Energy strategies

The amount of fossil energy reserves and resources suggests a transition to our energy supply system that is based on a quasi-infinite fuel supply. Several options exist for this transition such as the nuclear breeder or solar power. Strategies for transitions have to meet a certain demand for energy. A simple but global scenario is given for such energy demand with emphasis on low demand in conjunction with fossil fuels. Consideration is given to the constraints of such fossil energy production and emphasis is put on the CO₂ problem. This allows a rough understanding of the time scale of such transitions. In view of the timing of the transition the various options for quasi-infinite supplies of energy are considered and priorities of a number of physics tasks are conceived.     

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.     

木薯乙醇-汽油混合燃料生命周期能源消耗多目标优化研究

建立了木薯乙醇—汽油混合燃料生命周期能源消耗单目标和多目标优化模型。以生命周期总体能源消耗、化石燃料消耗和石油消耗为优化目标，对木薯乙醇—汽油混合燃料生命周期能源消耗进行了单目标及多目标优化，并进行了灵敏度分析。结果表明：多目标优化能使木薯乙醇—汽油混合燃料的生命周期总体能源、化石燃料和石油消耗同时降低，可以为木薯乙醇—汽油混合燃料的应用提供决策依据，具有重要的应用价值。     

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.     

A review on process modeling and design of biohydrogen

The current energy supply depends on fossil fuels which have increased carbon dioxide emissions leading to global warming and depleted non-renewable fossil fuels resources. Hydrogen (H₂) fuel could be an eco-friendly alternative since H₂ consumption only produces water. However, the overall impacts of the H₂ economy depend on feedstock types, production technologies, and process routes. The existing process technologies for H₂ production used fossil fuels encounter the escalation of fossil fuel prices and long-term sustainability challenges. Therefore, biohydrogen production from renewable resources like biomass wastes and wastewaters has become the focal development of a sustainable global energy supply. Different from other biohydrogen production studies, this paper emphasizes biohydrogen fermentation processes using different renewable sources and microorganisms. Moreover, it gives an overview of the latest advancing research in different biohydrogen process designs, modeling, and optimization. It also presents the biohydrogen production routes and kinetic modeling for biohydrogenation.     

CO2 production rates for geothermal energy and fossil fuels

We calculate the CO₂ production rates for fossil fuels and three forms of geothermal energy. We show that most geothermal resources produce significantly less CO₂ than the fossil fuels for equivalent electricity production. We conclude geothermal energy may contribute to a reduction of global warming.     

A review: Energy recovery in batch processes

The implementation of batch processing has increased due to its intrinsic flexibility and adaptability. These are essential characteristics when it comes to producing high-value added materials such as agrochemicals, pharmaceuticals, specialty chemicals…the demand for which has grown in recent decades.Although industrial processes are highly diverse, a common feature to all is that they utilize fossil fuels as the energy source. The reliance on fossil fuels as a primary source of energy generates a negative impact on the environment. The implantation of renewable energies and efficient usage of energy has thus become crucial. Improving energy use could be achieved through advancements in plant machinery and the use of methodologies such as ‘process integration’.Process integration can be described as system oriented methods that could be used during the design and retrofit of industrial processes in order to obtain an optimal utilization of resources. The methods have traditionally focused on an efficient energy use, although recently process integration techniques cover other areas such as efficient use of raw materials, emission reduction and process operations. Energy integration tries to reach the optimization of heat, power, fuel and utilities.The consideration of energy integration complicates the process design and the generation of batch process design alternatives, so what is now required is the proposal and development of different approaches and methods oriented towards recovering energy in this kind of industrial process. Improving energy end-use efficiency will make it possible to reduce dependence on energy imports and bring about innovation and competitiveness.The aim of this work is report the main contributions that have been carried out in order to attain energy integration in batch processes, as well as different examples of applications that have shown the possibilities offered by the developed tools.     

Energy and environmental policies in China and Taiwan

Given the environmental problems, especially in developing countries, as well as new environmental laws limiting the use of fossil fuels, governments seek to replace fossil fuels with clean energies like renewable energies. The purpose of this study was to assess the development of renewable energy as well as reviewing the laws and policies of China and Taiwan in this regard. We also constructed different scenarios based on national sources, in consideration of a significant increase in the electrical power generation and a reduction in the CO₂ emission. Focus is placed on the renewable energy development and a significant reduction in the CO₂ emission. The results showed that the photovoltaic solar systems have the greatest benefits in energy production and CO₂ emission reduction in China and Taiwan. However, due to economic consideration and technical problems, there is still a long way to go.     

Artificial neural network analysis of world green energy use

This paper focuses on the analysis of world green energy consumption through artificial neural networks (ANN). In addition, the consumption is also analyzed of world primary energy including fossil fuels such as coal, oil and natural gas. A feed-forward back-propagation ANN is used for training and learning processes by taking into consideration data from the literature of world energy consumption from 1965 to 2004. Also, an ANN approach for forecasting world green energy consumption to the year 2050 is presented, and the consumption equations for different energy sources are derived. The environmental aspects of green energy and fossil fuels are discussed in detail. The resulting ANN-based equation curve profiles verify that the available economic reserves of fossil fuel resources are limited, and become “depleted” in the near future. It is expected that world green energy consumption will reach almost 62.74 EJ by 2010, and be on average 32.29% of total energy use between 2005 and 2025. However, world green energy and natural gas consumption will continue increasing after 2050, while world oil and coal consumption are expected to remain relatively stable after 2025 and 2045, respectively. The ANN approach appears to be a suitable method for forecasting energy consumption data, should be utilized in efforts to model world energy consumption.     

Energy access and security strategies in Small Island Developing States

Small Islands Developing States (SIDS) are isolated and surrounded by ocean. The generation and use of energy resources are two very important aspects for the development of SIDS. Unfortunately, most of SIDS do not use their potential in respect of energy resources, and they as a result have to depend on the import of fossil fuels in order to meet their energy needs. This increases the overall vulnerability of SIDS as they have to depend on the rising or fluctuating fossil fuels prices. Some SIDS, especially in the geographically dispersed Pacific region, do not have proper access to energy whereas other SIDS struggle more with energy security issue. At the same time, SIDS are most vulnerable to the impacts and effects of climate change, as they are among the ones to be most severely affected in case of natural calamities and sea-level rise.Drawing on experiences from Fiji and Mauritius, this paper explains core elements related to energy access and security in SIDS, contextualizes and discusses barriers and list some of the strategies that may be used to ensure access to and a continuous supply of energy in SIDS. A situational analysis of two SIDS outlines their current energy situation and compares their energy policies to globally accepted criteria for SIDS policies as well as with each other. It is claimed that the diverging energy performances of Fiji and Mauritius cannot be explained by policies differences. The reasons for the varying energy performances may therefore lie in the administrative and institutional mechanisms used by the two countries in implementing their energy policies. Finally, to enable SIDS to reduce their overall vulnerability and become truly sustainable islands, it is recommended to undertake careful assessments of the particular local contexts under which island energy regimes operate.     

Energy Evolution: Renewable energy in the Galápagos Islands

The inspiration of the theory of evolution, the Galápagos Islands, once again is exemplifying how species can evolve. The species presently evolving on the Galápagos Islands are not only the finches and giant tortoises, but the human species. The residents of this famous archipelago are in the process of converting the production of electrical energy and transportation from a 100% dependency on fossil fuels to a community based on 100% renewable and low/non-polluting resources. Seth Kassels, Renewable Energy Technician, Fundación Natura, Quito Ecuador reports.     

Renewable and sustainable energy use in Turkey: a review

Turkey is an energy importing nation with more than half of our energy requirements met by imported fuels. Air pollution is becoming a significant environmental concern in the country. In this regard, renewable energy resources are becoming attractive for sustainable energy development and environmental pollution mitigation in Turkey. Turkey's geographical location has several advantages for extensive use of most of these renewable energy sources. Because of this and our limited fossil fuel resources, a gradual shift from fossil fuels to renewables seems to be a serious alternative for Turkey's energy future. This article presents a review of the present energy situation and assesses sustainability, technical, and economical potential of renewable energy sources, and future policies for the energy sector in Turkey. Throughout the paper, problems relating to renewable energy sources, environment, and sustainable development are discussed for both current and future energy investments. The renewable energy potential of the country and its present status are evaluated.     

Political,economic and environmental impacts of biomass-based hydrogen

The purpose of this study is to assess the political, economic and environmental impacts of producing hydrogen from biomass. Hydrogen is a promising renewable fuel for transportation and domestic applications. Hydrogen is a secondary form of energy that has to be manufactured like electricity. The promise of hydrogen as an energy carrier that can provide pollution-free, carbon-free power and fuels for buildings, industry, and transport makes it a potentially critical player in our energy future. Currently, most hydrogen is derived from non-renewable resources by steam reforming in which fossil fuels, primarily natural gas, but could in principle be generated from renewable resources such as biomass by gasification. Hydrogen production from fossil fuels is not renewable and produces at least the same amount of CO₂ as the direct combustion of the fossil fuel. The production of hydrogen from biomass has several advantages compared to that of fossil fuels. The major problem in utilization of hydrogen gas as a fuel is its unavailability in nature and the need for inexpensive production methods. Hydrogen production using steam reforming methane is the most economical method among the current commercial processes. These processes use non-renewable energy sources to produce hydrogen and are not sustainable. It is believed that in the future biomass can become an important sustainable source of hydrogen. Several studies have shown that the cost of producing hydrogen from biomass is strongly dependent on the cost of the feedstock. Biomass, in particular, could be a low-cost option for some countries. Therefore, a cost-effective energy-production process could be achieved in which agricultural wastes and various other biomasses are recycled to produce hydrogen economically. Policy interest in moving towards a hydrogen-based economy is rising, largely because converting hydrogen into useable energy can be more efficient than fossil fuels and has the virtue of only producing water as the by-product of the process. Achieving large-scale changes to develop a sustained hydrogen economy requires a large amount of planning and cooperation at national and international alike levels.     

Energy availability problems with rapid deployment of wind-hydrogen systems

Given declining reliance on fossil fuels because of both their greenhouse gas emissions and depletion of reserves, renewable energy (RE) will need to become the main energy form. Most of the technical potential for RE is in intermittently available sources, mainly wind and solar. As penetration from these sources rises, conversion to another energy form, and energy storage, will be needed. Here we assume the energy carrier is hydrogen. This paper examines the consequences for net energy output over time for various rates of growth of wind-hydrogen systems. Wind energy is chosen for this case study because its output is presently far greater than solar, and because its costs are lower. We find that high growth rates of turbine-hydrogen installations lead to ‘boom and bust’ cycles in both equipment manufacture, and in net energy output. The main reason for these cycles is that such systems have high up-front input energy costs. To avoid these large swings, the rate of installation will have to be cut back, which limits the rate at which energy alternatives can supplant fossil fuels.     

Hydrogen as a renewable and sustainable solution in reducing global fossil fuel consumption

In this paper, hydrogen is considered as a renewable and sustainable solution for reducing global fossil fuel consumption and combating global warming and studied exergetically through a parametric performance analysis. The environmental impact results are then compared with the ones obtained for fossil fuels. In this regard, some exergetic expressions are derived depending primarily upon the exergetic utilization ratios of fossil fuels and hydrogen: the fossil fuel based global waste exergy factor, hydrogen based global exergetic efficiency, fossil fuel based global irreversibility coefficient and hydrogen based global exergetic indicator. These relations incorporate predicted exergetic utilization ratios for hydrogen energy from non-fossil fuel resources such as water, etc., and are used to investigate whether or not exergetic utilization of hydrogen can significantly reduce the fossil fuel based global irreversibility coefficient (ranging from 1 to +∞) indicating the fossil fuel consumption and contribute to increase the hydrogen based global exergetic indicator (ranging from 0 to 1) indicating the hydrogen utilization at a certain ratio of fossil fuel utilization. In order to verify all these exergetic expressions, the actual fossil fuel consumption and production data are taken from the literature. Due to the unavailability of appropriate hydrogen data for analysis, it is assumed that the utilization ratios of hydrogen are ranged between 0 and 1. For the verification of these parameters, the variations of fossil fuel based global irreversibility coefficient and hydrogen based global exergetic indicator as the functions of fossil fuel based global waste exergy factor, hydrogen based global exergetic efficiency and exergetic utilization of hydrogen from non-fossil fuels are analyzed and discussed in detail. Consequently, if exergetic utilization ratio of hydrogen from non-fossil fuel sources at a certain exergetic utilization ratio of fossil fuels increases, the fossil fuel based global irreversibility coefficient will decrease and the hydrogen based global exergetic indicator will increase.     

Energy caps: Alternative climate policy instruments for China?

Decoupling fossil energy demand from economic growth is crucial for China's sustainable development, especially for addressing severe local air pollution and global climate change. An absolute cap on coal or fossil fuel consumption has been proposed as a means to support the country's energy and climate policy objectives. We evaluate potential energy cap designs that differ in terms of target fuel, point of control, and national versus regional allowance trading using a global numerical general equilibrium model that separately represents 30 provinces in China. First, we simulate a coal cap and find that relative to a cap on all fossil fuels, it is significantly more costly and results in high localized welfare losses. Second, we compare fossil energy cap designs and find that a national cap on downstream fossil energy use with allowance trading across provinces is the most cost effective. Third, we find that a national fossil energy cap with trading is nearly as cost effective as a national CO₂ emissions trading system that penalizes energy use based on carbon content. As a fossil energy cap builds on existing institutions in China, it offers a viable intermediate step toward a full-fledged CO₂ emissions trading system.     

宁夏风力发电前景分析

能源是人类赖以生存的物质基础,是国民经济的基本支撑。中国的能源供应主要依靠煤炭、石油和天然气等化石能源,尤其是宁夏的能源供应主要依靠煤炭,但是化石能源资源的有限性及其开发利用过程对生态环境造成的巨大影响,严重制约经济社会的可持续发展。叙述了宁夏风能资源的现状,分析了风力发电的前景。     

Energy security vs. climate change: Theoretical framework development and experience in selected EU electricity markets

Electricity generation in different countries is based on a variety of fuel mixes compromising solid fossil fuels, oil, natural gas, nuclear and renewable energy sources. While in the past, national energy agendas have directed the optimal utilisation of domestic resources as a means to achieve supply security, today's environmental debates are influencing the electricity fuel mix in new directions. In this paper we examine the electricity sectors of Germany, Greece, Poland and the UK in an attempt to identify the policy and technology choices implemented in each country. The country selection is deliberately made to facilitate an extended overview of national agendas, varying domestic energy resources and industrialisation levels but still within the common EU framework. The focus is placed on policies related to two objectives, climate change mitigation and improving electricity supply security. The theoretical framework developed provides the possibility to assess the electricity sector independence at a national level using a multi-parametric analysis of the fuel mix data. Through a comparative assessment of the knowledge gained in different countries the authors provide insights and suggestions that allow for an improved understanding of the trade-offs and synergies that various policy options may introduce.     

可再生能源发展的必经过程和我国的政策取向

本文以学习曲线规律为理论依据,描述了可再生能源技术发展和产业成长的必经过程,以及可再生能源不同发展阶段所面临的障碍。分析了我国可再生能源的发展现状和所需要的支持政策的特点。同时分析了发展可再生能源与常规能源新技术之间的关系,探讨了常规能源的先进利用方式和可再生能源相互促进的发展思路。在此基础上提出我国应该按照发展阶段制订可再生能源的鼓励政策。     

Current scenario of biodiesel development in India: prospects and challenges

For a developing nation like India, the current energy portfolio is dominated by fossil fuels such as oil, coal, and petroleum products. Due to the rapid depletion and limited available resources, the price of fossil fuel increases. Also, fossil fuel induces climate change, environmental pollution, and rising global temperature. There is urgent need to shift from conventional energy to renewable energy source for sustainable and economic growth and to enhance a country’s energy security. Biofuel offers an attractive source of energy for the substitution of fossil fuels, and looking at the huge demand for diesel in all sectors of the economy, the biodiesel is being viewed as the best substitute for diesel. The other advantage for biofuel promotion in India is climate change mitigation through reduced greenhouse gas (GHG) emission. This article provides the current status of biodiesel development in India and discusses the role played by the centre and state government in promoting second-generation feedstock (nonedible seeds) and third-generation feedstock (algae) for biodiesel production.