Renewable energy in South Africa: Potentials,barriers and options for support

The challenge of transforming entire economies is enormous; even more so if a country is as fossil fuel based and emission intensive as South Africa. However, in an increasingly carbon constrained world and already now facing climate change impacts South Africa has to reduce greenhouse gas emissions intensity soon and decidedly. The South African electricity sector is a vital part of the economy and at the same time contributes most to the emissions problem. First steps have been taken by the South African government to enhance energy efficiency and promote renewable energy, however, they fail to show large-scale effects. This paper seeks to identify the relevant barriers to renewable energy investments and, based on experience from other countries, provide policy recommendations.     

Cobalt decorated graphitic carbon nitride photoanode for electrochemical ethanol oxidation: A sustainable way towards clean energy

Energy conversion devices based on liquid fuels have gained considerable attention in recent times to meet the increasing global demand for energy. In this work, graphitic carbon nitride (gCN) nanosheets have been synthesized by pyrolysis of urea and Co has been decorated in different molar ratios over its surface by the solution phase method. The prepared catalysts have been utilized for photo electrooxidation of ethanol, an anodic half-cell reaction in direct ethanol fuel cells. Electrochemical studies show that the catalyst containing 3 mol % of Co shows the best activity with a peak current density of 6.91 mA/cm² obtained at a peak potential of 0.28 V with maximum current density of 40 mA/cm². The effect of light on the catalytic activity has also been studied. On illuminating the surface of the electrode with light, an increment of 85% in current density is observed which indicates higher charge transfer that enhanced the photoactivity of the catalyst. This study confirms the practical applicability of the non-expensive carbonaceous material Co–C₃N₄ utilization as a photoanode in future energy systems.     

A new sustainable hydrogen clean energy paradigm

We analyze the feasibility of a novel, hydrogen fuel cell electric generator to provide power with zero noise and emissions for myriad ground based applications. The hydrogen fuel cell electric generator utilizes a novel, scalable apparatus that safely generates hydrogen (H₂) on demand according to a novel method, using a controlled chemical reaction between water (H₂O) and sodium (Na) metal that yields hydrogen gas of sufficient purity for direct use in fuel cells without risk of contaminating sensitive catalysts. The sodium hydroxide (NaOH) byproduct of the hydrogen producing reaction, is collected within the apparatus for later reprocessing by electrolysis, to recover the Na reactant. The detailed analysis shows that the novel, hydrogen fuel cell electric generator will be capable of meeting the clean power requirements for residential and commercial buildings including single family homes and light commercial establishments under a wide range of geographic and climatic conditions.     

Renewable energy conversion and utilization in ASEAN countries

The world population has passed six billion people and the pressure on basic daily needs is particularly dominant in the developing countries, such as the ASEAN. As most of the natural resources, particularly that of fossil fuel is depleting rapidly, more efficient ways to produce daily necessity are becoming important issues. In addition, both the UNFCCC and the Kyoto Protocol require, that efforts should be directed to improve efficiency of energy conversion devices, effective use of the clean and environmentally friendly renewable source of energy, beside providing sink for the green house gas (GHG) emissions. INFORSE report to the UN Secretary General indicated that the total energy sources in the industrialized countries will diminish drastically, but by providing enough funding for R/D in renewable energy conversion, about 50% of the world energy could be supplied by the developing countries by the year 2050.Despite the above limiting conditions, current data indicated growing energy demand in most of the developing countries, particularly in the ASEAN region. Consequently, these countries, should find out the best strategy in utilizing the available energy sources to maintain sustainable development. One of the reasonable option is to make use of the potential renewable energy resources within the countries and develop industries that complies with the unique characteristics of the energy, which is usually disperse, low density and mostly is still not yet competitive with power generation system using subsidized fuel price. Although some basic R/D on renewable energy technology is also being conducted in ASEAN, more effort, however, is directed to its immediate applications in providing basic energy need for rural house-hold, creating productive uses to process agricultural commodities, and to support general rural electrification programs. Such activity has been supported by relevant and operational government policies, international assistances, and gradual involvement of the private sectors.     

Coal and sustainable energy supply challenges and barriers

Coal is broadly recognized as secure, competitive, diversified, not vulnerable and predictable in price as an energy resource. In the power generation sector, coal is playing a dominant role in the EU-27 with 25% share of the total installed capacity and almost one-third of the power generation. The role played by the domestic resources and especially by coal is increasingly becoming the focus of the EU energy strategy.     

Renewable energy sources for clean and sustainable energy policies in Turkey

Energy is an essential factor to achieve sustainable development. So, countries striving to this end are seeking to reassess their energy systems with a view towards planning energy programmes and strategies in line with sustainable development goals and objectives. As would be expected, the rapid expansion of energy production and consumption has brought with it a wide range of environmental issues at the local, regional and global levels. States have played a leading role in protecting the environment by reducing emissions of greenhouse gases. Turkey is an energy importing country with more than half of the energy requirement being supplied by imports, and air pollution is becoming a great environmental concern in the country. On the other hand, Turkey's geographical location has several advantages for extensive use of most of the renewable energy sources. In this regard, renewable energy resources appear the most efficient and effective solutions for clean and sustainable energy development in Turkey. This paper provides an overview of global energy use and renewables for clean and sustainable energy policies in Turkey.     

Hydrogen from solar energy,a clean energy carrier from a sustainable source of energy

Solar energy is going to play a crucial role in the future energy scenario of the world that conducts interests to solar-to-hydrogen as a means of achieving a clean energy carrier. Hydrogen is a sustainable energy carrier, capable of substituting fossil fuels and decreasing carbon dioxide (CO₂) emission to save the world from global warming. Hydrogen production from ubiquitous sustainable solar energy and an abundantly available water is an environmentally friendly solution for globally increasing energy demands and ensures long-term energy security. Among various solar hydrogen production routes, this study concentrates on solar thermolysis, solar thermal hydrogen via electrolysis, thermochemical water splitting, fossil fuels decarbonization, and photovoltaic-based hydrogen production with special focus on the concentrated photovoltaic (CPV) system. Energy management and thermodynamic analysis of CPV-based hydrogen production as the near-term sustainable option are developed. The capability of three electrolysis systems including alkaline water electrolysis (AWE), polymer electrolyte membrane electrolysis, and solid oxide electrolysis for coupling to solar systems for H₂ production is discussed. Since the cost of solar hydrogen has a very large range because of the various employed technologies, the challenges, pros and cons of the different methods, and the commercialization processes are also noticed. Among three electrolysis technologies considered for postulated solar hydrogen economy, AWE is found the most mature to integrate with the CPV system. Although substantial progresses have been made in solar hydrogen production technologies, the review indicates that these systems require further maturation to emulate the produced grid-based hydrogen.     

The energy transition towards hydrogen utilization for green life and sustainable human development in Patagonia

Energy transitions towards cleaner and transparent systems in Patagonia are examined, considering energy data for hydrogen utilization to store variable renewable energy. The interrelated sectors – power, heating, cooling and transport – demand large amounts of energy and power. Wind transformation and distributed energy management can achieve synergies towards a new energy paradigm. Fossil fuels should be replaced by a system capable of storing massive amounts of electricity and fuels. Full energy services are not affordable employing only rechargeable batteries or air and water pumping. We analyze wind resources, electricity grids, and hydrogen developments carried out in Argentina, and the perspective of large wind-hydrogen facilities for export. We verify the current demand of natural gas and electricity, and propose the start of distributed production, management and utilization of hydrogen in Patagonia and to supply the most populated areas reaching Buenos Aires. Hydrogen sea transportation from South Patagonia to Rio de la Plata could be feasible. “The whole process would help the training of qualified human resources and also encourage the establishment of companies dedicated to renewable and hydrogen technology activities.”     

生物质洁净能源利用技术

生物质能是与环境友好的洁净能源，具有广阔的开发利用前景，综述了生物质能技术转换方式和可利用途径，介绍了国内外利用生物质能的状况。     

Hydropower in Turkey for a clean and sustainable energy future

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. This paper deals with policies to meet increasing energy and electricity demand for sustainable energy development in Turkey. 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's total economically usable small hydropower potential is 3.75 GWh/year.     

Spanish energy planning towards a sustainable future

There is a growing awareness among all countries and their decision makers, regardless of economic and industrial development, that the environment must be protected, leading towards a sustainable future. This is especially important in the energy sector—which is the principal factor in economic and industrial development—since the primary energy sources of today, fossil fuels, are the main culprits of global environmental problems, such as the greenhouse effect, ozone layer depletion, acid rains and pollution. Industrial countries, being greater consumers of fossil fuels, are affected to a greater extent by their environmental harms. Consequently, these countries are leading the way in environmental protection measures.The European Union, the second largest industrial grouping in the world, has become one of the leaders in taking important measures in the energy sector to curb the harmful emissions over the years. Spain, a member of the European Union, has initiated planning to reduce the pollutants produced by the energy sources and bring them in line with the European Union efforts, while keeping up the country's economic development. This paper reports the efforts and planning of Spain through the year 2010 to comply with the European Union environmental regulations on one hand and to sustain economic development on the other.     

Local communities towards a sustainable energy future: needs and priorities

The local authorities demonstrate their willingness to implement sound local sustainable energy policies, especially through their participation in the Covenant of Mayors (CoM). However, in rural environments, namely areas outside of large cities and towns, fulfilling their CoM commitments, especially as regards the local energy planning at the medium- to long-term scale, can come with very different and sometimes challenging constraints. In this context, the main objective of this paper is the assessment of the local communities’ needs and priorities, so as to identify the key parameters that should be taken into consideration during the development of their Sustainable Energy Action Plan. The adopted approach was implemented in rural communities from four countries (Austria, Croatia, Greece and Portugal). From the results obtained, the need for a methodology, appropriately customised to the rural communities’ characteristics, was determined, addressing especially interested stakeholders who are not ‘experts’ in the field.     

Potential of sustainable energy technologies under CDM in Thailand: Opportunities and barriers

The paper presents results obtained from a much elaborated stakeholders’ assessment on potential of sustainable energy technologies conducted in Thailand. It also gives an overview of the status of clean development mechanism (CDM) portfolio in Thailand. The stakeholders from different sectors were contacted during the research and their feedbacks on potential of different technologies under CDM were discussed through a series of bilateral interviews. With the few selected technologies suitable in the context of CDM opportunities in Thailand, the sustainability benefits and barriers to their implementation are also discussed in detail. The suggestions provided by the stakeholders in overcoming a few key barriers are also given in the paper.     

Energy conservation policy and environment for a clean and sustainable energy future

One of the most serious difficulties facing humanity is the need for a sustainable future. Maintaining nonrenewable energy resources for future generations is a main purpose of sustainability. However, for sustainable future, produced and consumed energy should support human development all social, economic and environmental dimensions. Problems related with environment and energy shortages have put all circles to the task of actively promoting education in energy conservation. Therefore, many countries have started to identify their responsibility for decreasing the unfavorable effect of high energy use on the environment. The primary contribution of this paper will be to ensure energy conservation policy advices to decrease climate change without effecting economic growth for a clean and sustainable energy future.     

An innovation idea for energy transition towards sustainable and resilient societies: Global energy interconnection

Global Energy Interconnection(hereafter GEI) is not only connectivity of power grid, but also a series of methodical innovations for energy transition towards sustainable and resilient societies,which is different from the traditional energy development mode in the past. This paper seeks to summarize the key features about the above-mentioned innovations, as Green & Clean, Balanced & Reciprocal, Efficient & Intelligent and Vitality & Business opportunity. Finally it puts forward some reflections on the future development of GEI based on ASEAN practice cases.     

Leading global energy and environmental transformation: Unified ASEAN biomass-based bio-energy system incorporating the clean development mechanism

In recent years, the ten member countries in the Association of Southeast Asia Nations (ASEAN) have experienced high economic growth and, in tandem, a substantial increment in energy usage and demand. Consequently, they are now under intense pressure to secure reliable energy supplies to keep up with their growth rate. Fossil fuels remain the primary source of energy for the ASEAN countries, due to economic and physical considerations. This situation has led to unrestrained emissions of greenhouse gases to the environment and thus effectively contributes to global climate change. The abundant supply of biomass from their tropical environmental conditions offers great potential for ASEAN countries to achieve self-reliance in energy supplies. This fact can simultaneously transform into the main driving force behind combating global climate change, which is associated with the usage of fossil fuels. This research article explores the potential and advantages for ASEAN investment in biomass-based bio-energy supply, processing and distribution network with an emphasis on regional collaborations. It also investigates the implementation and operational challenges in terms of political, economic and technical factors for the cross-border energy scheme. Reliance of ASEAN countries on the clean development mechanism (CDM) to address most of the impediments in developing the project is also under scrutiny. Unified co-operation among ASEAN countries in integrating biomass-based bio-energy systems and utilising the clean development mechanism (CDM) as the common effort could serve as the prime example for regional partnerships in achieving sustainable development for the energy and environmental sector in the future.     

能源利用可持续发展的热力学分析

自可持续发展的概念提出后，人们以各种理论或模型去描述能源的有效利用，多数给出趋于乐观的前景。从热力学熵增原理，分析耗散结构三个重要环节的可持续性，即导入的可持续性源于各种资源供应的可满足性；代谢的可持续性应具有科学的预见性和自觉的协调性；废弃的可持续性应立足于废弃物的可再生性和可处置性。得出可持续发展的关键在于能源供应的可持续性以及人类社会生产和生活方式与自然界自觉有效的协调。提出能源有效利用、节能和新能源开发研究是当前与今后的重要任务，并加强用能可持续发展的世界观教育公民。     

Load management for refrigeration systems: Potentials and barriers

As a strategy to deal with the increasing intermittent input of renewable energy sources in Germany, the adaptation of power consumption is complementary to power-plant regulation, grid expansion and physical energy storage. One demand sector that promises strong returns for load management efforts is cooling and refrigeration. In these processes, thermal inertia provides a temporal buffer for shifting and adjusting the power consumption of cooling systems. We have conducted an empirical investigation to obtain a detailed and time-resolved bottom-up analysis of load management for refrigeration systems in the city of Mannheim, Germany. We have extrapolated our results to general conditions in Germany. Several barriers inhibit the rapid adoption of load management strategies for cooling systems, including informational barriers, strict compliance with legal cooling requirements, liability issues, lack of technical experience, an inadequate rate of return and organizational barriers. Small commercial applications of refrigeration in the food-retailing and cold storage in hotels and restaurants are particularly promising starting points for intelligent load management. When our results are applied to Germany, suitable sectors for load management have theoretical and achievable potential values of 4.2 and 2.8 GW, respectively, amounting to about 4–6% of the maximum power demand in Germany.     

加强洁净能源开发利用几个问题的探讨

本文简述推广使用洁净能源的重要意义 ,从体制改革、政府职能、市场建设、经济与技术政策、科技进步和公众参与等方面探讨加快洁净能源发展的问题。