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Geotermalna energija je toplinska energija Zemlje koja predstavlja jedan od najvažnijih obnovljivih izvora energije. Ograničenost zaliha fosilnih goriva, stalni rast cijena nafte, težnja za manjom energetskom ovisnošću, nastojanja svjetskih institucija na smanjenju emisije stakleničkih plinova i tehnološki napredak, glavni su čimbenici u odlučivanju primjene obnovljivih izvora energije, posebice geotermalne energije. Geotermalni resursi su gotovo nepresušan izvor energije i čitava budućnost čovječanstva mogla bi se bazirati na korištenju geotermalnih resursa. Budući da ima veliki potencijal, u ovom diplomskom radu dat je prikaz trenutnog stanja uporabe geotermalne energije u svijetu i Republici Hrvatskoj. Također, predstavljene su sheme financijskih poticaja za većom primjenom ovog oblika obnovljivih izvora energije. Dat je prikaz pozitivnih učinaka subvencija ali su prikazani i njihovi nedostatci, i sve to na primjerima iskustava pojedinih zemalja. Istraženo je i prikazano trenutno stanje subvencioniranja primjene geotermalne energije u Republici Hrvatskoj s prijedlogom preporuka., Geothermal energy is the thermal energy of the Earth, which is one of the most important renewable energy sources. The limitations of fossil fuel reserves, steady growth in oil prices, the pursuit of lower energy dependence, the efforts of world institutions to reduce greenhouse gas emissions and technological advances, are the main factors in determining the application of renewable energy sources, especially geothermal energy. Geothermal resources are virtually inexhaustible source of energy and the whole future of humanity could be based on the use of geothermal resources. Since it has great potential, this graduate thesis provides an overview of the current state of the use of geothermal energy in the world and the Republic of Croatia. Also, presented is a scheme of financial support for the greater use of this form of renewable energy. An overview of the positive effects of subsidies as well as their weaknesses is presented, and all examples represent experiences of individual countries. The research involved and shows the current status of subsidizing the application of geothermal energy in the Republic of Croatia with the proposal of recommendations.

Geothermal is a renewable source energy that can be used directly for heating or for power production. Geothermal utilization, particularly power production, may result in some greenhouse gas (GHG) emissions. GHG emissions from geothermal power production is generally small in comparison to traditional base load thermal energy power generation facilities. This is mainly due to the fact that the large majority of installations draw their geothermal energy from geothermal reservoirs with low GHG concentrations. However, as the geothermal sector has expanded, a wider range of geothermal resources have been brought into exploitation, including geothermal systems with relatively high GHG concentrations in the reservoir fluid. There is a growing realization within the geothermal community that geothermal power plants can, in rare instances, release significant quantities GHG into the atmosphere. This interim technical note presents an overview of the current knowledge on GHG emissions from geothermal systems and geothermal power plants, and gives guidance on how to assess GHG emissions from geothermal projects when this is required, depending on their stage of development. This note identifies critical knowledge gaps and presents recommendations as to how close these gaps and proposes an interim methodology to estimate GHG emissions from geothermal projects that financing institutions, such as the World Bank, intend to support. The plan is to update this note when the methodology has been tested by application to actual projects and some of the current knowledge gaps have been closed as more information become available. This note proposes a way to estimate future emission factors for geothermal projects under development. For instance, if a pumped binary power plant is planned, the emission factor will be 0. Projects using other energy conversion technologies will result in some emissions. For projects where wells have been drilled and tested, formulas are provided to compute emission factors based on the chemical composition of the geothermal fluid and the design parameters of the power plant. For projects located in the vicinity of existing power plants in analogous geologic settings, emission factors from the existing plants can be used.

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.

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.

GEISER was a European project on understanding and mitigation of induced seismicty in geothermal operations. The project involved several European research institutions as well as industry and was funded by the European Commission within FP7. GEISER addressed a better understanding of the key parameters that control induced seismicity in response to an injection. Data from several events of induced seismicity were collected and analysed. Mechanical models were developed to understand the processes leading to induced seismicity and were combined with probabilistic seismic hazard assessment approaches to propose a new, physics based probabilistic forewarning system. This system requires the determination of a maximum acceptable seismic magnitude and its accepted probability of occurrence. The reliability of the dynamic model is based on the availability of rock physics and seismic data, with models updated from real-time monitoring. In addition to this new approach, a number of recommendations and guidelines for licensing authorities, developers and operators of geothermal projects are proposed.

GEISER was a European project on understanding and mitigation of induced seismicty in geothermal operations. The project involved several European research institutions as well as industry and was funded by the European Commission within FP7. GEISER addressed a better understanding of the key parameters that control induced seismicity in response to an injection. Data from several events of induced seismicity were collected and analysed. Mechanical models were developed to understand the processes leading to induced seismicity and were combined with probabilistic seismic hazard assessment approaches to propose a new, physics based probabilistic forewarning system. This system requires the determination of a maximum acceptable seismic magnitude and its accepted probability of occurrence. The reliability of the dynamic model is based on the availability of rock physics and seismic data, with models updated from real-time monitoring. In addition to this new approach, a number of recommendations and guidelines for licensing authorities, developers and operators of geothermal projects are proposed.

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).

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

At present, the worldwide geothermal energy production provides less than 1% of the world's energy needs but the geothermal resources confined in the first 6 km of the earth's crust are estimated to be in the fairly above 200 GW of which 50-80 GW are located in Europe. Exploring and developing at large scale untapped hydrothermal resources represent a major challenge for geothermal energy development worldwide. Several workflow processes, procedures and techniques are currently applied to locate and assess the geothermal potential in various geological contexts: sediments, volcanic, granites and metamorphic. Models and tools has been developed to forecast the performance of a green field geothermal project, but many uncertainties determine relevant risks for the investors in all the different phases of the single project and mainly in the exploration phase. The uncertainties are mainly related to the technical and economical performance (e.g. resource characteristics, the efficiency of power conversion systems, energy market conditions) but the environmental sustainability and the social acceptance might represent potential hurdles for the project development. This paper describes an innovative approach for risk assessment and mitigation applied for the exploration of green field geothermal projects. A holistic multi criteria analysis is applied to calculate the risk index of the project based on: a) resource characteristics (e.g. depth, temperature and sustainability along the whole life of the project), b) technological solution for power conversion systems (e.g. electricity and/or heat generation), c) market conditions (e.g. electricity price, tax regimes), d) the environmental and social factors (e.g. air emission, induced seismicity, natural parks). A guideline is proposed for the identification and ranking of the most promising areas suitable for sustainable geothermal project development in Europe.

The challenge for the development community is to exploit the links between energy and poverty to combat global poverty. The human scale of this challenge is huge. Today, 1.6 billion people lack access to electricity and 2.4 billion rely on traditional biomass for cooking and heating. Indoor air pollution is among leading causes of illness and death in developing countries. It leads to 2 million premature deaths a year. In 2004, the richest 20 percent of the world s population consume 58 percent of total energy, while the poorest 20 percent consume less than 4 percent. The majority of those underserved are the poor in Sub-Saharan Africa and South Asia. With increasing populations, 25 years from now, business-as-usual energy scenarios project that even after an expenditure of 16 trillion US dollars on energy investments of which half will be in developing countries, 1.4 billion people will still lack access to electricity. This is a reduction of only 200 million people from today. Over 2.6 billion people in developing countries will continue to rely on traditional forms of biomass for cooking and heating in 2030, even more than today. This scenario expects renewable energy share to increase from 2 percent to 3 percent between 2000 and 2030. Under this scenario, by 2030, the more than doubling of coal, oil and gas consumption will lead to increases in greenhouse gas emissions from the energy sector. The impacts will affect the developing countries the most, and hence rendering the poor more vulnerable. Projected impacts are increased deaths and risk of infectious disease epidemics; increased floods, mudslides and coastal and soil erosion; increased property and infrastructure damage; decreased crops, higher crop damages and a general drop in agricultural productivity.

The development of deep geothermal energy sources in Germany still faces many uncertainties and high upfront investment costs. Methodical approaches to assess the exploration risk are thus of major importance for geothermal project development. Since 2002, expert reports to quantify the exploration risk for geothermal projects in Germany were carried out. These reports served as a basis for insurance contracts covering the exploration risk. Using data from wells drilled in the meantime, the reports were evaluated and the stated probabilities compared with values actually reached.