Aniko Toth

University of Miskolc · Institute of Petroleum and Natrual Gas

ABS TRACT The European Union (EU) is one of the first major regions to propose binding greenhouse-gas (GHG) emission reduction targets. Specifically, the EU aims to cut GHG by at least 55% by 2030 and become the first climate-neutral continent by 2050. To achieve these targets, the EU has set up a series of public funding instruments to support pro...

The world is experiencing the first truly global energy crisis in history, and the situation is especially perilous in Hungary. Hungary, like the rest of Europe, is at the epicenter of the energy market turmoil. Hungary has never been energy-independent: it has always imported the energy it needed. Currently, however, the country's overall energy c...

Production of electricity using geothermal energy started in 1904 at Larderello, Italy with an experimental 10 kWe generator. This was followed by a 250 kWe commercial unit in 1913. Italy was the world's only industrial generator of geothermally fueled electricity until 1958 when New Zealand came on-line with a 11.2 MWe unit built at Wairakei. By 1...

This article summarizes geothermal energy applications worldwide for direct utilization and electric power generation. The data is based on the Reykjavik, Iceland World Geothermal Congress (WGC2020+1) world reports. Thse reports were based on country update papers received from 88 countries and regions. Another 26 countries were added to the list b...

Production of electricity using geothermal energy started in 1904 at Larderello, Italy with an experimental 10 kWe generator. This was followed by a 250 kWe commercial unit in 1913. Italy was the world’s only industrial generator of geothermally fueled electricity until 1958 when New Zealand came on-line with a 11.2 MWe unit built at Wairakei. By 1...

There are many compelling arguments for using geothermal energy in Hungary. One of the most important is that the country could thereby exploit its abundant, relatively untapped network of geothermal reservoirs. These are considerably warmer and closer to the surface than in most of Europe. In the foreseeable future, Hungary's geothermal resources...

There are many compelling arguments for using geothermal energy in Hungary. One of the most important is that the country could thereby exploit its abundant, relatively untapped network of geothermal reservoirs. These are considerably warmer and closer to the surface than in most of Europe. In the foreseeable future, Hungary’s geothermal resources...

This chapter summarizes statistical data for geothermal energy applications worldwide, for direct utilization and electric power generation, in 2019. The data is based on 2020 World Geothermal Congress (WGC2020) world reports. These reports were based on country update papers received from 88 countries and regions. Another 26 countries were added t...

The application of hydraulic fracturing in geothermal reservoirs requires the con- sideration of aspects related to temperature, geology, and in-situ stresses. This research com- pares the application of hydraulic fracturing for geothermal purposes in Rotliegend sand- stones of sedimentary origin in the North German Basin with that of a Granodiorit...

This paper presents a review of the worldwide applications of geothermal energy for direct utilization and updates the previous survey carried out in 2015. We also compare data from WGC1995, WGC2000, WGC2005, WGC2010, and WGC2015 presented at World Geothermal Congresses in Italy, Japan, Turkey, Indonesia and Australia. As in previous reports, an ef...

This paper presents a review of the worldwide applications of geothermal energy for direct utilization and updates the previous survey carried out in 2015. We also compare data from WGC1995, WGC2000, WGC2005, WGC2010, and WGC2015 presented at World Geothermal Congresses in Italy, Japan, Turkey, Indonesia and Australia. As in previous reports, an ef...

This paper gives a brief review of the history of geothermal energy in Hungary and discusses the present state of Hungary's geothermal energy production and utilization. Hungary's excellent geothermal potential is of course well-known. Traditionally, the country's geothermal energy production was used for direct heat supply, with most of the therma...

Hungary is known for its good geothermal potential and Budapest, its capital, is especially well provided for in this regard. Thermal water has been used there since ancient times and even now its famous spas are a major source of Budapest's popularity among tourists. Until recently, however, there was no accurate yet practical publication to compr...

Special Topics: Geothermal Energy: Prospecting, Production, and Utilization CVEN 4838-200 and CVEN 5838-201 Room ECCE 1B47 July 09-August 09, 2019 This introductory summer course covers the natural conditions, production, utilization, and environmental impact of geothermal energy. We provide students with both a scientific and practical understandi...

Hungary’s excellent geothermal potential is well- known. Mostly the thermal water is used for direct heat utilization. Based on the 2016 Geothermal Atlas of Hungary, 1622 thermal wells produce hot water for direct heat utilization. In addition, many abandoned oil and gas wells could be converted to geothermal energy production. In Hungary, district...

Although Hungary has favorable natural conditions for geothermal energy production, geothermal still plays a disproportionately weak role in the Hungarian energy market. Any remedy would require a thoughtful, comprehensive and long-term national plan for the expansion of existing geothermal systems and the development of new geothermal systems, tog...

The presentaion gives a broad introduction to geothermal topics, and will also cover the electricity production and direct-heat application as they apply to ground source heat pump system. What is geothermal energy? What is the historical background of geothermal energy? We will review geothermal activities worldwide, covering these main elements o...

The purpose of hydraulic fracturing is to stimulate the well so as to significantly improve its performance. To achieve this, a fracture is created, which is then propped open with a propping agent. The success of this process depends largely on the fracture conductivity, which is the product of the fracture width and the apparent permeability of t...

Hungary, like other eastern European countries, has suffered from an energy deficit for the past several years. Energy consumption exceeds energy production, and the country remains dependent on mostly imported fossil fuels such as oil and gas. Renewable energy usage is mostly limited to hydro and solar power generation. Government, industry and ac...

Hungary, like other eastern European countries, has suffered from an energy deficit for the past several years. Energy consumption exceeds energy production, and the country remains dependent on mostly imported fossil fuels such as oil and gas. Renewable energy usage is mostly limited to hydro and solar power generation. Government, industry and ac...

Hungary's excellent geothermal potential is well-known. Based on the 2016 Geothermal Atlas of Hungary, 1622 thermal wells produce hot water for direct heat utilization. The atlas also showed that many abandoned oil and gas wells were good possible sources of geothermal energy. This paper investigates the suitability of abandoned wells in Hungary fo...

Submersible pumps are used to enhance the production of hot water wells. The energy transfer process is treated assuming unsteady flow of inviscid fluid. Theoretical and performance head curves are studied. Cavitation and its measurement is analyzed.

The basic equations of fluid mechanics and thermodynamics are mathematical expressions of the fundamental axioms of the continuum theory. These are accepted as self-evident as a result of experiments in the physical world. In engineering, the most important task is to predict the way in which the matter responds to the external effect of its surrou...

Flow and heat transfer are studied in gathering pipelines of geothermal fields. The basic equations of fluid mechanics are reduced for one-dimensional form. Equation of motion of turbulent flow in pipes is solved by Kármán's method, from which different friction factor formulas are obtained for head loss calculations. Flow patterns of two-phase wat...

The most important interaction between a geothermal reservoir and its surroundings is heat transfer. The internal energy supply of a reservoir is mostly heat conduction across the impervious homogenous bedrocks of beneath it. This process is described by the differential equation of heat conduction. Particular cases are studied: steady on dimension...

Mechanical properties of porous media are summed up briefly in this chapter. Description of flow through porous media dates back to Darcy's classical experiment. For greater generality, it is expressed as a differential equation introducing the local seepage velocity field. Further generalization is the so-called complex continuum model in which co...

The knowledge and use of geothermal energy have a long history. The primary source of geothermal energy is the decay of radioactive elements. This energy is stored in the high temperature region of the Earth's crust, mantle, and core. From an engineering point of view, only the upper region of the crust has practical importance. Terrestrial heat-fl...

In this chapter, incompressible steady flows are considered. The velocity potential and the stream function are satisfied the Cauchy–Riemann equations. There are the real and imaginary parts of an analytic complex potential function. Knowing the complex potential, the conjugate velocity field, the streamline pattern, and the pressure distribution c...

A small fractured geothermal reservoir is investigated wherein a doublet is used to supply energy for a pilot power plant. The effect of the injection on the reservoir temperature is a cooled region from the injection well propagating toward the production well. The distance between the wells is the same order of magnitude as the lateral extent of...

Several changes of the state of wet steam are studied and represented on the T–s (temperature–entropy) diagram. The archetype of all power cycles is the Clausius–Rankine cycle. The energy conversion from thermal to mechanical energy occurs in the steam turbines. Different types of geothermal power plants are introduced; single flash, dry steam, and...

In the 1970s an important copper ore mine was implemented in Recsk, Northern Hungary. Unfortunately, as soon as the roadways were finished the activities were suspended, because of the decreasing price of copper in the international market. The mine became abandoned, and the roadways and shafts were flooded by mine water. The abandoned mine has a s...

The geothermal reservoir and its producing well form a serially connected synergetic flow system. There is a radially-inward Darcy flow toward the well in the reservoir, and a turbulent upflow through the tubing. The pressure losses of the two flows are added. The pressure energy of the undisturbed reservoir actuates this motion, providing the requ...

During production, the upflowing geothermal fluid provides a source of heat to the surrounding rock. The reason for this phenomenon is that temperature of fluid is higher than the rock around the well. This temperature inhomogeneity induces a radial heat flux from the well toward the rock. As production continues, heat transfer causes a gradual ris...

Geothermal reservoirs are studied in their undisturbed natural state. First the hydrostatic state is investigated, which is valid invariably for both porous and fractured reservoirs. The compaction of a porous sedimentary reservoir induces the natural movement of the pore fluid. Because of the flow resistance, a slight overpressure is developed. Im...

A serious field accident happened in Southeastern Hungary during the recovery of a deep, over-pressured, high-enthalpy geothermal reservoir, causing severe environmental damage. A heavy steam blowout occurred under unique conditions. The hydrodynamic and thermodynamic reconstruction of the blowout offers an explanation for certain non-trivial obser...

Flow and heat transfer have paramount importance during any drilling operations. Drilling fluid circulates in the boreholes flowing down through the drill pipe and up through the annulus. This flow disturbs the natural geothermal temperature distribution, inducing a complex heat transfer process between the circulating fluid and the surrounding roc...

Deep borehole heat exchangers are an environmentally advantageous way for geothermal energy production. The weakness of this proposed production technology is the moderate temperature of the outflowing water and the relatively low thermal power. During the initial period of the operation both the temperature and the power have a higher value, but t...

Hungary's excellent geothermal potential is well-known. Traditionally. most of the country's thermal water has been used for spas. Of the geothermal energy production most is used as a direct heat supply to heat housing projects and businesses. As yet there is no operational geothermal power-plant in Hungary. Neither is the market for ground-source...

Lecture on different geothermal topics:Geothermal among renewable energies, What is geothermal energy, hydrothermal - petrothermal geothermal reservoirs, Geothermal power plants, Geothermal direct uses, Ground Source Heat Pumps.

Geothermal education at the University of Miskolc in Hungary began in the 60s as a one-semester course. It was based on the standard reservoir-engineering and drilling curricula for petroleum engineers. In 2008, a more extensive postgraduate program was founded. This 4-semester Geothermal Engineering program covers twenty curricula topics. In 2012...

Flow and Heat Transfer in Geothermal Systems: Basic Equations for Description and Modeling Geothermal Phenomena and Technologies is the ideal reference for research in geothermal systems and alternative energy sources. Written for a wide variety of users, including geologists, geophysicists, hydro-geologists, and engineers, it offers a practical fr...

Flow and Heat Transfer in Geothermal Systems: Basic Equations for Description and Modeling Geothermal Phenomena and Technologies is the ideal reference for research in geothermal systems and alternative energy sources. Written for a wide variety of users, including geologists, geophysicists, hydro-geologists, and engineers, it offers a practical fr...

Hungary's excellent geothermal potential is well-known. Traditionally, the country's geothermal energy production was used for direct heat supply, with most of the thermal water used in spas. As yet, there is no developed ground-source heat-pump market or operational geothermal power-plant in Hungary. There are many current projects being prepared....

The University of Miskolc is the only institution in Hungary to offer Geothermal Engineering programs. It has done so since 2008, with a 4-semester program that covers twenty curricula topics. In this program, students can receive the equivalent of a B.S. or an M.S. in Geothermal Engineering. The university won a prestigious 2012 EU competition to...

Hungary has shown a considerable increase in geothermal district heating during the last few years, which is mainly due to 2 new large projects (Miskolc and Győr). Geothermal district-heating and thermal-water heating cascade systems are available in 21 towns representing about 210 MW th installed capacity and 350 GWh th /y annual production. Indiv...

A small post-industrial town is located in Borsod-Abaúj-Zemplén County, in NE Hungary. It lies in the Sajó river valley, 20 km (12 mi) from the county capital, Miskolc. The town became economically more important around 1850, when its first coal mine opened. The Socialist era (1950-1970) further stressed the importance of coal mining, but after Hun...

Pressure reduction is necessary between high-pressure natural gas transporting pipelines and low pressure distributing networks. Pressure reduction requires pre-heating the gas to compensate for the Joule-Thomson effect. Gas fired boilers will be replaced by geothermal heat pumps at more than 400 Hungarian gas pressure reduction stations (GPRS). Th...

This is an introductory graduate course covering the natural conditions, production and utilization, environmental impact of geothermal energy. The purpose of this course is to provide you with a broad understanding of these topics and their history, which will prove useful in other courses, your individual research, reading of the literature, and...

The University of Miskolc is the only institution in Hungary which offers Geothermal Engineering programs, and has done so since 2008. This 4-semester program covers twenty curricula topics. Its students can receive the equivalent of a B.S. or an M.S. in Geothermal Engineering. In 2012 the university won an EU competition to continue developing geo...

Hungary's excellent geothermal potential is well-known. Traditionally, the country's geothermal energy production was used for direct heat supply, with most of the thermal water used in spas. As yet, there is no developed ground-source heat-pump market or operational geothermal power-plant in Hungary. There are many current projects being prepared....

It is well known that Hungary, Australia and Colorado (U.S.) all have excellent geothermal potential. In Hungary, the most important tourist attractions are geothermal spas. Thermal water is widely used not just for well-being, but for medical treatments as well. These thermal waters are highly appreciated by the entire nation. Although Australia c...

Natural conditions in Hungary are very favorable for geothermal energy production and utilization. The anomalously high terrestrial heat flow (~0.09 W/m 2), the high geothermal gradient (~0.05 o C/m), and the vast expanses of deep aquifers form an important geothermal resource. The Pannonian Basin is encircled by the Carpathian Mountains. The Earth...

Kazincbarcika is a small post-industrial town of about 28,000 inhabitants, located in Borsod-Abaúj-Zemplén County, in NE Hungary. It lies in the Sajó river valley, 20 km (12 mi) from the county capital, Miskolc. Kazincbarcika became economically more important around 1850, when its first coal mine opened. The Socialist era (1950-1970) further stres...

There are different ways to define geothermal potential. At its simplest, geothermal potential is the yearly amount of recoverable geothermal energy. Another more specific definition limits geothermal potential to the recoverable energy produced by existing facilities operating continuously during a year. Yet another definition views geothermal pot...

In the Pannonian Basin, the Earth's crust is much shallower than the European average depth. This is largely a result of sub-crustal erosion. The Pannonian basin, which over time sank and was filled with tertiary sediments, has an average thickness of only about 23km. The sedimentary layers which cover it have weak thermal conductivity, on the aver...

It is well known that in the Pannonian Basin the Earth's crust is shallower and thinner than the continental average in Europe. After sub-crustal erosion sank and thinned the Pannonian basin, it was filled with tertiary sediment. The basin is now only about 23km thick. Its sedimentary layers have weak thermal conductivity, averaging about 2W/m, wit...

ISSN 2063-6997

In the '70s an important copper ore mine was implemented in Recsk Northern Hungary. Unfortunately as soon as the driving of the roadways have finished the activities had been suspended, because the decreasing price of the copper in the international market. The mine became abandoned, roadways and the shafts were flooded by mine water. The abandoned...

A small fractured geothermal reservoir is investigated wherein a doublet is used to supply energy for a pilot power plant. The effect of the injection on the reservoir temperature is a cooled region from the injection well propagating toward the production well. The distance between the wells is the same order of magnitude as lateral extent of the...

Hungary has decided to implement its first geothermal pilot power plant for electricity production. The site chosen is in South-West- Hungary and is positioned on a fractured limestone reservoir. The reservoir's depth is about 3000m and the temperature is 142 o C. Two existing petroleum- prospecting dry holes were chosen to implement a doublet for...

The Hungarian petroleum industry has always participated in the utilization of favourable geothermal conditions in the country. Most of the Hungarian geothermal wells were drilled by the MOL Ltd. as CH prospect holes. Accordingly, the field of geothermics belonged to the petroleum engineering, although marginally. It was therefore a surprise to hea...

Deep borehole heat exchangers are an environmentally advantageous way for geothermal energy production. The weakness of this proposed production technology is the moderate temperature of the outflowing water and the relatively low thermal power. During the initial period of the operation both the temperature and the power has a higher value, but th...

In the '70s an important copper ore mine was implemented in Recsk, Northern Hungary. Unfortunately as soon as the use of the roadways, were finished the activities were suspended, because the decreasing price of the copper on the international market. The mine then was abandoned the roadways and the shafts were flooded by mine water. The abandoned...

The utilization of geothermal energy has a long tradition in Hungary. When the present economic recession in the country ends in the near future, geothermal energy will surely play an increasing role in the energy supply. The paper shortly reviews the history of geothermal power use and discusses the present state of geothermal energy production in...

Deep borehole heat exchangers are an environmentally favorable way for geothermal energy production. The weakness of this proposed production technology is the moderate temperature of the outflowing water and the relatively low thermal power. The impact of the bottom-hole depth and the heat conductivity of the surrounding rock are also considered....

Between two wells in a fractured limestone geothermal reservoir the flow was investigated by two different methods in order to characterize tracer transport phenomena. The knowledge of reliable tracer transport simulation is a key issue to derive the petrophysical properties of geothermal reservoirs. In the first simulation the flow was considered...

It may reasonably be clained that geothermal energy production would be environmentally more acceptable than most other forms of energy production. From this aspect a closed-loop system seems to be especially advantageous. Hungarian Plain is full of unsuccessible drillholes for petroleum fluids. These dry holes can be utilized as underground geothe...

The floor of the entrance tunnel to an underground waste deposit system in Hungary is exposed to frost and icing in winter. This is rather dangerous for the heavy vehicle traffic. To avoid this danger, a floor deicing system was installed. This consists of a heating grid system placed in the floor of the tunnel entrance section. Initially, a fuel o...

In the '70s an important copper ore mine was implemented in Recsk Northern Hungary. Unfortunately as soon as the driving of the roadways have finished the activities had been suspended, because the decreasing price of the copper in the international market. The mine became abandoned, roadways and the shafts were flooded by mine water. The abandoned...

A hévízkutakban áramló forró víz hőmérséklet eloszlásának meghatározására számítási eljárást és az azt végrehajtó számítógépi programot dolgoztunk ki. Különösen jelentős szerepe van a hőmérséklet eloszlás alakulásában három változónak. Ezek a térfogatáram, a kút, termelésbe állítása óta eltelt időtartam, valamint a geotermikus gradiens. Megvizsgált...