Research on the generation of electricity from the geothermal resources in Simav region, Turkey

One of the greatest problems in using renewable energy sources is the great variability of energy level, both in the short and long term. Geothermal energy, by nature, has high availability because the source is not dependent on weather conditions, so it is among the most stable renewable energy sources. Geothermal energy has the potential to play an important role in the future energy supply of Turkey. Although Turkey has the second-highest geothermal energy potential in Europe, electricity generation from geothermal energy is rather low.This study examines the use of geothermal energy in electricity generation and investigates the applicability of the existent geothermal energy resources to electricity generation in the Kütahya–Simav region, Turkey. The binary cycle is used in the designed power plant for electricity generation from geothermal fluid in which the percentage of liquid is high and which is at lower temperature. In this power plant, R134a is chosen as the secondary fluid, whose boiling point temperature is lower than that of water, and is used instead of geothermal fluid in a second cycle. The thermal efficiency of the designed power plant is measured to be 12.93%.     

Hybrid geothermal–fossil electricity generation from low enthalpy geothermal resources: geothermal feedwater preheating in conventional power plants

Hybrid steam power plants with geothermal feedwater preheating enable the conversion of geothermal energy into electricity in countries with low enthalpy geothermal resources. In order to estimate the potential of geothermal–fossil hybrid power plants with geothermal feedwater preheating, we examine the application of this concept using the examples of two modern coal fired power plants. In addition, energy output and economic efficiency calculations will be compiled for this concept utilising the thermal water data of an existing geothermal heating installation and an experimental facility for the hot dry rock technology. The process of geothermal feedwater preheating as a means of improving performance forms both an alternative and an extension to the existing electricity generation methods based on renewable energy. Photovoltaics or wind power, for example, tend to be expensive and also unreliable due to weather uncertainties. An electricity cost of around 85 EUR/MWh appears to be attainable through the geothermal preheating concept in Central Europe. In countries with the appropriate prerequisites, this concept heralds considerable benefits in terms of efficient electricity generation and environmental protection.     

Utilities' role in deploying renewables

The aim of this paper is to review the current status and prospects of the renewable energy sources that are more suitable for the production of electricity, and to present the views of the EURE Group on the role electricity utilities could play in deploying generating plants based on these sources. In the first part of the paper, reference is made both to the renewable sources that have long been used for these purposes, such as hydro power, and to the “new” ones, particularly bioenergy, photovoltaics and wind power. Mention is also made of other technologies that have so far been less developed or can be applied only locally (e.g. geothermal energy). In the second part, the paper advises on the way utilities could contribute to renewable energy research and how they could help promoting these sources.     

Governmental policy and prospect in electricity production from renewables in Lithuania

In Lithuania, the generation of electricity is based on the nuclear energy and on the fossil fuels. After the decommissioning of Ignalina nuclear power plant in 2009, the Lithuanian Power Plant and other thermal plants will become the major sources of electricity. Consequently, the Lithuanian power sector must focus on the implementation of renewable energy projects, penetration of new technologies and on consideration of the future opportunities for renewables, and Government policy for promoting this kind of energy. Production of electricity from renewable energy is based on hydro, biomass and wind energy resources in Lithuania. Due to the typical climatic condition in Lithuania the solar photovoltaics and geothermal energy are not used for power sector. Moreover, the further development of hydropower plants is limited by environmental restrictions, therefore priority is given to wind energy development and installation of new biomass power plants. According to the requirements set out in the Directive 2001/77/EC of the European Parliament and of the Council of 27 September 2001 on the promotion of electricity produced from renewable energy sources in the internal electricity market [Official Journal L283, 33–40, 27 October 2001], 7% of gross consumption of electricity will be generated from renewable energy by 2010 in Lithuania. The aim of this paper is to show the estimation of the maximum renewable power penetration in the Lithuanian electricity sector and possible environmental impact.     

Quality uncertainty and the market for renewable energy: Evidence from German consumers

Consumers can choose from a wide range of electricity supply contracts, including green power options. Electricity produced from renewable energy involves information asymmetries. With a sample of more than 2,000 German electricity consumers, we tested the proposition of a “lemon market” for renewable energy in a discrete choice experiment. Specifically, we found that, compared to investor-owned firms, additional willingness-to-pay for renewable energy is approximately double when offered by cooperatives or municipally-owned electricity utilities. Consumers who are experienced with switching suppliers have an additional willingness-to-pay of one Eurocent per kilowatt hour for cooperatives and two Eurocents for public enterprises. The results demonstrate that organizational transformation in dynamically-changing electricity markets is not only driven by political initiatives but also by consumers' choices on the market. Public policy may reduce information asymmetries by promoting government labeling of green energy products.     

促进可再生能源市场化的省内中长期运行策略研究

针对可再生能源市场化进程的加快,结合中国电力市场建设现状,对促进可再生能源市场化消纳的省级中长期交易机制以及与现货市场的衔接问题进行研究。利用资源分布特点,提出以可再生能源消纳及常规机组合约完成进度偏差为目标的电量分解模型,针对可再生能源的不确定性,提出基于多场景集的ANFIS预测技术进行可再生能源中长期电量预测,以此为基础进行电量分解,提升可再生能源利用率;建立计及中长期合约分解电量及可再生能源出力不确定性的日前市场出清策略,保证中长期合约电量的物理执行,实现与现货市场的有序衔接。最后通过算例分析验证所提模型的有效性和实用性。     

Advanced mechanisms for the promotion of renewable energy—Models for the future evolution of the German Renewable Energy Act

The German Renewable Energy Act (EEG) has been very successful in promoting the deployment of renewable electricity technologies in Germany. The increasing share of EEG power in the generation portfolio, increasing amounts of fluctuating power generation, and the growing European integration of power markets governed by competition calls for a re-design of the EEG. In particular, a more efficient system integration and commercial integration of the EEG power is needed to, e.g. better matching feed-in to demand and avoiding stress on electricity grids. This article describes three different options to improve the EEG by providing appropriate incentives and more flexibility to the promotion mechanism and the quantitative compensation scheme without jeopardising the fast deployment of renewable energy technologies. In the “Retailer Model”, it becomes the responsibility of the end-use retailers to adapt the EEG power to the actual demand of their respective customers. The “Market Mediator Model” establishes an independent market mediator responsible to market the renewable electricity. This model is the primary choice when new market entrants are regarded as crucial for the better integration of renewable energy and enhanced competition. The “Optional Bonus Model” relies more on functioning markets since power plant operators can alternatively choose to market the generated electricity themselves with a premium on top of the market price instead of a fixed price.     

Status and outlook of China's free-carbon electricity

Global warming, increased energy demand, and tremendous air pollution are forcing China to revise its energy structure of electricity generation dominated by coal (80% of total electricity) towards low-carbon electricity. Vigorous development of carbon-free energy resources of electricity is a practical way towards low-carbon electricity in China. In this paper, we shall outline renewable power generation (hydropower, wind power, solar energy, biomass energy, nuclear power, ocean energy and geothermal) together with nuclear power for China, present a reserves assessment, the current status, and barriers for further development, and finish with an outlook towards the future. In our view, China has plenty of free-carbon energy resources to revolutionize its electricity structure and redirect it towards low-carbon electricity systems. Needed are the effective energy policies to get to the way.     

The impact of carbon capture and storage on a decarbonized German power market

The European energy policy is substantially driven by the target to reduce the CO₂-emissions significantly and to mitigate climate change. Nevertheless European power generation is still widely based on fossil fuels. The carbon capture and storage technology (CCS) could be part of an approach to achieve ambitious CO₂ reduction targets without large scale transformations of the existing energy system. In this context the paper investigates on how far the CCS-technology could play a role in the European and most notably in the German electricity generation sector. To account for all the interdependencies with the European neighboring countries, the embedding of the German electricity system is modeled using a stochastic European electricity market model (E2M2s). After modeling the European side constraints, the German electricity system is considered in detail with the stochastic German Electricity market model (GEM2s). The focus is thereby on the location of CCS plant sites, the structure of the CO₂-pipeline network and the regional distribution of storage sites. Results for three different European energy market scenarios are presented up to the year 2050. Additionally, the use of CCS with use of onshore and offshore sites is investigated.     

Green energy market development in Germany: effective public policy and emerging customer demand

This paper reviews the development of renewable energy in Germany from 1973 to 2003. It investigates the relative importance of energy policy and green power marketing in shaping the renewable energy market. More than a decade of consistent policy support for renewables under the feed-in law (StrEG) and its successor (EEG) has been an important driver for increasing renewable electricity generation to date, putting the country in a better position than most of its peers when it comes to achieving European Union targets for renewable energy. Green power marketing driven by customer demand, on the other hand, is growing, but has had limited measurable impact so far. We discuss potential intangible benefits of green power marketing and scenarios for future market development. The paper concludes with lessons that can be learned from the German case for policy design and market development in other countries.     

Potential and use of renewable energy sources in Croatia

The current share of renewable energy sources in electricity production in Croatia is very high, around 50%. Nevertheless it is expected that the share of renewables will have to rise and efficient strategies must be examined and adopted. The Croatian government has recognised the important role renewable energy sources could play in Croatian energy and electricity supply. The most important barrier for a wider deployment of renewables in energy production is their cost which is still above those of conventional energy sources. As the energy market is currently undergoing the process of liberalisation, support mechanisms that are compatible with an open market philosophy must be adopted. The characteristics of the Croatian power system, the expected consumption, growth and possible future role of renewables in energy and electricity production is presented. The current legislative framework relevant for renewables is analysed and discussed.     

Abuse of dominance and antitrust enforcement in the German electricity market

In 2008, the European Commission investigated E.ON, a large and vertically integrated electricity company, for the alleged abuse of a joint dominant position by strategically withholding generation capacity in the German wholesale electricity market. The case was settled after E.ON agreed to divest 5 GW generation capacity as well as its extra-high voltage network. We analyze the effect of these divestitures on wholesale electricity prices. Our identification strategy is based on the observation that energy suppliers have more market power during peak periods when demand is high. Therefore, a decrease in market power should lead to convergence between peak and off-peak prices, after controlling for different demand and supply conditions as well as the change in generation mix due to the expansion of renewable technologies. Using daily electricity prices for the 2006–2012 period, we find economically and statistically significant convergence effects after the settlement of the case. In a richer specification, we show that the price reductions appear to be mostly due to the divestiture of gas and coal plants, which is consistent with merit-order considerations. Additional cross-country analyses support our results.     

NGOs and green electricity

Electricity from renewable energy sources is by definition the environmental “green” product. Sales of green power are usually supported by marketing campaign images of a melting ice cap, polar bears in danger and other environmental catastrophes. Greenprices this month takes a closer look at NGOs, organisations whose task is to raise the environmental awareness of the public, and to try to understand how they position themselves today on the green electricity market. There are to date three ways by which non-governmental organisations can play a role on the market for electricity from renewable energy sources: promoting, selling and labelling green electricity.     

Renewable energy in Oman: Status and future prospects

This paper attempts to review and discuss the status and future prospects of renewable energy in Oman. Renewable energy sources like solar, wind, hydro, geothermal, and biomass have been revised. The electricity shortages and the challenges to overcome the increase in electrical demands for the near future have been discussed. The investigations found that solar, shore-wind and geothermal could play an important role in the future of renewable energy in country. Also, it is found that there is need to investigate the potential of offshore-wind, biomass, and hydro (tide, wave and ocean thermal energy). The appearance and weight of renewable energy in the higher education programs and the Oman commitment toward renewable energy have been discussed. The paper finishes with some conclusions and recommendations.     

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.     

现货市场新能源参与方式及其对市场出清价格的影响分析

在我国新一轮电力市场改革背景下,电力现货市场建设进程进一步加快.随着新能源装机的快速增长,将会对电力现货市场竞价交易带来很大影响.基于我国试点运行的现货交易机制,对现行几种新能源参与市场模式进行了分析并提出了适用于新能源快速发展阶段的市场参与机制.建立了包含新能源参与的省级日前市场机组组合模型和实时市场安全经济调度模型...     

Model‐based approach for planning renewable energy transition in a resource‐constrained electricity system—A case study from India

Globally, electricity systems are going through transitions. The contributions from renewable energy‐based power generation, both in installed capacity and electricity generation, are moving from marginal to the mainstream. India is not an exception; it is aggressively pursuing this transition by fixing steep targets for renewable capacity additions. While the cost of renewable energy sources is expected to fast reach grid parity, the policy interventions play a critical role in ramping up the efforts to support the proposed investments in renewable capacity and renewable electricity generation. In this respect, this research attempts to analyze the effectiveness of renewable energy policies such as Renewable Purchase Obligation (RPO) and Renewable Energy Certificate mechanisms in tapping the renewable energy potential in India. We propose a mixed‐integer linear programming model‐based approach to evaluate the effectiveness of the above interventions in the Indian context. The model is developed and validated as a low carbon electricity planning tool to optimally meet the dynamic electricity demand and RPO targets as well as to manage the unmet total electricity demand and RPO targets. The Karnataka state electricity system (a state in south India) is chosen as a case study. The results suggest that Karnataka Electricity System is moving toward a sustainable renewable energy future even without any support from nonsolar Renewable Energy Certificate policy. However, policy interventions are critical for optimally utilizing the solar generation capacity.     

The plunge in German electricity futures prices – Analysis using a parsimonious fundamental model

The German market has seen a plunge in wholesale electricity prices from 2007 until 2014, with base futures prices dropping by more than 40%. This is frequently attributed to the unexpected high increase in renewable power generation. Using a parsimonious fundamental model, we determine the respective impact of supply and demand shocks on electricity futures prices. The used methodology is based on a piecewise linear approximation of the supply stack and time-varying price-inelastic demand. This parsimonious model is able to replicate electricity futures prices and discover non-linear dependencies in futures price formation. We show that emission prices have a higher impact on power prices than renewable penetration. Changes in renewables, demand and installed capacities turn out to be similarly important for explaining the decrease in operation margins of conventional power plants. We thus argue for the establishment of an independent authority to stabilize emission prices.     

The development of a green certificate market

Liberalizing the electricity industry and attempting to reduce the emissions of greenhouse gases are the two dominant trends in European energy policy. The last-mentioned issue might require the contribution from renewable energy technologies, but at present most renewables cannot compete on their own with conventional technologies. Thus, it can be expected that if renewables must compete solely on market conditions alone this will slow down or even halt the development of new renewable capacity. One model in which additional payments to renewable technologies are generated is based on the development of a separate green market. In Holland a voluntary green certificate market has existed since the beginning of 1998. In Denmark a comprehensive restructuring of the legislation for the electric power industry has just been completed, including the framework for developing a separate green market for renewable electricity production. The main objectives of introducing this type of electricity market in Denmark is to secure the development of renewable energy technologies (including contributions to greenhouse gas reductions), while at the same time releasing the Government from the (by now) quite heavy burden of subsidising renewable technologies. Finally, a green market will make it possible for these renewable technologies to be partly economically compensated for the environmental benefits, which they generate compared to conventional power production. With the recent Danish legislation as starting point this paper analyzes possible ways to set up a green certificate market, treating as well some of the consequences produced when the market is actually funtioning. The analysis is applicable for all renewable technologies, but special attention is given to wind power.     

Are government policies effective in promoting deployment of renewable electricity resources?

Using a panel data over 50 US states and years 1991–2007, this paper uses a state fixed-effects model with state-specific time-trends to estimate the effects of state policies on the penetration of various emerging renewable electricity sources, including wind, biomass, geothermal, and solar photovoltaic. Renewable portfolio standards with either capacity or sales requirements have a significant impact on the penetration of all types of renewables—however, this impact is variable depending on the type of renewable source: it is negative for combined renewables, wind, and biomass; and positive for geothermal and solar. Further, clean energy funds and required green power options mostly result in increasing the penetration of all types of renewables. On the other hand, voluntary renewable portfolio standards as well as state green power purchasing programs are found to be ineffective in increasing the penetration of any type of renewable source. Finally, economic variables, such as electricity price, natural gas price, and per capita GDP as well as structural variables, such as league of conservation voters rating and the share of coal-generated electricity are found to be generally insignificant, suggesting the crucial role of policy in increasing the penetration of renewables.