Overview of renewable energy sources in the Republic of the Sudan

Sudan is an agricultural country with fertile land, plenty of water resources, livestock, forestry resources and agricultural residues. An overview of the energy situation in Sudan is introduced with reference to the end uses and regional distribution. Energy sources are divided into two main types: conventional energy (biomass, petroleum products and electricity) and non-conventional energy (solar, wind, hydro, etc.). Sudan possesses a relatively high abundance of solar radiation, moderate wind speeds, hydro and biomass energy resources. Application of new and renewable sources of energy available in Sudan is now a major issue in strategic planning for alternatives to fossil fuels to provide part of local energy demand. Sudan is an important case study in the context of renewable energy. It has a long history of meeting its energy needs through renewables. Sudan’s renewables portfolio is broad and diverse, due in part to the country’s wide range of climates and landscapes. Like many of the African leaders in renewable energy utilisation, Sudan has a well-defined commitment to continue research, development and implementation of new technologies. Sustainable low-carbon energy scenarios for the new century emphasise the untapped potential of renewable resources. Rural areas of Sudan can benefit from this transition. The increased availability of reliable and efficient energy services stimulates new development alternatives. Renewable environmentally friendly energy must be encouraged, promoted, implemented and demonstrated, for use in the Republic of the Sudan.     

Electricity sector in Mexico: Current status. Contribution of renewable energy sources

The challenge facing the world electricity sector is the cost incurred in maintaining the system and seeing to the environmental effects it causes. In Mexico the grid is supplied by thermal plants fed by oil products. Its great potential of renewable energies clearly shown in studies by national and international scholars has led the government to become more committed to take advantage of these energies. The goal is to reduce dependence on fossil fuels to generate electricity and to reduce the emission of greenhouse gases. In this article we analyse the current state of renewable energies, the conditions needed to foster them and the legislative changes already introduced to promote their greater part in the national electricity grid.     

Feasibility study of renewable energy sources for developing the hydrogen economy in Pakistan

Hydrogen energy can play a pivotal part in enhancing energy security and decreasing hazardous emissions in Pakistan. However, hydrogen energy can be sustainable and clean only if it is produced from renewable energy sources (RES). Therefore, this study conducts feasibility of six RES for the generation of hydrogen in Pakistan. RES evaluated in this study include wind, solar, biomass, municipal solid waste (MSW), geothermal, and micro-hydro. RES have been evaluated using Fuzzy Delphi, fuzzy analytical hierarchy process (FAHP), and environmental data envelopment analysis (DEA). Fuzzy Delphi finalizes criteria and sub-criteria. FAHP obtains relative weights of criteria considered for choosing the optimal RES. Environmental DEA measures relative efficiency of each RES using criteria weights as outputs, and RES-based electricity generation cost as input. The results revealed wind as the most efficient source of hydrogen production in Pakistan. Micro-hydro and Solar energy can also be used for hydrogen production. Biomass, MSW, and geothermal achieved less efficiency scores and therefore are not suggested at present.     

Mapping the potential for decentralized energy generation based on renewable energy sources in the Republic of Croatia

There are regions in the Republic of Croatia (underdeveloped, devastated by war, depopulated, as well as islands and mountainous areas) which are still disconnected from the electricity network or where the current network capacity is insufficient. In addition, these regions have good renewable energy potential. Since the decentralized energy generation (DEG) covers a broad range of technologies, including many renewable energy technologies (RET) that provide small-scale power at sites close to the users, this concept could be of interest for these locations. This paper identifies the areas in Croatia where such systems could be applied. Consideration is given to geographical locations as well as possible applications. Wind, hydro, solar photovoltaic, geothermal, and biomass conversion systems were analyzed from a technological and economic point of view. Since the renewable energy sources (RES) data for Croatia are rather scarce, the intention was to give a survey of the present situation and an estimate of future potential for DEG based on RES. The energy potential (given as capacity and energy capability) and production costs were calculated on a regional basis and per type of RET. Finally, the RES cost–supply curves for 2006 and 2010 are given.     

Life-cycle assessment in the renewable energy sector

The Polish energy industry is facing challenges regarding energetic safety, competitiveness, improvement of domestic companies and environmental protection. Ecological guidelines concern the elimination of detrimental solutions, and effective energy management, which will form the basis for sustainable development. The Polish power industry is required to systematically increase the share of energy taken from renewable sources in the total energy sold to customers. Besides the economic issues, particular importance is assigned to environmental factors associated with the choice of energy source. That is where life-cycle assessment (LCA) is important. The main purpose of LCA is to identify the environmental impacts of goods and services during the whole life cycle of the product or service. Therefore LCA can be applied to assess the impact on the environment of electricity generation and will allow producers to make better decisions pertaining to environmental protection. The renewable energy sources analysed in this paper include the energy from photovoltaics, wind turbines and hydroelectric power. The goal and scope of the analysis comprise the assessment of environmental impacts of production of 1 GJ of energy from the sources mentioned above. The study will cover the construction, operation and waste disposal at each power plant. Analysis will cover the impact categories, where the environmental influence is the most significant, i.e. resource depletion, global warmth potential, acidification and eutrophication. The LCA results will be shown on the basis of European and Australian research. This analysis will be extended with a comparison between environmental impacts of energy from renewable and conventional sources. This report will conclude with an analysis of possibilities of application of the existing research results and LCA rules in the Polish energy industry with a focus on Poland's future accession to the European Union. Definitions of LCA fundamental concepts, its methodology and application are described in the ISO 14040-14049 series of standards. These standards have already been introduced in some countries, but in Poland they are still at the stage of translation into Polish. Nevertheless some companies in Poland try to assess how their products influence the environment and what are the possibilities of technology improvement in the existing production process reduce their environmental impact.     

国内可再生能源新闻

太阳能中国环境标志太阳能标准颁布,首批21家企业获得认证(本刊记者王廷飞)继不久前有关领导透露太阳能热水器行业国家标准将有所提高之后,国家环保总局也出新举措,于日前颁布了专门针对太阳能     

可再生能源发电

可再生能源是指不会随人类的开发利用而衰减的能源,如风能、太阳能、生物质能、小水电（指设计能力低于２５兆瓦的工程）、海洋能、垃圾再利用能源、垃圾掩埋沼气、污水处理沼气、地热能等。我国的自然资源总量排世界第７位,能源资源总量居世界第３位。其中可再生能源资源尤其丰富,可开发风能资源２．５亿千瓦,水能资源７５４０万千瓦,生物质能１．２５亿千瓦,地热能６７０万千瓦,另外还有数量巨大的太阳能及城市垃圾利用潜力。１我国太阳能资源我国地处北半球欧亚大陆的东部,幅员辽阔,有着十分丰富的太阳能资源。我国各地的太阳辐…     

西藏可再生能源详考

西藏自治区是我国的西南屏障，具有十分重要的战略地位。最近几年，随着改革开放的进一步深入和西部大开发的全面实施，西藏正在逐步加大对外开放的力度，以吸引更多的投资和建设项目。但是，由于西藏的地理条件和自然条件的限制，交通和电力等基础设施的相对落后，已经成为制约西藏发展的瓶颈。我国政府投入了大量的财力和物力发展可再生能源，现正在西部部分省份实施利用可再生能源发电解决无电乡镇的用电问题，即“光明工程”。其中西藏自治区是“光明工程”的重中之重。为了更为有效地在西藏自治区发展和利用太阳能，解决电网无法覆盖地…     

Exergy analysis of renewable energy sources

Oil crises in the past years made more obvious the dependency of economies on fossil fuels. As a consequence, the need for new energy sources became more urgent. Renewable energy sources could provide a solution to the problem, as they are inexhaustible and have less adverse impacts on the environment than fossil fuels. Yet, renewable energy sources technology has not reached a high standard at which it can be considered competitive to fossil fuels. The present study deals with the exergy analysis of solar energy, wind power and geothermal energy. That is, the actual use of energy from the existing available energy is discussed. In addition, renewable energy sources are compared with the non-renewable energy sources on the basis of efficiency.     

Private sector investment in renewable energy utilisation: strategic analysis of stakeholder perspectives in developing countries

Private sector encouragement in the development programmes of renewable energy (RE) utilisation is one of the important subjects and challenges for governments of developing countries. While profit in short-term and market-based orientation are the dominant approach of private sector to start an investment, governments and policymakers are paying special attention to participation of private investments to achieve their long-term development plans. In contrast, academic researchers notice to private investments in a structure that is sometimes in conflict with private investors and policymakers perspectives. Therefore, each group of stakeholders has its own priorities that negatively affect promotion and adoption plans of renewable alternatives utilisation. This article reviews and analyses different perspectives of RE stakeholders (beneficiaries) to encourage participation of private investments Differences in priorities, concerns, and interests in each group of stakeholders are the subjects that are discussed in the article. To close the attitudes and perspectives, a recommendations package is also presented in two levels of operational and strategic     

On the economics of hydrogen from renewable energy sources as an alternative fuel in transport sector in Austria

The core objective of this work is to analyse the possible future relevance of hydrogen from renewable energy sources in the transport sector from an economic point-of-view with special focus on Austria. The analysis is conducted in a dynamic framework until 2050.     

The analysis of the renewable energy production sector in Serbia

Producing energy from renewable sources in Serbia is in its initial phase, and therefore this paper points towards the basic assumptions, potentials and institutional framework for the development of this activity in Serbia. Until recently, production and consumption of energy in Serbia was a social category, but the shift towards market economy together with the fact that Serbia has adopted Kyoto protocol, production of energy from renewable sources became a competitive and obligatory activity. Research shows that the current potentials for producing energy from renewable sources in Serbia are favorable. Besides this, the paper provides an overview of the existing institutional structure in the energy sector in Serbia, but also the short overview of the adequate legal acts. Researches that were done so far have proven that energy potentials of Serbia are insufficiently known and therefore authors will give an overview of the foreign investments in this sector and reveal the possibilities for further investing. Considering the existing know-how base and potentials for the production of equipment, geothermal energy and energy coming from biomass have been identified as priority renewable sources of energy. Producing energy from other renewable sources is also possible, but would require substantial foreign investments. As a final conclusion, the paper states that completely unused potentials for production of energy from renewable sources, together with adequately set institutional framework, would create great possibilities for foreign investments.     

Cyprus energy system and the use of renewable energy sources

Cyprus is an island state whose energy production is almost completely dependent on imported hydrocarbon fuels. Its electricity production sector is more than 90% dependent on oil products while the remaining 9% are covered by imports of coal (4.5%) and by solar energy (4.5%). Because Cyprus will become a full member of the European Union (EU), it becomes essential to follow the EU white paper rules and insert renewable energy sources (RES) as part of its energy production system. Solar, wind energy and biomass are the three available forms of RES. This paper will examine and analyze the energy system of Cyprus. It will examine the RES available and the extent of the energy needs could be satisfied by them.     

Assessing the potential of renewable energy sources in Turkey

To meet Turkey’s growing energy demand, the installed electric power capacity of 27.8 GW in 2001 has to be doubled by 2010 and increased fourfold by 2020. The difference between Turkey’s total primary energy supply (TPES) of from its own sources and total final consumption (TFC) is projected grow from 1 quad (1.06–2.06) in 1999 to 5.71 quads (2.79–8.5) in 2020 (1 QUAD=293.071 TWh). Turkey’s limited amount of fossil fuels has a present average ratio of proved reserves of 97.38 quads to production rate of 3.2 quads yr⁻¹ of about 30 years. Turkey’s reliance on fossil fuel-based energy systems to meet the growing demand is most likely to exacerbate the issues of energy insecurity, national environmental degradation, and global climate change in increasing proportions. Economically-feasible renewable energy potential in Turkey is estimated at a total of ca. 1.69 quads yr⁻¹ (495.4 TWh yr⁻¹) with the potential for 0.67 quads yr⁻¹ (196.7 TWh yr⁻¹) of biomass energy, 0.42 quads yr⁻¹ (124 TWh yr⁻¹) of hydropower, 0.35 quads yr⁻¹ (102.3 TWh yr⁻¹) of solar energy, 0.17 quads yr⁻¹ (50 TWh yr⁻¹) of wind energy, and 0.08 quads yr⁻¹ (22.4 TWh yr⁻¹) of geothermal energy. Pursuit and implementation of sustainability-based energy policy could provide about 90 and 35% of Turkey’s total energy supply and consumption projected in 2010, respectively. Utilization of renewable energy technologies for electricity generation would necessitate about 23.2 Mha (29.8%) of Turkey’s land resources.     

Identifying barriers in the diffusion of renewable energy sources

Rapid diffusion of renewable energy sources (RES) in the electricity power sector is crucial if the EU wants to fulfill its 2050 CO₂ reduction commitments. For this reason, identifying and alleviating all barriers that hinder the development of RES is necessary to the successful deployment of these technologies. This paper discusses the main barriers in the diffusion of wind and photovoltaic (PV) solar power in the Greek electricity sector by drawing on the literature of technological innovation systems and system functions. Furthermore, we provide an explanation of the different diffusion rates between the two technologies. Inadequate financial resources, low grid capacity, delays in the issuance of building permits, opposition from local communities to the construction of wind farms and the lack of a stable institutional framework are among the most important barriers that inhibit the diffusion of the wind and PV solar power. The nature of the barriers identified in this study calls for policy intervention.     

Seawater desalination using renewable energy sources

The origin and continuation of mankind is based on water. Water is one of the most abundant resources on earth, covering three-fourths of the planet's surface. However, about 97% of the earth's water is salt water in the oceans, and a tiny 3% is fresh water. This small percentage of the earth's water—which supplies most of human and animal needs—exists in ground water, lakes and rivers. The only nearly inexhaustible sources of water are the oceans, which, however, are of high salinity. It would be feasible to address the water-shortage problem with seawater desalination; however, the separation of salts from seawater requires large amounts of energy which, when produced from fossil fuels, can cause harm to the environment. Therefore, there is a need to employ environmentally-friendly energy sources in order to desalinate seawater.After a historical introduction into desalination, this paper covers a large variety of systems used to convert seawater into fresh water suitable for human use. It also covers a variety of systems, which can be used to harness renewable energy sources; these include solar collectors, photovoltaics, solar ponds and geothermal energy. Both direct and indirect collection systems are included. The representative example of direct collection systems is the solar still. Indirect collection systems employ two sub-systems; one for the collection of renewable energy and one for desalination. For this purpose, standard renewable energy and desalination systems are most often employed. Only industrially-tested desalination systems are included in this paper and they comprise the phase change processes, which include the multistage flash, multiple effect boiling and vapour compression and membrane processes, which include reverse osmosis and electrodialysis. The paper also includes a review of various systems that use renewable energy sources for desalination. Finally, some general guidelines are given for selection of desalination and renewable energy systems and the parameters that need to be considered.     

Optimal model of congestion management in deregulated environment of power sector with promotion of renewable energy sources

In the competitive electricity market it becomes very much important to give special consideration for development of renewable energy sources (RESs) due to environmental and other social problems related with conventional generations. So this paper presents an optimal model of congestion management with special emphasis for promotion of RES in competitive electricity market. This paper presents a generalized optimal model of congestion management for deregulated power sector that dispatches the pool in combination with privately negotiated bilateral and multilateral contracts while maximizing social benefit. This model determines the locational marginal pricing (LMP) based on marginal cost theory. It also determines the size of non-firm transactions as well as pool demand and generations. Both firms as well as non-firm transactions are considered in this model. The proposed model has been applied to IEEE-30 bus test system with addition of some RES for analysis of the proposed model. The RES supplies its power to load either through the firm transaction or through power pool. The power from RES is not subjected to any curtailment in proposed model of congestion management.