Geothermal development in Hungary—country update report 2000–2002

This paper describes the status of geothermal energy utilization—direct use—in Hungary, with emphasis on developments between 2000 and 2002. The level of utilization of geothermal energy in the world increased in this period and geothermal energy was the leading producer, with 70% of the total electricity production, of all the renewable energy sources (wind, solar, geothermal and tidal), followed by wind energy at 28%. The current cost of direct heat use from biomass is 1–5 US¢/kWh, geothermal 0.5–5 US¢/kWh and solar heating 3–20 US¢/kWh. The data relative to direct use in Hungary decreased in this period and the contribution of geothermal energy to the energy balance of Hungary, despite significant proven reserves (with reinjection) of 380 million m³/year, with a heat content of 63.5 PJ/a at ΔT=40 °C, remained very low (0.25%). Despite the fact that geothermal fluids with temperatures at the surface higher than 100 °C are available, no electricity has been generated. As of 31 December 2002, the geothermal capacity utilised in direct applications in Hungary is estimated to be 324.5 MW_t and to produce 2804 TJ/year. Geothermal heat pumps represent about 4.0 MW_t of this installed capacity. The quantity of thermal water produced for direct uses in 2002 was approximately 22 million m³, with an average utilization temperature of 31 °C. The main consumer of geothermal energy is agriculture (68% of the total geothermal heat dedicated to direct uses). The geothermal water is used only in five spas for space heating and sanitary hot water (SHW), although there are 260 spas in the country, and the thermal water produced has an average surface temperature of 68 °C. The total heat capacity installed in the spas is approximately 1250 MW_t; this is not provided by geothermal but could be, i.e., geothermal could provide more than three times the geothermal capacity utilized in direct uses by 31 December 2002 (324.5 MW_t).     

Global Renewable Energy Resources

Renewable energy sources (RES) supply 14% of the total world energy demand. RES are biomass, hydropower, geothermal, solar, wind, and marine energies. The renewables are the primary, domestic and clean or inexhaustible energy resources. The percentage share of biomass was 62.1% of total renewable energy sources in 1995. Large-scale hydropower supplies 20 percent of global electricity. Wind power in coastal and other windy regions is promising as well.     

The technical,geographical, and economic feasibility for solar energy to supply the energy needs of the US

So far, solar energy has been viewed as only a minor contributor in the energy mixture of the US due to cost and intermittency constraints. However, recent drastic cost reductions in the production of photovoltaics (PV) pave the way for enabling this technology to become cost competitive with fossil fuel energy generation. We show that with the right incentives, cost competitiveness with grid prices in the US (e.g., 6–10 US¢/kWh) can be attained by 2020. The intermittency problem is solved by integrating PV with compressed air energy storage (CAES) and by extending the thermal storage capability in concentrated solar power (CSP). We used hourly load data for the entire US and 45-year solar irradiation data from the southwest region of the US, to simulate the CAES storage requirements, under worst weather conditions. Based on expected improvements of established, commercially available PV, CSP, and CAES technologies, we show that solar energy has the technical, geographical, and economic potential to supply 69% of the total electricity needs and 35% of the total (electricity and fuel) energy needs of the US by 2050. When we extend our scenario to 2100, solar energy supplies over 90%, and together with other renewables, 100% of the total US energy demand with a corresponding 92% reduction in energy-related carbon dioxide emissions compared to the 2005 levels.     

Assessment of renewable energy reserves in Taiwan

Since Taiwan imports more than 99% of energy supply from foreign countries, energy security has always been the first priority for government to formulate energy policy. The development of renewable energy not only contributes to the independence of energy supply, but also achieves benefits of economic development and environmental protection. Based upon information available to public, the present paper reassesses reserves of various renewable energies in Taiwan. The assessment includes seven kinds of renewable energies, namely, solar energy, wind power, biomass energy, wave energy, tidal energy, geothermal energy and hydropower, which are all commercialized and matured in terms of current technologies. Other renewable energies, which have not proven as matured as the aforementioned ones, are only assessed preliminarily in this paper, such as second generation of biomass, deep geothermal energy, the Kuroshio power generation and ocean thermal energy conversion.According to the estimation of this paper, the reserve of wind energy, up to 29.9 kWh/d/p (i.e., kWh per day per person), is the largest one among seven kinds of renewable energies in Taiwan, followed by 24.27 kWh/d/p of solar energy, 4.55 kWh/d/p of biomass, 4.58 kWh/d/p of ocean energy, 0.67 kWh/d/p of geothermal energy and 16.79 kWh/d/p of hydropower. If regarding biomass as a primary energy, and assuming 40% being the average efficiency to convert primary energy into electricity, the total power of the seven kinds of renewable energy reserves is about 78.03 kWh/d/p, which is equal to 2.75 times of 28.35 kWh/d/p of national power generation in 2008. If the reserves of 54.93 kWh/d/p estimated from other four kinds of renewable energies that have not technically matured yet are also taken into account, it will result that the reserves of renewable energy in Taiwan can be quite abundant.Although the results of the assessment point out that Taiwan has abundant renewable energy resources, the four inherent shortcomings – low energy density, high cost of power generation, instability of power supply, and current cost of renewable energy being still higher than that of fossil energy – have to be overcome first, before renewable energy is actually formed as a main component in national energy mix. The measures executed by government to break through these barriers further include the upgrade of the technological level, the formulation of the necessary policies, and the work together from all levels for the overall promotion.     

The feasibility of using geothermal energy in hydrogen production

A feasibility study exploring the use of geothermal energy in hydrogen production is presented. It is possible to use a thermal energy to supply heat for high temperature electrolysis and thereby substitute a part of the relatively expensive electricity needed. A newly developed HOT ELLY high temperature steam electrolysis process operates at 800 – 1000°C. Geothermal fluid is used to heat fresh water up to 200°C steam. The steam is further heated to 900°C by utilising heat produced within the electrolyser. The electrical power of this process is reduced from 4.6 kWh per normalised cubic meter of hydrogen (kWh/Nm³ H₂) for conventional process to 3.2 kWh/Nm³ H₂ for the HOT ELLY process implying electrical energy reduction of 29.5%. The geothermal energy needed in the process is 0.5 kWh/Nm³ H₂. Price of geothermal energy is approximately 8–10% of electrical energy and therefore a substantial reduction of production cost of hydrogen can be achieved this way. It will be shown that using HOT ELLY process with geothermal steam at 200°C reduces the production cost by approximately 19%.     

Hydropower for sustainable water and energy development

Turkey has a total gross hydropower potential of 433 GWh/year, but only 125 GWh/year of the total hydroelectric potential of Turkey can be economically used. By the commissioning of new hydropower plants, which are under construction, 36% of the economically usable potential of the country would be tapped. Turkey presently has considerable renewable energy sources. The most important renewable sources are hydropower, biomass, geothermal, solar and wind. Turkey's geographical location has several advantages for extensive use of most of these renewable energy sources. Over the last two decades, global electricity production has more than doubled and electricity demand is rising rapidly around the world as economic development spreads to emerging economies. Not only has electricity demand increased significantly, it is the fastest growing end-use of energy. Therefore, technical, economic and environmental benefits of hydroelectric power make it an important contributor to the future world energy mix, particularly in the developing countries.     

Geothermal energy technology and current status: an overview

Geothermal energy is the energy contained as heat in the Earth’s interior. This overview describes the internal structure of the Earth together with the heat transfer mechanisms inside mantle and crust. It also shows the location of geothermal fields on specific areas of the Earth. The Earth’s heat flow and geothermal gradient are defined, as well as the types of geothermal fields, the geologic environment of geothermal energy, and the methods of exploration for geothermal resources including drilling and resource assessment.Geothermal energy, as natural steam and hot water, has been exploited for decades to generate electricity, and both in space heating and industrial processes. The geothermal electrical installed capacity in the world is 7974 MW_e (year 2000), and the electrical energy generated is 49.3 billion kWh/year, representing 0.3 % of the world total electrical energy which was 15,342 billion kWh in 2000. In developing countries, where total installed electrical power is still low, geothermal energy can play a significant role: in the Philippines 21% of electricity comes from geothermal steam, 20% in El Salvador, 17% in Nicaragua, 10% in Costa Rica and 8% in Kenya. Electricity is produced with an efficiency of 10–17%. The geothermal kWh is generally cost-competitive with conventional sources of energy, in the range 2–10 UScents/kWh, and the geothermal electrical capacity installed in the world (1998) was 1/5 of that from biomass, but comparable with that from wind sources.The thermal capacity in non-electrical uses (greenhouses, aquaculture, district heating, industrial processes) is 15,14 MW_t (year 2000). Financial investments in geothermal electrical and non-electrical uses world-wide in the period 1973–1992 were estimated at about US$22,000 million. Present technology makes it possible to control the environmental impact of geothermal exploitation, and an effective and easily implemented policy to encourage geothermal energy development, and the abatement of carbon dioxide emissions would take advantage from the imposition of a carbon tax. The future use of geothermal energy from advanced technologies such as the exploitation of hot dry rock/hot wet rock systems, magma bodies and geopressured reservoirs, is briefly discussed. While the viability of hot dry rock technology has been proven, research and development are still necessary for the other two sources. A brief discussion on training of specialists, geothermal literature, on-line information, and geothermal associations concludes the review.     

Renewable energy sources in Turkey for climate change mitigation and energy sustainability

In Turkey, there is a much more potential for renewables, but represent about 37% of total energy production and 10% of total energy consumption. This share is not enough for the country and the governments should be increase to this situation. Renewable energy technologies of wind, biomass, hydropower, geothermal, solar thermal and photovoltaics are finally showing maturity and the ultimate promise of cost competitiveness. With respect to global environmental issues, Turkey's carbon dioxide emissions have grown along with its energy consumption. States have played a leading role in protecting the environment by reducing emissions of greenhouse gases. In this regard, renewable energy resources appear to be the one of the most efficient and effective solutions for clean and sustainable energy development in Turkey. Turkey's geographical location has several advantages for extensive use of most of these renewable energy sources. Certain policy interventions could have a dramatic impact on shaping the relationship between geological, geographic and climatic conditions and energy production. This study shows that there is enough renewable energy potential in Turkey for fuels and electricity. Especially hydropower and biomass are very well.     

Electricty generation from woody biomass fuels compared with other renewable energy options

The future New Zealand biomass resource from exotic plantation forest arisings could supply 970 GWh/year by the year 2002. Associated wood processing residues could supply 280 GWh/year. Purpose grown fuelwood plantations could supply 2060 GWh/year with potential to rise to 10,000 GWh/year by 2012.Currently the annual electricity demand is around 30,000 GWh 70% of which is generated by hydro power. Natural gas, a resource with estimated reserves of only approximately 14 years currently supplies 25% of generating capacity. This paper describes how part replacement of gas by biomass could be a feasible proposition for the future.Life cycle cost analyses showed electricity could be generated from arisings for (US)4.8–6 c/kWh; from residues for (US)2.4–4.8 c/kWh; and from plantations for (US)4.8–7.2 c/kWh. For comparison the current retail electricity price is around (US)4–5.5 c/kWh and estimates for wind power generation range from (US)5–10 c/kWh. Future hydropower schemes will generate power between (US)4–9 c/kWh depending on site suitability.     

Renewable energy in Taiwan: Its developing status and strategy

With limited indigenous conventional energy resources, Taiwan imports over 97% of its energy supply from foreign countries, mostly from the Middle East. Developing independent renewable energy resources is thus of priority concern for the Taiwanese government. A medium subtropical island surrounded by the Pacific Ocean, Taiwan has enormous potential to develop various renewable energies, such as solar energy, biomass energy, wind power, geothermal energy, hydropower, etc. However, owing to the importance of conventional fossil energy in generating exceptionally cheap electricity, renewable energy has not yet fully developed in Taiwan, resulting from a lack of market competition. Consequently, numerous promotional and subsidy programs have recently been proclaimed by the Taiwanese government, focused on the development of various renewables. This study reviews the achievements, polices and future plans in this area.     

Thermoeconomic analysis and artificial neural network based genetic algorithm optimization of geothermal and solar energy assisted hydrogen and power generation

The study aims to optimize the geothermal and solar-assisted sustainable energy and hydrogen production system by considering the genetic algorithm. The study will be useful by integrating hydrogen as an energy storage unit to bring sustainability to smart grid systems. Using the Artificial Neural Network (ANN) based Genetic Algorithm (GA) optimization technique in the study will ensure that the system is constantly studied in the most suitable under different climatic and operating conditions, including unit product cost and the plant's power output. The water temperature of the Afyon Geothermal Power Plant varies between 70 and 130 °C, and its mass flow rate varies between 70 and 150 kg/s. In addition, the solar radiation varies between 300 and 1000 W/m² for different periods. The net power generated from the region's geothermal and solar energy-supported system is calculated as 2900 kW. If all of this produced power is used for hydrogen production in the electrolysis unit, 0.0185 kg/s hydrogen can be produced. The results indicated that the overall energy and exergy efficiencies of the integrated system are 4.97% and 16.0%, respectively. The cost of electricity generated in the combined geothermal and solar power plant is 0.027 $/kWh if the electricity is directly supplied to the grid and used. The optimized cost of hydrogen produced using the electricity produced in geothermal and solar power plants in the electrolysis unit is calculated as 1.576 $/kg H₂. The optimized unit cost of electricity produced due to hydrogen in the fuel cell is calculated as 0.091 $/kWh.     

Turkey's Renewable Energy Facilities in the Near Future

In this work, renewable energy facilities of Turkey were investigated. Electricity is mainly produced by thermal power plants, consuming coal, lignite, natural gas, fuel oil and geothermal energy, and hydro power plants in Turkey. Turkey has no large oil and gas reserves. The main indigenous energy resources are lignite, hydro and biomass. Turkey has to adopt new, long-term energy strategies to reduce the share of fossil fuels in primary energy consumption. For these reasons, the development and use of renewable energy sources and technologies are increasingly becoming vital for sustainable economic development of Turkey. The most significant developments in renewable production are observed hydropower and geothermal energy production. Renewable electricity facilities mainly include electricity from biomass, hydropower, geothermal, and wind and solar energy sources. Biomass cogeneration is a promising method for production bioelectricity.     

Present status and potential role of geothermal energy in the world

Geothermal energy has come of age as an energy source. It is found in most parts of the world and is harnessed by conventional technology. Commercial production on the scale of hundreds of MW has been undertaken for over three decades both for electricity generation and direct utilization. Some 80 countries have identified geothermal resources, and about 50 have quantifiable geothermal utilization at present. Electricity is produced from geothermal in 21 countries (total production 38 TWh/a) and direct application is recorded in 35 countries (34 TWh/a). Geothermal electricity production is equally common in industrialized and developing countries, but plays a more important role in the latter. Apart from China, direct use is mainly in the industrialized countries and Central and Eastern Europe. Most of the developing countries as well as Central and Eastern European countries still lack trained manpower, but there is a surplus in many industrialized countries. During 1973–1992, investments in geothermal energy amounted to approximately 22 billion USD. The large share of the private sector in the investments shows its confidence in this energy source. Data presented in the WEC Survey of Energy Resources 1995 on the “new renewables” (geothermal, solar, wind, and tidal energy) shows that geothermal has the largest installed electrical capacity (61%) and electricity production (81%) in the world of these four sources.     

Fast market penetration of energy technologies in retrospect with application to clean energy futures

The fast penetration of energy technologies in the past was analyzed and applied to investigate the prospects of new energy technologies. The results show that single energy sources have obtained quite a dominant position in the past. In the USA, at one time both oil and coal each represented over half of all the yearly additions to energy capacity for more than half a century and reached a dominant position in overall energy production. Oil showed a similar dominance on a global scale. For two decades nuclear power represented one third of all the new electricity added worldwide and over 60% in the countries possessing nuclear power. In some countries nuclear grew to around half of all electricity in less than just 10 years. Applying these empirical observations to new renewables and assuming similar growth conditions as for the old technologies, the share of renewable electricity could grow from its present 19% to 60% by 2050, which would drop the baseline CO₂ emissions by 27%. The share of new renewables of all electricity would come up to 42%. The rate of adoption of these new technologies would not exceed that of oil or nuclear in the past, but they would need to dominate new electricity investments from 2030 onwards. A hypothetical fast-track case for solar photovoltaics, assuming an expansion similar to that seen in the case of nuclear and oil, would lead to a 20–25% share of all electricity in 2050. An important observation is that the fast and high penetration of energy technologies implies, in most cases, a full lock-in into these, requiring a preferential position regarding investments and a favorable long-term policy framework.     

Global energy efficiency improvement in the long term: a demand- and supply-side perspective

This study assessed technical potentials for energy efficiency improvement in 2050 in a global context. The reference scenario is based on the World Energy Outlook of the International Energy Agency 2007 edition and assumptions regarding gross domestic product developments after 2030. In the reference scenario, worldwide final energy demand almost doubles from 293 EJ in 2005 to 571 EJ in 2050 and primary energy supply increases from 439 EJ in 2005 to 867 EJ in 2050 (excluding non-energy use). It is estimated that, by exploiting the technical potential for energy efficiency improvement in energy demand sectors, this growth can be limited to 8% or 317 EJ final energy demand and 473 EJ primary energy supply in 2050. This corresponds to a potential for demand-side energy efficiency improvement of 44% in 2050, in comparison to reference energy use. In addition, a potential exists for improving energy efficiency in the transformation sector. In 2005, as much as 33% of primary energy supply is lost in the transformation and distribution of primary energy. It is estimated that this share can be reduced to 19% in 2050 by, e.g. improving energy efficiency of fossil-fired power generation (assuming no changes in the fuel mix for power generation). Including the potential for energy efficiency improvement in energy demand sectors, total primary energy supply would then decrease by 10% from 439 EJ in 2005 to 393 EJ in 2050. This contributes to a total potential for energy efficiency improvement of 55% in 2050 in comparison to reference primary energy supply.     

Alternative Electricity Generation Opportunities

Abstract

In this article, comparing four renewable energy sources shows 70% of the electricity generated by the four to come from geothermal with only 42% of the total installed capacity. Wind energy contributes 27% of the electricity, but has 52% of the installed capacity. Solar energy produces 2% of the electricity and tidal energy 1%. Biomass constitutes 93% of the total direct heat production from renewables, geothermal 5%, and solar heating 2%. Conventional fossil energy will not be enough to meet the continuously increasing need for energy in the future. In this case, renewable energy sources will become important. Alternative energy sources are increasing need for energy in the future.     

Wood gasification integrated with fuel cells

Techno-economic assessments of systems which integrate biomass gasification with fuel cell modules (molten carbonate or phosphoric acid) for electricity generation are presented. The wood-fired Phosphoric Acid Fuel Cell was found to be suitable where high heat/electricity values were required, but had low electrical efficiency. Electrical efficiencies of 13–17% are typical for these systems, as are Break-even Electricity Selling Prices (BESPs) of 10–20 p/kWh and specific investments of around £3000–£7500/kWe. This technology is unlikely to be considered for further development as an electricity generation system.The wood-fired Molten Carbonate Fuel Cell was found to be quite efficient and suitable for small-scale electricity generation purposes. Electrical efficiencies of 25–28% are typical for these systems, as are Break-even Electricity Selling Prices of 6–12 p/kWh and specific investments of around £2000–£5000/kWe. This technology could be considered for further development in the future, if the lifetime and capital costs of molten carbonate fuel cells can be improved. The problems in assessing future capital costs makes the economic viability of such systems difficult to determine.     

The potential for renewable energy in industrial applications

To date, insufficient attention has been paid to the potential of renewable energy resources in industrial applications. Our analysis suggests that up to 21% of final energy demand and feedstock-use in the manufacturing industry sector could be of renewable origin by 2050, a five-fold increase over current levels in absolute terms. This estimate is considerably higher than other recent global scenario studies. In addition, if a 50% share of renewables in power generation is assumed, the share of direct and indirect renewable energy use rises to 31% in 2050. Our analysis further suggests that bioenergy and biofeedstocks can constitute three-quarters of the direct renewables use in this sector by 2050. The remainder is roughly evenly divided between solar heating and heat pumps. The potential for solar cooling is considered to be limited.While low-temperature solar process heat can reach cost-effectiveness today in locations with good insolation, some bioenergy applications will require a CO₂ price even on the longer term. Biomass feedstock for synthetic organic materials will require a CO₂ price up to USD 100/t CO₂, or even more if embodied carbon is not considered properly in CO₂ accounts. Future fossil fuel prices and bioenergy prices in addition to the development of feedstock commodity markets for biomass will be critical. Decision makers are recommended to pay more attention to the potential for renewables in industry. Finally, we propose the development of a detailed technology roadmap to explore this potential further and discuss key issues that need to be elaborated in such a framework.     

Importance of geothermal energy and its environmental effects in Turkey

Geothermal energy, a relatively benign energy source when compared with other energy sources due to reduction in greenhouse gas emissions, is used for electricity generation and direct utilization. Turkey has a place among the first seven countries in the world in the abundance of geothermal resources, but it has only used about 4% of its potential. The paper presents the status of energy needs and renewables, potential, utilization and the importance of geothermal energy in Turkey. It also gives a comparison between geothermal energy and other energy sources regarding environmental issues. It is estimated that if the geothermal heating potential alone in Turkey is used, 5 million residences will be heated and as a result, releases of 48 million ton/year CO₂ emissions into the atmosphere will be prevented. In addition to this, if the other geothermal potential (i.e. electricity) is used it will provide considerable environmental benefits. Therefore, it is expected that geothermal energy development will significantly speed up in the future.     

Renewable energy resource potential in Pakistan

Pakistan energy situation is seriously troubling today due to lack of careful planning and implementation of its energy policies. To avoid the worse situation in the years ahead, the country will have to exploit its huge natural renewable resource. In this paper a review is being presented about renewable energy resource potential available in the country to be exploited for useful and consistent energy supplies. On average solar global insolation 5–7 kWh/m²/day, wind speed 5–7.5 m/s, Biogas 14 million m³/day, microhydel more than 600 MW (for small units) with persistency factor of more than 80% over a year exist in the country. Solar and wind maps are presented along with identification of hot spring sites as resource of geothermal energy. The research results presented in this paper are not only useful for government policy makers, executing agencies but also for private sector national and international agencies and stake holders who want to invest in Pakistan for renewable energy projects or business.