Emerging technologies by hydrogen: A review

The majority of energy being used is obtained from fossil fuels, which are not renewable resources and require a longer time to recharge or return to its original capacity. Energy from fossil fuels is cheaper but it faces some challenges compared to renewable energy resources. Thus, one of the most potential candidates to fulfil the energy requirements are renewable resources and the most environmentally friendly fuel is Hydrogen. Hydrogen is a clean and efficient energy carrier and a hydrogen-based economy is now widely regarded as a potential solution for the future of energy security and sustainability. Hydrogen energy became the most significant energy as the current demand gradually starts to increase. It is an important key solution to tackle the global temperature rise. The key important factor of hydrogen production is the hydrogen economy. Hydrogen production technologies are commercially available, while some of these technologies are still under development. Therefore, the global interest in minimising the effects of greenhouse gases as well as other pollutant gases also increases. In order to investigate hydrogen implementation as a fuel or energy carrier, easily obtained broad-spectrum knowledge on a variety of processes is involved as well as their advantages, disadvantages, and potential adjustments in making a process that is fit for future development. Aside from directly using the hydrogen produced from these processes in fuel cells, streams rich with hydrogen can also be utilised in producing ethanol, methanol, gasoline as well as various chemicals of high value. This paper provided a brief summary on the current and developing technologies of hydrogen that are noteworthy.     

An energy picture of the Asian developing countries and research imperatives for energy development

The Asian developing countries are classified with respect to their socio-economic situation and energy resource endowment. Energy utilization levels for both commercial and biomass-based fuels are indicated in relation to resource availability. Renewable energy technologies and the potential in the region are briefly reviewed, as well as the technological potential and R&D activities for energy development. The paper concludes with a discussion of research imperatives for energy sector planning.     

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.     

可再生能源与能效项目中第三方融资的作用

新型可再生能源以及能效技术应用的主要的障碍之一，在于投资不足和对现代融资机制的操作和功能认识不足。传统融资方案的融资风险(也就是借贷方案、产权集资等)，加上先进可再生能源技术不断增加的技术及绩效方面的风险，对可再生能源项目的发展构成了额外的限制。现代融资机制提供一系列可供选择的优势，包括减少传统融资方案所承担风险的影响、为潜在投资者和能源用户提供具有吸引力的选项。可以预期，现代融资机制的应用将强化可再生能源技术的推广。文章全面介绍了第三方融资，以期能对可再生能源的发展和推广有所助益。     

Sustainable energy technologies in Israel under the CDM: Needs and prospects

The complexities related to the Clean Development Mechanism (CDM) are considered quite high and only a relatively low percentage of the existing potential has been exploited in the developing world. Israel obtains a significant unexploited potential, especially regarding Renewable Energy Sources (RESs) and Energy Efficiency (ENEF). In order to be able to identify potential CDM projects and to formulate a series of possible investment strategies with a CDM component, it is crucial to establish a clear understanding of the host country's needs and priorities, the suitable sustainable energy technologies, as well as their related potential benefits and barriers. The paper presents results obtained from an elaborated stakeholders' assessment on potential of sustainable energy technologies under the CDM conducted in Israel.     

Growth curves and sustained commissioning modelling of renewable energy: Investigating resource constraints for wind energy

Several recent studies have proposed fast transitions to energy systems based on renewable energy technology. Many of them dismiss potential physical constraints and issues with natural resource supply, and do not consider the growth rates of the individual technologies needed or how the energy systems are to be sustained over longer time frames. A case study is presented modelling potential growth rates of the wind energy required to reach installed capacities proposed in other studies, taking into account the expected service life of wind turbines. A sustained commissioning model is proposed as a theoretical foundation for analysing reasonable growth patterns for technologies that can be sustained in the future. The annual installation and related resource requirements to reach proposed wind capacity are quantified and it is concluded that these factors should be considered when assessing the feasibility, and even the sustainability, of fast energy transitions. Even a sustained commissioning scenario would require significant resource flows, for the transition as well as for sustaining the system, indefinitely. Recent studies that claim there are no potential natural resource barriers or other physical constraints to fast transitions to renewable energy appear inadequate in ruling out these concerns.     

Sustainable small-scale CHP technologies for buildings: the basis for multi-perspective decision-making

Generally speaking, the concept “small-scale CHP” (combined heat and power) means combined heat and power generation systems with electrical power less than 200 kW. The significant benefit of CHP is its overall efficiency, which can be as much as 85–90%. One of the most promising targets in the application of CHP lies in energy production for buildings. The most important competing technologies in this regard are reciprocating engines, micro-turbines, Stirling engines, and fuel cells. The benefit of these technologies is their ability to utilize sustainable fuels, like regenerative biomass, which makes them attractive. In spite of many technical and economic obstacles limiting the availability and feasibility of these technologies at the moment, the literature is optimistic about their future. The breakthrough of new technology is often regarded simply as a matter of decision-making.This article is a general review of issues that can be supposed to influence decisions when considering small-scale CHP as an alternative energy source for buildings. Firstly, a brief review is presented concerning the political, economic, social, and technological environment of small-scale energy production. Obstacles limiting the market potential of the new technologies are then listed, and solutions are suggested to improve their potential in Europe’s liberalizing energy market. The relevant interest groups influencing decisions both for and against the introduction of the new technologies, as well as their status are recognized. Finally, the advantages and disadvantages of relevant small-scale CHP technologies are briefly discussed, with respect to building energy generation. Finland’s role in this study is emphasized, but the international perspective is also dealt with.     

Analysis of renewable energy situation in Jordan

Jordan, like most developing countries, has problems, constraints, and difficulties that mandate increasing renewable energy (RE) technology utilization. The most effective argument, in favor of the adoption of RE technologies in Jordan, is that Jordan's lack of conventional energy sources is complemented by abundant RE resources. Because RE technologies are not complex, require less operating and maintenance costs, and are inherently more environmentally benign than conventional energy sources foster their consideration by energy policy makers as essential components of the national energy balance.The most prudent approach to address this strategic issue is to alleviate the problems, constraints, and difficulties associated with each of the above-mentioned influencing factors. This paper analyzes the current energy situation in Jordan and discuses the importance of increasing the role of RE technologies in the energy mix. It also discusses some success stories in the RE technologies domain, analyzes the barriers affecting their development, and suggests future courses of action in order to attain their maximum utilization potential. It is believed that this paper will benefit energy policy makers in Jordan, as well as in other developing countries.     

Energy savings potential of uninterruptible power supplies in European Union

Uninterruptible power supplies (UPS) are key components of information and communications technologies (ICT) systems, ensuring reliability by maintaining the continuity and quality of the systems’ power supply. The energy consumption of UPS should be an important consideration due to its high impact on the lifecycle costs, but in most applications of UPS, energy efficiency is not the most important issue, since the operational reliability of the ICT systems and the related security of data processing and storage are the major concerns. However, the conversion efficiency of UPS systems has been improving in recent years and high energy savings can be achieved with the adoption of new technologies without a reduction of the reliability levels. The Ecodesign Preparatory Study for UPS (Lot 27) aimed to identify and recommend ways to improve, at their design phase, the environmental performance of UPS in the European Union throughout their lifetime. This paper presents the work developed during the Preparatory Study for UPS focused on the technical analysis of the best available and not yet available technologies, as well as the potential energy savings that can be achieved. Several technologies were considered at component and product level. The main design options were then modelled, and the potential energy savings achievable with policy options focused on minimum efficiency performance standards and energy labelling were assessed, showing a potential for energy savings in European Union in 2025 of 11.4 TWh (65 % energy saving relative to predicted energy requirement of EU ICT system UPS based on current practice).     

Renewable energy market conditions and barriers in Turkey

Decentralized wind, hydropower, biogas and biomass, geothermal, solar thermal and solar electricity energy systems are the most commonly found renewable energy technologies promoted for rural energy supply within sustainable developments programs. They are, therefore, seen to have a central place in the practice of sustainable development and in allowing less development countries to bypass the environmentally damaging fossil fuel intensive paths made by industrialized countries. On the political front, many less development countries are critical of pressure on them to adopt environmental energy technologies.Turkey is situated the meeting point of three continents (Asia, Europe and Africa) and stands as a bridge between Asia and Europe. The country is located in southeastern Europe and southwestern Asia. As Turkey’s economy has expanded in recent years, the consumption of primary energy has increased. Presently in order to increase the energy production from domestic energy resources, decrease the use of fossil fuels as well as reduce of green house gas emissions different renewable energy sources are used for energy production in Turkey. The share of energy production from renewable energy sources has increased during the last 10 years. Turkey must import most of the energy to meet her needs. Turkey also has a large potential for renewable energies. The lack of knowledge about renewable energy technologies by most policy-makers, potential consumers, and energy firm managers has played against renewable energy developments. The paper presents renewable energy used in Turkey and Europe Union and evaluation of the market conditions and barriers of renewable energy use in Turkey.     

Renewable and sustainable approaches for desalination

Freshwater and energy are essential commodities for well being of mankind. Due to increasing population growth on the one hand, and rapid industrialization on the other, today's world is facing unprecedented challenge of meeting the current needs for these two commodities as well as ensuring the needs of future generations. One approach to this global crisis of water and energy supply is to utilize renewable energy sources to produce freshwater from impaired water sources by desalination. Sustainable practices and innovative desalination technologies for water reuse and energy recovery (staging, waste heat utilization, hybridization) have the potential to reduce the stress on the existing water and energy sources with a minimal impact to the environment. This paper discusses existing and emerging desalination technologies and possible combinations of renewable energy sources to drive them and associated desalination costs. It is suggested that a holistic approach of coupling renewable energy sources with technologies for recovery, reuse, and recycle of both energy and water can be a sustainable and environment friendly approach to meet the world's energy and water needs. High capital costs for renewable energy sources for small-scale applications suggest that a hybrid energy source comprising both grid-powered energy and renewable energy will reduce the desalination costs considering present economics of energy.     

Modeling technological learning and its application for clean coal technologies in Japan

Estimating technological progress of emerging technologies such as renewables and clean coal technologies becomes important for designing low carbon energy systems in future and drawing effective energy policies. Learning curve is an analytical approach for describing the decline rate of cost and production caused by technological progress as well as learning. In the study, a bottom-up energy-economic model including an endogenous technological learning function has been designed. The model deals with technological learning in energy conversion technologies and its spillover effect. It is applied as a feasibility study of clean coal technologies such as IGCC (Integrated Coal Gasification Combined Cycle) and IGFC (Integrated Coal Gasification Fuel Cell System) in Japan. As the results of analysis, it is found that technological progress by learning has a positive impact on the penetration of clean coal technologies in the electricity market, and the learning model has a potential for assessing upcoming technologies in future.     

Renewable energy resources and technologies applicable to Ireland

The energy consumed in Ireland is primarily achieved by the combustion of fossil fuels. Ireland's only indigenous fossil fuel is peat; all other fossil fuels are imported. As fossil fuels continually become more expensive, their use as an energy source also has a negative impact on the environment. Ireland's energy consumption can be separated into three divisions: transportation, electricity generation and heat energy. Ireland however has a vast range of high quality renewable energy resources. Ireland has set a target that 33% of its electricity will be generated from renewable sources by 2020 [I. Government. Delivering a Sustainable Energy Future for Ireland; 2007.]. The use of biomass, wind and ocean energy technologies is expected to play a major part in meeting this target. The use of renewable energy technologies will assist sustainable development as well as being a solution to several energy related environmental problems. This paper presents the current state of renewable energy technologies and potential resources available in Ireland. Considering Ireland's present energy state, a future energy mix is proposed.     

The development of bioenergy technology in China

Among renewable energy resources, bioenergy is one of the fastest growth energy alternatives with tremendous potential in China. The thermal, physical, and biological processes of conversion of biomass yield a number of products and can be obtained as gases, liquids, solid fuels, and electricity as well as a variety of chemicals. Various bioenergy technologies that have been developed are at the fundamental research, demonstration, and commercialization stages. This review concentrates on the processes that are attracting the most attention in China.     

The international energy agency cooperative programs on hydrogen: Past achievements and future potential

Work under the Hydrogen Agreement of the International Energy Agency was started in 1977. A cooperative research and development program has evolved around the production of hydrogen by thermochemical, electrolytic and photochemical methods. There has recently been added a new subject area relating to storage, energy conversion and safety.The first five years of the IEA program on hydrogen have seen considerable progress made towards the common goal of developing cost-effective, high-efficiency water-splitting technologies for use with renewable or inexhaustible energy sources. The past achievements and present programs are described. The current perception of the potential of hydrogen as an energy carrier is examined to permit a critical appraisal of the relevance of the content and scope of the cooperative program. Possible new research and development activities are discussed along with other factors which impact upon the adoption and/or viability of hydrogen energy technologies. The desirability of continuing and expanding international cooperative activities is considered as well as the directions of such activities and the obstacles to them.     

Potential for solar water heating in Zimbabwe

This paper discusses the economic, social and environmental benefits from using solar water heating (SWH) in Zimbabwe. By comparing different water heating technology usage in three sectors over a 25-year period, the potential of SWH is demonstrated in alleviating energy and economic problems that energy-importing countries like Zimbabwe are facing. SWH would reduce coincident electricity winter peak demand by 13% and reduce final energy demand by 27%, assuming a 50% penetration rate of SWH potential demand. Up to $250 million can be saved and CO₂ emissions can be reduced by 29% over the 25-year period. Benefits are also present at individual consumer level, for the electricity utility, as well as for society at large. In the case of Zimbabwe, policy strategies that can support renewable energy technologies are already in current government policy, but this political will need to be translated into enhanced practical activities. A multi-stakeholder approach appears to be the best approach to promoting widespread dissemination of SWH technologies.     

Energy vs food resource ratios for alternative energy technologies

Alternative energy technologies, particularly solar-based ones require large amounts of resources such as land and water that are also required for food production. Conflicts in resource use by energy and food production systems can be estimated quantitatively by a resource use ratio based upon the number of people that can be provided with either food or energy using the resources in question. Example analyses of selected alternative energy technologies demonstrate that alcohol from corn and eucalyptus farm technology have high potential, while wind and dry geothermal energy systems have low potential for conflict with food production. The approach presented provides a quantitative measure for assessing the issues arising when food resources are used for energy production.     

A review of energy storage technologies for wind power applications

Due to the stochastic nature of wind, electric power generated by wind turbines is highly erratic and may affect both the power quality and the planning of power systems. Energy Storage Systems (ESSs) may play an important role in wind power applications by controlling wind power plant output and providing ancillary services to the power system and therefore, enabling an increased penetration of wind power in the system. This article deals with the review of several energy storage technologies for wind power applications. The main objectives of the article are the introduction of the operating principles, as well as the presentation of the main characteristics of energy storage technologies suitable for stationary applications, and the definition and discussion of potential ESS applications in wind power, according to an extensive literature review.     

Bioenergy overview for Portugal

Bioenergy is seen as one of the key options to mitigate greenhouse gas emissions and substitute fossil fuels. Bioenergy is also an atypical energy source due to its diversity and inter-linkages with many other technological and policy areas. The goal of this paper is to analyze the Portuguese possibilities for bioenergy provision from biomass. The potentials of biomass, conversion technologies and legal framework are analysed and discussed. The result of this analysis shows that there are still unused potentials especially from forestry, which can contribute significantly to cover the bioenergy targets. However, the Portuguese experience with conversion technologies is limited to combustion, which is a drawback that must be solved so as to the bioenergy potential can be used. Research and Development projects, as well as demonstration projects are needed in order to improve the efficiency of the technological processes. At political level, Portuguese governments have been following the policies and strategies of the European Commission in the energy sector. However, energy crops market, due to the inter-linkage with agricultural policy, seems to need some additional political push.