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.     

Horizontal drilling assessment in Western Canada

The first horizontal well was drilled in Saskatchewan in 1987. Since then, the number of horizontal wells drilled has escalated rapidly, averaging approximately 500 per year since 1993. When combined with horizontal wells drilled in Alberta, the major Canadian oil-producing province, the total number drilled in 1995 was 978. This total exceeds the National Energy Board (NEB) projected maximum of 816 wells per year. The NEB projections were based on a break-even point for the drilling of horizontal wells of a return of CDN $285,000 using a discount rate of 15%. This corresponded to a cumulative production from each individual well of some 11,000 m³. The introduction of a royalty-free production volume of 12,000 m³ per horizontal well in Saskatchewan was instrumental in stimulating the rapid expansion in the use of horizontal wells and helping Canada to exceed the forecasted drilling level. Within Saskatchewan, daily production from 1964 active horizontal wells is in excess of 20,000 m³. Comparative analysis indicates that the average daily production per well has increased from approximately by 40% with the advent of horizontal wells. In total production terms, provincial production has increased from 11.7 million cubic metres in 1989 to 20.9 million m³ in 1996. This represents an increase of almost 79% based primarily on the extensive use of horizontal wells. In 1996, horizontal wells produced 36% of the province's oil from 12% of the active wells. In the southeastern producing area of Saskatchewan, the Williston Basin, declining oil-production has jumped 100%, with horizontal wells accounting for approximately 50% of total regional production. Pay zones in this area, as in most of the province, tend to be relatively thin, with net pay frequently less than 5 m. The modest investment of some CDN $5 million in government research funding 10 years ago to simulate the development of horizontal wells, combined with a favourable royalty structure, has been at least partially responsible for very significant benefits to the provincial economy. In Saskatchewan, horizontal wells have (i) paid over CDN $400 million in royalties since 1990, (ii) annually generated CDN $525 million in investment and (iii) sustained 4350 jobs. Details pertaining to the Winter Cummings Sand Pool and others as examples of the success of the horizontal well program in Saskatchewan are discussed in this paper.     

Biofuels and biochemicals production from forest biomass in Western Canada

Biomass can be used for the production of fuels, and chemicals with reduced life cycle (greenhouse gas) emissions. Currently, these fuels and chemicals are produced mainly from natural gas and other fossil fuels. In Western Canada, forest residue biomass is gasified for the production of syngas which is further synthesized to produce different fuels and chemicals. Two types of gasifiers: the atmospheric pressure gasifier (commercially known as SilvaGas) and the pressurized gasifier (commercially known as RENUGAS) are considered for syngas production. The production costs of methanol, (dimethyl ether), (Fischer-Tropsch) fuels, and ammonia are $0.29/kg, $0.47/kg, $0.97/kg, and $2.09/kg, respectively, for a SilvaGas-based gasification plant with a capacity of 2000 dry tonnes/day. The cost of producing methanol, DME, F-T fuels, and ammonia in a RENUGAS-based plant are $0.45/kg, $0.69/kg, $1.53/kg, and $2.72/kg, respectively, for a plant capacity of 2000 dry tonnes/day. The minimum cost of producing methanol, DME, F-T fuels, and ammonia are $0.28/kg, $0.44/kg, $0.94/kg, and $2.06/kg at plant capacities of 3000, 3500, 4000, and 3000 dry tonnes/day, respectively, using the SilvaGas-based gasification process. Biomass-based fuels and chemicals are expensive compared to fuels and chemicals derived from fossil fuels, and carbon credits can help them become competitive.     

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.     

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。     

Geothermal areas in Pakistan

In this paper an attempt has been made to correlate the tectonic and geologic features with surface manifestations of geothermal activity in Pakistan to delineate prospective areas for exploration and development of geothermal energy. Underthrusting of the Arabian plate beneath the Eurasian plate has resulted in the formation of Chagai volcanic arc which extends into Iran. Quaternary volcanics in this environment, along with the presence of thermal springs, is an important geotectonic feature revealing the possible existence of geothermal fields. Geothermal activity in the northern areas of Pakistan, as evidenced by thermal springs, is the likely result of collision and underthrusting of the Indian plate beneath the Eurasian plate. Numerous hot springs are found along the Main Mantle thrust and the Main Karakorum thrust in Chilas and Hunza areas respectively. The concentration of hot springs in Sind Province is also indicative of geothermal activity. A string of thermal seepages and springs following the alignment of the Syntaxial Bend in Punjab Province is also noteworthy from the geothermal viewpoint.In Baluchistan Province (southwest Pakistan), Hamun-e-Mushkhel, a graben structure, also shows geothermal prospects on the basis of aeromagnetic studies.     

Geothermal development in Thailand

San Kampaeng and Fang geothermal areas are considered areas of interest for the exploitation of geothermal energy. The technologies of exploration and development have been studied by Thai scientists and engineers during the past four years. The first geothermal deep exploration well was drilled, in cooperation with Japan International Cooperation Agency (JICA), in the San Kampaeng geothermal area. In 1985, supplementary work is planned to define the deep structural setting in greater detail before starting to drill the next deep exploration well. In Fang geothermal area some shallow exploitation wells have been drilled to obtain fluid to feed a demonstration binary system of 120 kWe, with the technical cooperation of BRGM and GEOWATT, France. The plant will be installed next fiscal year.     

Geothermal experience in Hungary

Geothermal fluids in Hungary are exploited in 650 wells and connected heating systems. The highest emergence temperature is about 95°C. Scaling problems are being tackled by chemical and physical techniques. Reinjection tests are now under way to comply with environmental regulations.     

Geothermal activity in Turkey

Turkey is located on the Alpine tectonic belt with many grabens, acidic volcanism, hydrothermal alteration zones, numerous hot springs and fumaroles. The data gathered indicate that Turkey has a high geothermal energy potential. Geothermal research began in the 1960s implemented by the Mineral Research and Exploration General Directorate (MTA). Exploration began at Denizli-Kizildere in 1968. Further studies revealed the field to be commercially exploitable and a geothermal power-plant with a capacity of 20 MW started electricity generation in 1984. Currently there are numerous fields being explored and developed for electrical and non-electrical uses.     

Geothermal development in Romania

Exploration for geothermal resources began in Romania in the early 1960s, based on a detailed geological exploration program for hydrocarbon resources that had a capacious budget and enabled the identification of eight geothermal areas. Over 200 wells drilled to depths between 800 and 3500 m have indicated the presence of low-enthalpy geothermal resources (40–120 °C). Completion and experimental production from over 100 wells during the past 25 years has led to the evaluation of the exploitable heat resources of the geothermal reservoirs. The proven reserves, with the wells that have already been drilled, amount to about 200,000 TJ for 20 years. The main geothermal systems discovered on Romanian territory are in porous permeable formations such as sandstones and siltstones (Western Plain and the Olt Valley) or in fractured carbonate formations (Oradea, Bors, and north of Bucharest). The total thermal capacity of the existing wells is about 480 MW_t (for a reference temperature of 25 °C). Only 152 MW_t of this potential is currently being exploited, from 96 wells (35 of which are used for health and recreational bathing), producing hot water in the temperature range 45–115 °C. In 2002 the annual energy utilisation from these wells was about 2900 TJ, with a capacity factor of 0.6. More than 80% of the wells are artesian producers, 18 wells require anti-scaling chemical treatment and six are reinjection wells. During the period 1995–2002, 15 exploration-production geothermal wells were drilled and completed, two of which were dry holes. Drilling was financed by the geological exploration fund of the State Budget, to depths varying between 1500 and 3500 m. Progress in the direct utilisation sector of geothermal resources has been extremely slow because of the difficulties encountered during the transition period from a centrally planned to a free-market economy; geothermal production is at present far below the level that could be expected from its assessed potential, with geothermal operations lagging behind in technology. The main obstacle to geothermal development in Romania is the lack of domestic investment capital. In order to stimulate the interest of potential investors from developed countries and to comply with the requirements of the large international banks, an adequate legal and institutional framework has been created, adapted to a market-oriented economy.     

Geothermal applications in Turkey

Geothermal energy is mostly utilised in direct applications in Turkey. The equivalent of 61,000 residences are currently heated by geothermal fluids. A total of 665 MW_t is utilised for space heating of residential, public and private property, and 565,000 m² of greenhouses. Geothermal fluids are also used in 195 spas (327 MW_t), bringing the total direct use capacity to 992 MW_t. ORME Geothermal Inc. has completed the engineering design of a geothermal district heating system that serves the equivalent of nearly 300,000 residences. A total of 170 geothermal fields have been explored so far in Turkey. At Kizildere a single-flash power plant with 20.4 MW_e installed capacity is integrated with a factory producing liquid CO₂ and dry-ice. A binary cycle power plant with an installed capacity of 25 MW_e will be constructed shortly at Aydin/Germencik. The proven geothermal heat capacity, according to data from existing geothermal wells and natural discharges, is 3132 MW_t (I. Akkus, MTA General Directorate, oral communication, January 2003).     

Geothermal development in Nicaragua

In order to meet national energy requirements, Nicaragua has had to direct its attention towards sources of “alternative energy”, such as geothermal. Excellent geothermal prospects exist in this country, for which reason the Revolutionary Government has deemed it convenient to direct its energy policy towards this alternative source. Studies carried out during past years have led to the selection of nine areas in western Nicaragua, four of which were earmarked Very High Priority because they contain high enthalpy geothermal fields, three areas were earmarked High Priority and only two Low Priority. The positive results obtained in the Momotombo geothermal project have become an incentive to continue research and development nation-wide.At present, a power plant is operating with 35 MW at the Momotombo geothermal field; another 35 MW power plant is under construction in the same field; the El Hoyo-Monte Galan project is in the pre-feasibility phase and surveys are under way throughout national territory.     

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.     

Geothermal manifestations in Nepal

A number of thermal springs have been located in different parts of Nepal. As very few systematic studies have been carried out so far very little is known on their chemistry and genesis. Talalov (1973) and Bhattarai have made an inventory of the thermal springs of Nepal and have provided some relevant information on about forty of them. Dikshit and Bhattarai and Bashyal have made preliminary investigations of some thermal springs of Dhawalagiri and Karnali Zone, and Lumbini Zone respectively. The present paper deals with some of the geological and chemical studies of the thermal springs undertaken by the author.