothermal energy, many investors in the country have become interested in investing in this type of energy. Geothermal studies in Iran started in 1975 with a cooperative between the ministry of Energy of Iran and ENEL Company from Italy. Preliminary studies indicated potential for geothermal power generation in four areas in northern Iran (Khoy-Maku, Sabalan, Sahand and Damavand at Azarbaijan Gharbi, Ardebil, Azarbaijan Sharghi and Tehran provinces), respectively. Geothermal development in Iran has gained momentum in the last five years with increased exploration and industry growth in the country. Iran is developing a geothermal plant for power production. Iran government plans to build 2000 MW of renewable energy capacity over the next five years. Total projected use (geothermal capacity) has been estimated 100 MW at the end of 2010. Exploration drilling is currently in-progress for Meshkinshahr project in North-Western Iran. The Sabalan geothermal power plant is expected to produce 50 MW electric powers in 2011. The plants are planned by Iran Ministry of Energy and the Renewable Energy Organization of Iran (SUNA). This study presents a brief introduction to the resource, status and prospect of geothermal energy in Iran.     

Geothermal energy use in hydrogen liquefaction

We propose the use of geothermal energy for hydrogen liquefaction, and investigate three possible cases for accomplishing such a task including (1) using geothermal output work as the input for a liquefaction cycle; (2) using geothermal heat in an absorption refrigeration process to precool the gas before the gas is liquefied in a liquefaction cycle; and (3) using part of the geothermal heat for absorption refrigeration to precool the gas and part of the geothermal heat to produce work and use it in a liquefaction cycle (i.e., cogeneration). A binary geothermal power plant is considered for power production while the precooled Linde–Hampson cycle is considered for hydrogen liquefaction. A liquid geothermal resource is considered and both ideal (i.e., reversible) and non-ideal (e.g., irreversible) system operations are analyzed. A procedure for such an investigation is developed and appropriate performance parameters are defined. Also, the effects of geothermal water temperature and gas precooling temperature on system performance parameters are studied. The results show that there is a significant amount of energy savings potential in the liquefaction work requirement as a result of precooling the gas in a geothermal absorption cooling system. Using geothermal energy in a cogeneration scheme (power production and absorption cooling) also provides significant advantages over the use of geothermal energy for power production only.     

Review of wind energy use in Algeria

Most scientists now agree that human-induced global climate change poses a serious threat to both society and the Earth's ecosystems. Renewable energy holds the key to future prosperity and a healthy global environment and is considered as a promising way to solve the problem of environmental pollution such as major environmental accidents, water pollution, maritime pollution, land use and sitting impact, radiation and radioactivity, solid waste disposal, hazardous air pollutants, ambient air quality (CO, CO₂, SO_x, NO_x effluent gas emissions), acid rain, stratospheric ozone depletion, and global warming (GHG). Solar, wind and hydrogen power can be considered as potential renewable energy sources in Algeria. The share of renewable energy sources in Algeria primary energy supply is relatively low compared with European countries, though the trends of development are positive. One of the main strategic priorities of New Energy Algeria (NEAL) which is Algeria's renewable energy agency (government, Sonelgaz and Sonatrach), is striving to achieve a share of renewable energy sources in primary energy supply of 10–12% by 2010. IEA projects that the fastest growing sources of energy will be supplied by renewables. Much of this capacity will be installed in developing nations where solar and wind electric power is already competitive. Clearly, the nation that can capture a leadership position has potential for substantial economic returns. The article presents a review of the present wind energy situation and assessed potential of wind energy sources in Algeria in particular the southwest region of Algeria (Adrar, Timimoun and Tindouf).     

Prospects of hydrogen production potential from renewable resources in Algeria

Hydrogen production from renewable energies is a key part in the energy transition to realize a sustainable energy economy for both developed and developing nations. For Algeria, successful energy transition toward a hydrogen economy will require the establishment of its potential. This study was conducted to estimate the potential for producing hydrogen from renewable resources in Algeria. The renewable energies considered are: solar photovoltaic and wind. To accomplish this objective, first, we analyzed renewable resource data both statistically and graphically using Geographical Information System (GIS), a computer-based information system utilized to create and visualize the spatial distribution of the geographic information. Then, the study will evaluate the availability of renewable electricity production potential from these key renewable resources. The potential for the hydrogen production, via the electrolysis process with wind and solar photovoltaic electricity, is described with maps showing it per unit area in each region. Finally, the results of the estimated hydrogen potential from both resources for each region are compared and significant conclusions are drawn.     

Energy resources and use: The present situation and possible paths to the future

Recent estimates and forecasts of the oil, gas, coal resources and their reserve/production ratio, nuclear and renewable energy potential, and energy uses are surveyed. The impact of the rapidly growing economies of the highly populated countries, as well as of the concern about global warming, are presented and assessed. A brief discussion of the status and prospects of fossil, nuclear and renewable energy use, and of power generation (including hydrogen, fuel cells, micro power systems, and the futuristic concept of generating power in space for terrestrial use, is given. A brief summary of the energy research effort and budgets in the US, and EU are presented, and ways to resolve the problem of the availability, cost, and sustainability of energy resources alongside the rapidly rising demand are discussed. The author's view of the promising energy research and development (R&D) areas, their potential, foreseen improvements and their time scale, and last year's trends in government funding are presented.     

Energy resources and use: The present (2008) situation and possible sustainable paths to the future

Recent estimates and forecasts of the oil, gas, and coal resources and their reserve/production ratio, nuclear and renewable energy potential, and energy uses are surveyed. A brief discussion of the status and prospects of fossil, nuclear and renewable energy use, and of power generation (including hydrogen, fuel cells, micropower systems, and the futuristic concept of generating power in space for terrestrial use) is given. Ways to resolve the problem of the availability, cost, and sustainability of energy resources alongside the rapidly rising demand are discussed. The author's view of the promising energy R&D areas, their potential, foreseen improvements and their time scale, and last year's trends in government funding, are presented.     

Geothermal resources in the shallow, unsaturated zone of the Wiesbaden spa district, Germany

The geothermal energy potential of the Wiesbaden spa district continues to be largely untapped. Although the thermal water is being utilized, any other activity liable to disturb the hydraulic regime of the thermal springs is prohibited. The geothermal potential of the unsaturated zone in the spa district has been mapped, although the zone must be regarded as a thermal insulator rather than a good conductor. The results of the mapping revealed the presence of a number of heat anomalies that could be exploited in the future; further economic benefits could be gained from installing the heat transfer units during road works. The modelling studies considered two possible scenarios: direct heating and heat pump usage. The results indicate that heat pumps are the more efficient option, yielding a thermal capacity of approximately 100 W/m².     

北京平原地热资源与地热供暖

本文对北京平原地区地热资源条件和供暖现状进行了概述,分析了地热供暖技术的特点、优势以及当前制约其推广发展的“瓶颈”,针对北京平原地热资源的可持续发展提出了两点具体建议。     

Current Geothermal Energy Potential in Turkey and Use of Geothermal Energy

Turkey is the seventh-richest country in the world in geothermal potential. The first geothermal researches and investigations in Turkey started by the Turkey Mineral Research and Exploration Institute (MTA) in the 1960s. Upon this, 170 geothermal fields have been discovered by MTA, in which 95% of them are low-medium enthalpy fields, which are suitable mostly for direct-use applications. The overall geothermal potential in Turkey is about 38,000 MW. Of this potential, around 88% is appropriate for thermal use (temperature less than 473 K) and the remainder is appropriate for electricity production (temperature more than 473 K). Turkey has extended its involvement in geothermal energy projects, supported by loans from the Ministry of Environment, and geothermal energy is expected to increase substantially in the coming years. Overall, Turkey has an estimated 4,500 MW of geothermal power production potential.     

Polygeneration and efficient use of natural resources

The consumption of natural resources has been increasing continuously during recent decades, due to the growing demand caused by both the economic and the demographic rise of global population. Environmental overloads that endanger the survival of our civilization and the sustainability of current life support systems are caused by the increased consumption of natural resources—particularly water and energy—which are essential for life and for the socio-economic development of societies. While not yet well utilized, process integration and polygeneration are promising tools which reach the double objective of increasing the efficiency of natural resources, and also minimizing the environmental impact. This paper discusses the concepts of polygeneration and energy integration and various examples of polygeneration systems: (i) sugar and energy production in a sugarcane factory; (ii) district heating and cooling with natural gas cogeneration engines and (iii) combined production of water and energy. It is clearly evident that polygeneration systems which include appropriate process integration significantly increase the efficient use of natural resources.     

Geothermal energy in Canada

Since 1973 an effort has been made to identify and assess geothermal resources within Canada. Although the task is far from complete, two areas have been examined in some detail: the recent volcanic complex of Meager Mountain, British Columbia, and the Western Platform in British Columbia, Alberta and Saskatchewan. It has been found that there are substantial resources associated with both, but of different character. At Meager Mountain high-temperature water will probably eventually be used for the generation of electrical power, whereas the low- to medium-temperature resources of the Basin are suitable for space heating and direct use. The useful accessible resource base in the waters of the Western Platform is very large, and reserves, estimated as 1% of the resource base are an order of magnitude greater than the thermal equivalent of Canadian oil reserves. In eastern Canada, where conventional energy supplies are more expensive, prospects for geothermal resources are not generally favourable, except in small areas. Development of geothermal resources in Canada is hindered by the absence of an established industry and, except in the Province of British Columbia, of legislation for the control of exploration and development of geothermal resources.