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In view of the climate crisis, the development and the path of growth and expansion of renewable energy systems is an urgent task, but must carried out with great care on environmental compatibility and protection. Renewable energy supply systems that are suitable for grid-bound heat supply, particularly in urban areas in Europe, are geothermal binary plants that provide power as well as power and heat. This paper will present studies whose objective was the assessment of hydrogeothermal power and heat generation in low-enthalpy regions from the environmental standpoint. The German Environment Agency published results of a network of studies conducted between 2008 and 2016 on the analysis of detailed and comprehensive environmental impacts of the geothermal energy generation in Germany and has continuously evaluated these findings. In this article, the results of the Life Cycle Assessment are discussed, taking into account all effects and material flows within the entire life cycle. Based on these balances, differing geothermal systems are compared to each other and to other renewable and fossil energy generation systems in order to assess the ecological advantages and disadvantages of these systems. Taking into account local environmental impacts as well a comprehensive ecologic evaluation of potential environmental and human health impacts becomes possible. The paper presents the results of a) the mass and energy fluxes of the process chain along the life cycle, and b) the local environmental impacts along the life cycle with regard to the environmental indicators of these cases. The focus is on the impact of site and plant parameters. Concluding, it can be summarised that geothermal power and heat generation is a very low-carbon technology and can contribute to a sustainable energy supply. Hydrogeothermal plants show a significantly low surface consumption, and environmental impacts are only locally relevant and technically controllable. Through the development of optimised overall concepts, geothermal based power and heat generation can achieve minimal environmental impacts in all areas. The combined heat and power generation from geothermal resources is by far the most environmentally and climate-friendly energy supply compared to all other regenerative and fossil systems. [ABSTRACT FROM AUTHOR]

This paper aims to identify institutional improvement measures to promote environmentally sustainable ocean renewable energy development by analyzing how the environmental assessment systems in South Korea are integrated into this development. The measures identified in the paper include (1) consideration of subjecting ocean renewable energy development to strategic environment assessment in order to assess the adequacy of relevant project plans and the validity of site selection at early stages, (2) new standards, such as the area of occupancy, integrated within the environmental impact assessment at the project implementation stage, (3) integration of the environmental impact assessment with the procedures for Consultation on Utilization of Sea Areas to reduce development cost and delays and (4) reinforcement of post-development environmental monitoring processes to eliminate uncertainty or lack of knowledge about potential impacts on marine environment and habitat caused by development. [ABSTRACT FROM AUTHOR]

Typically environmental Kuznets curve (EKC) studies on energy concentrate on the emissions produced from energy production or consumption and neglect the aspect of exhaustion of a natural resource, which is an irreversible result, against any definition of sustainability and intergenerational equity. This paper investigates whether there is an environmental Kuznets curve for renewable energy, whether there should be one and if there is, what it should stand for. For this reason the paper employs balanced panel data for 33 European member and candidate state countries that produce crude oil, natural gas, coal and renewable energy for the years 1990–2010 to investigate the relationship between their scale of economic activity, fossil energy production and the production of renewable energy. Results from random effects models together with Arellano Bond estimator models identify the U-shape for the environmental Kuznets curve only for renewable energy and coal production. A theoretical justification on the mechanisms possibly driving the environmental Kuznets curve for renewable energy are also discussed. [ABSTRACT FROM AUTHOR]

Rapidly increasing energy demand and growing concern about economic and environmental consequences call for renewable/sustainable energy technologies׳ adoption in India. Renewable/sustainable energy technologies have faced a number of constraints that have affected their rate of adoption. In this paper an attempt has been made to identify and rank the major barriers in the adoption of ‘renewable and green’ energy technologies in the Indian context. Twenty-eight barriers have been identified from an extensive literature review. These identified barriers have been categorized into seven dimensions of barriers, i.e. Economical & Financial; Market; Awareness & Information; Technical; Ecological and Geographical; Cultural & Behavioral; and Political & Government Issues. Analytical Hierarchy Process (AHP) technique has been utilized for ranking of barriers to adopt renewable/sustainable technologies in the Indian context. All pair comparisons in AHP have been made based on experts’ opinions (selected from academia and industry). Sensitivity analysis has also been made to investigate the priority ranking stability of barriers to adopt renewable/sustainable technologies in the Indian context. This paper may help practitioners, regulators and academician focus their future efforts in adoption of ‘renewable/sustainable energy technologies’ in India. Further, this understanding may be helpful in framing the policies and strategies towards adoption of renewable/sustainable energy technologies. [ABSTRACT FROM AUTHOR]

Facing the mounting pressures of meeting energy and environment needs and reducing its dependence for fossil fuels, China needs to make more effort to develop renewable energy. This paper attempts to use portfolio theory to optimize China's overall energy system with considering the learning curve effect of renewable energy cost and the characteristic of fossil energy cost increasing over time. It also takes into account additional factors such as environmental costs of coal consumption and various growth rates of the cumulative R&D (research and development) capacity for solar power. This research has found that the development of renewable energy in China has tremendous potential but it will not replace fossil energy in the next decades. The sensitivity analysis of this paper indicates that development of solar power is driven not only by the cumulative installed capacity but also by the cumulative R&D capacity. [ABSTRACT FROM AUTHOR]

Evaluating the environmental sustainability performance of a nation is complex. This paper considers the merits of environmental indices, and how effective they are when assessing the environmental sustainability of any nation. The simplicity and generic qualities of environmental indices currently necessitates a much broader analysis in order to evaluate any nation׳s genuine environmental sustainability credentials – ultimately the development of a synthetic Environmental Sustainability Index is required to fulfil this task. Using Iceland as a case study, this paper reviews the usefulness of four selected environmental indices (Environmental Vulnerability Index, Environmental Performance Index, Ecological Footprint and Happy Planet Index) for governance institutions when formulating reasoned responses to challenges. By adopting a holistic methodology, Iceland׳s environmental sustainability credentials are critically examined in this paper, with particular focus given to the impacts deriving from expanded renewable energy utilisation in recent years. Abundant geothermal and hydropower energy resources have been increasingly used to power heavy industry, particularly aluminium production. The wider health implications and long-term environmental sustainability consequences of renewable energy utilisation have not been analysed in depth within any of the indices. Socio-economic progress in Iceland has also been attained alongside the imposition of the highest ecological footprint of any nation in the world. As such, economic activities in Iceland have not occurred in accordance with commonly accepted notions of sustainable development, which is focused upon the reconciliation of economic, environmental and social objectives, together with recognition of current and future need across these domains. [ABSTRACT FROM AUTHOR]

A growing literature suggests that community owned renewable energy (CRE) projects have the potential to deliver a range of environmental and local socio-economic benefits. There is relatively little empirical evidence to substantiate this, with few systematic efforts to assess social and environmental impacts or to understand the context in which given impacts arise. In this paper, we review and conceptualise the local impacts commonly cited in the literature and dissect the empirical evidence currently available to support their occurrence. Having assessed the quality of evidence and pinpointed knowledge gaps, we draw on methodological literature to identify approaches necessary to improve our understanding of the local impacts of CRE and explore their patterns of occurrence. We find a lack of robust survey and statistical evidence across all the seven impact categories identified. Of the impacts identified, ‘empowerment’ and ‘access to affordable energy’ are found to be the least studied. In addition, several impacts are associated only with specific types of community energy projects. We argue that the paucity of consistent evidence for direct impacts associated with the development processes and direct outcomes of projects suggests that the most substantial local impacts result from medium to long term indirect project outcomes and the investment of project revenues in the local community. As such, collective funding pools and negotiation processes around their distribution towards private versus public goods play a crucial role in determining transformative local impacts of CRE. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyse the environmental performances of three different extraction systems for forestry considering three different scenarios concerning the valorisation of forest residuals are analysed. The compared tree extraction systems are characterised by felling and processing performed with chainsaw and three different extraction methods: i) by farm tractor equipped with a winch; ii) by skidder and iii) by cable crane. The “Full Tree System” was adopted for all the felling sites; trees were felled and transported to roadside with branches and top intact. For wood chips produced from branches and tops, different scenarios were considered: heat and electricity generation and substitution of wood-chip production. To evaluate the environmental performance the Life Cycle Assessment (LCA) approach was applied. The selected functional unit (FU) is 1 m 3 of roundwood; the system boundary involves all the operations carried out in forestry (felling, bunching, extraction, processing, chipping of forest residuals), the transport of the produced wood chips and all the related inputs and emissions. A comparison with previously carried out studies in similar geographic areas were performed. The study's outcomes show how, the environmental results among the different logging systems are not univocal and the best logging system depends on the considered impact category. Though cable yarder is recognised as an extraction method able of reducing the physical impacts on residual stand (wounding) and soil (disturbance and compaction), for 10 of the 12 impact categories evaluated in this study, achieves the worst performances. The logging systems in which the extraction is performed using the tractor and the skidder show the best performance for 6 of the 12 evaluated impact categories. Finally, regarding wood residues utilisation and the impact of particulate matter formation, the energetic valorisation of wood chips does not involve any benefit but involves a worsening of the environmental performances due to wood combustion emissions. [ABSTRACT FROM AUTHOR]

Abstract: With rapid urbanization and industrialization, China has become both the largest energy consumer and CO2 emitting country in the world. As a clean and low-carbon energy source, renewable energy is a good choice to substitute for the exhausted fossil energy. The Chinese central and local governments have made a series of policies and optimistic plans to promote a rapid development of renewable energies. China′s renewable energy development has become a key to the sustainable development of socio-economic system. Unlike most of the current studies which mainly identified the challenges regarding policies and technologies around renewable energy or performed specific analyses for a certain kind of renewable energy, this paper summarizes the spatial disparity and consistency among the major renewable energies, coal resources, energy consumption and its major influencing factors in China, and reviews the positive and negative environmental impacts of major renewable energies. Based on the geographical and environmental perspectives, this paper recommends that the Chinese government: constructs the national energy production bases according to the resource distribution; integrates different energies on the basis of their natural features and spatial consistency; adjusts the overall layout of socio-economic development consistent with renewable energies; and promotes a moderate renewable energy development to maximize the environmental benefits. [Copyright &y& Elsevier]

Aqueous hybrid ion batteries (AHIB) are being promoted as an environmentally friendly alternative to existing stationary battery technologies. However, no quantification of their potential environmental impacts has yet been done. This paper presents a prospective life cycle assessment of an AHIB module and compares its performance with lithium-ion and sodium-ion batteries in two different stationary energy storage applications. The findings show that the claim of being an environmentally friendly technology can only be supported with some major limitations. While the AHIB uses abundant and non-toxic materials, it has a very low energy density and requires increased amounts of material for providing a given storage capacity. Per kWh of battery, results comparable to those of the alternative lithium- or sodium-ion batteries are obtained, but significantly higher impacts under global warming and ozone depletion aspects. The comparable high cycle life of the AHIB compensates this partially, requiring less battery replacements over the lifetime of the application. On the other hand, its internal inefficiencies are higher, what becomes the dominating factor when charging majorly fossil based electricity, making AHIB unattractive for this type of applications. [ABSTRACT FROM AUTHOR]

The decision-making process regarding the choice of alternative energy technologies is multidimensional, made up of a number of aspects at different levels, economic, technical, environmental and social. This paper uses a multicriteria decision making model, PROMETHEE II, to determine the best fuel mix for electricity generation in an isolated Greek island, Lesvos. Having analyzed the energy profile of the island, a set of 7 energy policy scenarios are determined and assessed against economic, technical, environmental and social criteria. The energy policy scenarios include the use of conventional fuels, wind energy and natural gas, in its liquid form, liquefied natural gas (LNG). Weighting of criteria is carried out according to three different perspectives, each one focusing on sustainability, economic and environmental/social benefits. Two sensitivity analyses are performed taking into account the fluctuations of the electricity demand and the fluctuations of the fuel prices. [ABSTRACT FROM AUTHOR]

Abstract: Global warming is attracting a growing interest worldwide for the generation of large-scale energy from renewable energy sources as it is free from greenhouse gas emissions. Wind energy is one of the most promising renewable energy sources due to its availability and low cost and due to the fact that it is more efficient and advanced in technology. Hence, harvesting of large-scale wind energy is of prime interest today. However, large-scale integration of wind energy sources creates environmental, economic, social and technical impacts that need to be investigated and mitigated as part of developing a sustainable power system for the future. Government, utilities and research communities are working together to increase penetration of wind energy into the power grid and overcome potential barriers associated with this. This paper presents an extensive and useful survey on wind energy technology and associated implementation issues including effects of wind farms on the nearby locality. This paper also reviews the social, environmental and cost-economic impacts of installing large-scale wind energy plants. Finally, potential technical challenges to the integration of large-scale wind energy into the power grid are reviewed in regard to current research with their available mitigation techniques. [Copyright &y& Elsevier]

The present study explores the implementation of district heating and cooling systems across a broad set of case studies reported in the literature. Topics addressed include their history, system identification, energy sources, design considerations, environmental impact, economic feasibility, performance analysis and the role of energy policy. The history of district heating and cooling systems reveals how available technology has influenced the configuration of district energy systems as more efficient and cleaner methods of providing heating and cooling have arisen. This leads to system identification based on primary energy sources, including the deployment of more and more renewable energy streams. Advantages and disadvantages of each energy source are examined in detail. Policies created by government and international entities will have a major impact on the future of research and development in district energy systems. Incentives may become necessary for creating favorable conditions for the efficient construction and utilization of district heating and cooling. Outcomes of these policies influence design considerations underlying any district energy system and their contribution in sustainability. Studies on greenhouse gas emissions along with the economic impacts of district energy construction are part of the design process and optimization of district energy systems should include economic and environmental considerations and not solely thermal efficiency. District heating and cooling systems are often integrated with components such as absorption chillers, cogeneration and thermal energy storage. Performance analysis using exergy and energy analysis have revealed several sources of irreversibility in district heating systems with these elements. If understood properly, these can greatly enhance system operation. Awareness and accommodation of the many factors discussed in this paper can improve the soundness of any district heating or cooling installation. [ABSTRACT FROM AUTHOR]

Abstract: It is usually mentioned that renewable energy sources (RES) have a large potential to contribute to the sustainable development of specific territories by providing them with a wide variety of socioeconomic benefits, including diversification of energy supply, enhanced regional and rural development opportunities, creation of a domestic industry and employment opportunities. The analysis of these benefits has usually been too general (i.e., mostly at the national level) and a focus on the regional and especially the local level has been lacking. This paper empirically analyses those benefits, by applying a conceptual and methodological framework previously developed by the authors to three renewable energy technologies in three different places in Spain. With the help of case studies, the paper shows that the contribution of RES to the economic and social dimensions of sustainable development might be significant. Particularly important is employment creation in these areas. Although, in absolute terms, the number of jobs created may not be high, it may be so with respect to the existing jobs in the areas considered. Socioeconomic benefits depend on several factors, and not only on the type of renewable energy, as has usually been mentioned. The specific socioeconomic features of the territories, including the productive structure of the area, the relationships between the stakeholders and the involvement of the local actors in the renewable energy project may play a relevant role in this regard. Furthermore, other local (socioeconomic) sustainability aspects beyond employment creation should be considered. [Copyright &y& Elsevier]

This paper applies a life cycle approach to evaluate for the first time the environmental impacts of renewable electricity in Turkey. There are 305 power plants utilising hydro, wind and geothermal resources, all of which are considered in the study. The results indicate that the impacts from large reservoir hydropower are lower than for the small reservoir (by 45%–72%) and run-of-river hydropower (by 74%–84%). The exceptions are the global warming potential (GWP) and summer smog which are two times and 45% higher for large than small reservoir, respectively. Onshore wind is the worst option overall, with nine out of 11 impacts higher than for hydropower and geothermal. However, its GWP is 9 times and 11% lower than for geothermal and large reservoir, respectively. Acidification from geothermal is 281 times higher than for wind power. Geothermal is the best option for six impacts. Large reservoir has the lowest depletion of elements and fossil resources as well as acidification. Small reservoir and run-of-river plants are the best and geothermal the worst options for the GWP. The majority of the annual impacts from the renewable electricity mix are from hydropower with the exception of acidification which is largely from geothermal electricity. [ABSTRACT FROM AUTHOR]

Global energy focus is turning more and more towards renewable energy. With legally binding agreements requiring a drastic increase in the percentage of national energy demand created with renewable sources, tidal energy holds an important advantage – predictability. The UK is fortunate, having the greatest potential for this energy in the world, which if exploited, would be able to provide approximately 20% of the national energy demand. The most discussed tidal energy site has been the Severn estuary barrage, with repeated proposals outlined and rejected throughout the last 100 years. The reasons for this refusal were due to both high costs and environmental concerns. However, a new proposal for a tidal lagoon in Swansea Bay has been able to circumnavigate both of these downfalls by reducing both the investment needed and effects to the surrounding environment. Subject to a tidal range of 10.5 m and situated next to a largely populated city with excellent grid connections, Swansea bay is a perfect location. If the lagoon project goes ahead, it would be able to produce a rated output of 320 MW using bulb turbines, powering 155,000 homes. Being the first tidal lagoon project, what is certain is: the UK and Wales in particular are sending out a strong message regarding renewable energy and it has the whole worlds attention. This paper sets out to bring together current literature regarding the planned Swansea Bay tidal lagoon into one concise document. [ABSTRACT FROM AUTHOR]

Wind has been the largest contributor to the growth of renewal energy during the early 21st century. However, the natural uncertainty that arises in assessing the wind resource implies the occurrence of wind power forecasting errors which perform a considerable role in the impacts and costs in the wind energy integration and its commercialization. The main goal of this paper is to provide a deeper insight in the analysis of timing errors which leads to the proposal of a new methodology for its control and measure. A new methodology, based on Dynamic Time Warping, is proposed to be considered in the estimation of accuracy as attribute of forecast quality. A new dissimilarity measure, the Temporal Distortion Index, among time series is introduced to complement the traditional verification measures found in the literature. Furthermore we provide a bi-criteria perspective to the problem of comparing different forecasts. The methodology is illustrated with several examples including a real case. [ABSTRACT FROM AUTHOR]

The potential for sugarcane ethanol from Brazil to mitigate GHG emissions is undeniable, but the way that ethanol is produced during the agricultural and industrial phases will ultimately determine its benefits to society. In this paper, we evaluate the environmental impacts of sugarcane agriculture and ethanol production in Brazil as management practices continue to change and production expands to new frontiers. We focused our evaluation on the impacts on water, atmosphere, and soils, including how the application of organic and inorganic fertilizers and the accumulation of crop residue in the field affect emissions of greenhouse gases (GHG). We also addressed the impacts of land use changes on threatened biomes and discussed some of the present obstacles regarding conservation and restoration efforts. We concluded that, since a similar assessment was put forth in 2008, our knowledge about the environmental impacts of sugarcane ethanol in Brazil has advanced with regard to soil degradation, nitrogen dynamics, and soil carbon stocks. However, more information is still needed about the impacts of the increasing use of pesticides, herbicides, and fertilizers in sugarcane agriculture, especially on water resources. Furthermore, without a better understanding about how landscape fragmentation affects the biodiversity of terrestrial and aquatic tropical ecosystems and the services they provide, policies created to protect and restore them may be ineffective. On the other hand, the use of presently available scientific information to end unsustainable farming and the implementation of conservation strategies proposed by the Brazilian Forest Code could be a first step to guarantee that ethanol is produced more sustainably in Brazil. [ABSTRACT FROM AUTHOR]

The future energy system in community level should be more ‘smart’ to secure reliability, enhance market service, minimize environmental impact, reduce costs and improve the use of renewable energy source (RES). Therefore, this paper proposes an energy integration system – smart hybrid renewable energy for communities (SHREC). It considers both thermal (heating and cooling) and electricity market in a large community level and highlight the interactions between them through utilizing RES, combined heat and power (CHP) and energy storages. A planning model based on CHP modelling is developed for the SHREC system. A linear programming (LP) algorithm is developed to optimize the SHREC system in a weekly period and the results are compared with an existing energy optimization software. We also demonstrate the model in a sample SHREC system during three typical weeks with cold, warm and mid-season weather in the year 2011. The results indicate that the developed modelling and optimization method is more efficient and flexible for the smart hybrid renewable energy systems. [ABSTRACT FROM AUTHOR]

Buildings significantly contribute to global environmental pollution due to consumption of both natural and primary-energy resources as well as to emission of carbon dioxide in their life-cycles. Therefore, to enable construction of more sustainable buildings, it is important and urgent that new low-environmental impact materials are developed, mainly by reducing the use of non-renewable resources. In this regard, the recent advances in the development of natural fibres represent a significant opportunity to produce improved-materials and energy from renewable resources. For this purpose, assessments of energy and environmental performances are needed to support both the design and the production of the aforementioned materials so as to identify solutions for enhanced contribution to global sustainability. In this context, this study presented a review of the papers published up to February 2015 that have been focussed upon the assessment of the environmental and energy impacts related to the use of hemp-based materials for building applications. The reviewed studies aimed at testing and improving hygro-thermal properties and eco-friendliness of these materials for reduction of both embodied and operational energy, whilst preserving both indoor air quality and comfort. Doing so would enable limiting the use of energy resources and, as a consequence, their impacts to human health and to the environment, so contributing to making buildings healthier and more environmentally sustainable throughout their life-cycles. Based upon the findings of the studies reviewed, these materials have strengths and weaknesses and their use is strictly dependent upon the given structural situation as well as upon specific requirements of thermal, moisture, fire and sound protection. In particular, all studies concluded that the main strength in the use of hemp-based materials comes from the production phase because of the “green” origin of these materials, mainly associated with the carbon sequestration during plantation growth. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology for designing a solar–biogas hybrid renewable energy system considering the integration of renewable energy's variability and its intermittency nature. It also studies for the first time the use of biogas to complement the unreliability of solar energy for a large-scale industry like mining, considering its unique characteristics. The proposed model minimizes annual costs and greenhouse gas emissions, configuring a hybrid renewable system that optimizes its usual economic benefits and defines its topology to improve the environmental impact while ensuring the energy demand. The results indicate that solar energy and biogas are attractive options to supply the electrical requirements of a copper mining process, as they bring economic and environmental benefits. However, a deeper environmental evaluation of the system is needed. The findings also show a trade-off between costs and greenhouse gas emissions; therefore, to promote the minimization of emissions in the system studied, the carbon tax price should be between 100–1,000 USD/ton CO 2 -eq. Finally, installing the proposed hybrid energy system could help reduce between 30% and 80% of the emissions compared to the actual scenario, and it could reduce around 50% of the total emissions in the next 30 years. • Renewable energy has a key role in the decarbonization of the cooper mining industry. • There is a trade-off between costs and GHG emissions. • A deeper analysis of the environmental impact of energy systems is needed. • A carbon tax between 100–1,000 USD/ton CO 2 -eq is needed to minimize GHG emissions. [ABSTRACT FROM AUTHOR]

Abstract: Renewable energy sources are widely perceived as ‘clean’, ‘green’, and ‘inexhaustible’. In recent years the spectre of global warming and ocean acidification, which has been primarily attributed to fossil fuel burning, has brought renewable energy at the forefront of most climate change mitigation strategies. There is strong advocacy for large-scale substitution of conventional energy sources with the renewables on the premise that such a move would substantially reduce environmental degradation and global warming. These sentiments are being echoed by scientists and policy makers as well as environmental activists all over the world. ‘Small hydro’, which generally represents hydroelectric power projects of capacities 25MW or lower, is one of the renewable energy options which is believed to be clean and sustainable even as its bigger version, large hydro, is known to cause several strongly adverse environmental impacts. This paper brings out that the prevailing perception of ‘eco-friendliness’ of small hydro is mainly due to the fact that it has only been used to a very small extent so far. But once it is deployed at a scale comparable to fossil fuel use, the resulting impacts would be quite substantially adverse. The purpose is not to denegrade small hydro, less so to advocate use of fossil fuels. It, rather, is to bring home the point that a much more realistic and elaborate assessment of the likely direct as well as indirect impacts of extensive utilization of this energy source than has been done hitherto is necessary. [Copyright &y& Elsevier]

Abstract: In an effort to diversify economies and reduce high oil dependency, the Gulf Cooperation Council (GCC) countries plan to increase the use of renewable energy sources to meet the challenges of a post-oil future. The Accession to the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol, which require a commitment to reduce greenhouse gas emissions, has started a process of environmental awakening in the GCC countries. This paper reviews the publications on renewable energy with reference to the GCC countries since 2005. The objective was to investigate the benefits of funding and investing in renewable energy projects in the GCC countries. The article shows that the GCC countries have begun to adopt a more pro-active approach toward renewable energy that will help progress the GCC countries towards sustainability. The reorientation of strategies and policies toward renewable energy is evolving in the GCC countries. [Copyright &y& Elsevier]

Abstract: Tidal energy has the potential to play a key role in meeting renewable energy targets set out by the United Kingdom (UK) government and devolved administrations. Attention has been drawn to this resource as a number of locations with high tidal current velocity have recently been leased by the Crown Estate for commercial development. Although tides are periodic and predictable, there are times when the current velocity is too low for any power generation. However, it has been proposed that a portfolio of diverse sites located around the UK will deliver a firm aggregate output due to the relative phasing of the tidal signal around the coast. This paper analyses whether firm tidal power is feasible with ‘first generation’ tidal current generators suitable for relatively shallow water, high velocity sites. This is achieved through development of realistic scenarios of tidal current energy industry development. These scenarios incorporate constraints relating to assessment of the economically harvestable resource, tidal technology potential and the practical limits to energy extraction dictated by environmental response and spatial availability of resource. The final scenario is capable of generating 17 TWh/year with an effective installed capacity of 7.8 GW, at an average capacity factor of 29.9% from 7 major locations. However, it is concluded that there is insufficient diversity between sites suitable for first generation tidal current energy schemes for a portfolio approach to deliver firm power generation. [Copyright &y& Elsevier]

Abstract: In promoting renewable energy options, the environmental problem of GHG emissions should not be replaced with other environmental problems. Large-scale renewable infrastructure projects in particular – from offshore wind farms to concentrated solar towers to hydropower installations – need to be accompanied by adequate environmental and social impact assessments. For policies, plans and programmes around renewable energy investments, strategic environmental assessments should be applied. Such assessments will increasingly need to consider the changing nature of supporting ecosystem services and the need for climate adaptation. Financing institutions should promote appropriate safeguards, supported by capacity building activities from international organizations, including IRENA, in order to unleash the full sustainable potential of renewable energy options. This paper explores the experiences of applying impact assessment tools and processes to renewable investments and highlights some of the key aspects which should be taken into consideration when pursuing a renewable energy future. [Copyright &y& Elsevier]

Abstract: Throughout the world, desalination is intensively used as a means to reduce current or future water scarcity, especially for the coastal areas. However, the dramatic increase in desalinated water supply will create a series of problems, the most significant of which are those related to energy consumption and environment impacts. Renewable energy provides an energy security and environmental friendly option simultaneously when decreasing global reserves of fossil fuels threatens the long-term sustainability of global economy. Thus, the integration of renewable resources in desalination and water purification is becoming increasingly attractive. In this paper an attempt has been made to present a review, in brief, work of the highlights that have been achieved during the recent years worldwide and the state-of-the-art for most important efforts in the field of desalination by wind energy, which is one of the most common form of renewable energies. The wind energy transform patterns, modeling and experimental studies of various wind energy powered desalination plant, and the prototypes established worldwide are majorly discussed. Moreover, two important technological problems in wind utilization are discussed, and the present or potential countermeasures for the intermittent characteristic and direct utilization of wind energy are presented. [Copyright &y& Elsevier]

Abstract: A development in wind energy technology towards higher nominal power of the wind turbines is related to the shift of the turbines to better wind conditions. After the shift from onshore to offshore areas, there has been an effort to move further from the sea coast to the deep water areas, which requires floating windmills. Such a concept brings additional environmental impact through higher material demand. To evaluate additional environmental burdens and to find out whether they can be rebalanced or even offset by better wind conditions, a prospective life cycle assessment (LCA) study of one floating concept has been performed and the results are presented in this paper. A comparison with existing LCA studies of conventional offshore wind power and electricity from a natural gas combined cycle is presented. The results indicate similar environmental impacts of electricity production using floating wind power plants as using non-floating offshore wind power plants. The most important stage in the life cycle of the wind power plants is the production of materials. Credits that are connected to recycling these materials at the end-of-life of the power plant are substantial. [Copyright &y& Elsevier]

Abstract: Conventional energy sources based on oil, coal, and natural gas have proven to be highly effective drivers of economic progress, but at the same time damaging to the environment and to human health. Keeping in mind, the social, economical and environmental effects of renewable energy system have been discussed in this paper. The uses of renewable energy system, instead of, conventional energy system, to control the social, economical and environmental problems have been discussed. The results show that the trends of total emission reduction in different years, which is exponentially increasing after the installation of renewable energy system in remote areas. [Copyright &y& Elsevier]

Abstract: Biodiesel is one of the candidates for alternative fuels since it is renewable, sustainable and produced from domestic or non-food crop resources with less detrimental environmental impact. There are several different approaches to the production process. In this paper a new production method, the supercritical methanol process, was investigated and its environmental performance was compared with the conventional alkali-catalyzed process using LCA as a tool. The supercritical process is technically a simpler production process and offers the advantages of higher yields and the production of less environmentally damaging wastes. However, it still generates a significantly higher environmental load since the methanol recovery unit requires a large amount of energy. [Copyright &y& Elsevier]

Abstract: Before new technologies enter the market, their environmental superiority over competing options must be asserted based on a life cycle approach. However, when applying the prevailing status-quo Life Cycle Assessment (LCA) approach to future renewable energy systems, one does not distinguish between impacts which are ‘imported’ into the system due to the ‘background system’ (e.g. due to supply of materials or final energy for the production of the energy system), and what is the improvement potential of these technologies compared to competitors (e.g. due to process and system innovations or diffusion effects). This paper investigates a dynamic approach towards the LCA of renewable energy technologies and proves that for all renewable energy chains, the inputs of finite energy resources and emissions of greenhouse gases are extremely low compared with the conventional system. With regard to the other environmental impacts the findings do not reveal any clear verdict for or against renewable energies. Future development will enable a further reduction of environmental impacts of renewable energy systems. Different factors are responsible for this development, such as progress with respect to technical parameters of energy converters, in particular, improved efficiency; emissions characteristics; increased lifetime, etc.; advances with regard to the production process of energy converters and fuels; and advances with regard to ‘external’ services originating from conventional energy and transport systems, for instance, improved electricity or process heat supply for system production and ecologically optimized transport systems for fuel transportation. The application of renewable energy sources might modify not only the background system, but also further downstream aspects, such as consumer behavior. This effect is, however, strongly context and technology dependent. [Copyright &y& Elsevier]