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The paper is aimed at studying the methodological aspects of assessing the features and advantages of implementing climate-neutral investment projects in the context of environmental protection and energy security. For this purpose, investigation is focused on the performance of investment projects in nature resource sectors (agriculture, forestry, etc.) that provide renewable resources (biomass) for the generation of green energy. The paper identifies the peculiarities of the transition to low-carbon economy and creation of carbon markets as platforms for the development of a system for managing climate-neutral investment projects. The scientific novelty of this research lies in the improvement of approaches to substantiating the economic feasibility of investments in nature resource sectors in view of the climate change. Namely, a comprehensive approach to comparing alternative variants of investment project solutions in climate- neutral projects is suggested. Moreover, the developed methodological recommendations account for the variable meteorological factors in calculating economic indicators. The paper's practical value can be seen in the determination of the benefits from the implementation of climate-neutral projects using the example of production and processing of the agro-biomass for the development of renewable energy based on the circular use of resources. [ABSTRACT FROM AUTHOR]

Combating global warming-related climate change demands prompt actions to reduce greenhouse gas emissions, particularly carbon dioxide. Biomass-based biofuels represent a promising alternative fossil energy source. To convert biomass into energy, numerous conversion processes are performed at high pressure and temperature conditions, and the design and dimensioning of such processes requires thermophysical property data, particularly thermal conductivity, which are not always available in the literature. In this paper, we proposed the application of Chemoinformatics methodologies to investigate the prediction of thermal conductivity for hydrocarbons and oxygenated compounds. A compilation of experimental data followed by a careful data curation were performed to establish a database. The support vector machine algorithm has been applied to the database leading to models with good predictive abilities. The support vector regression (SVR) model has then been applied to an external set of compounds, i.e. not considered during the training of models. It showed that our SVR model can be used for the prediction of thermal conductivity values for temperatures and/or compounds that are not covered experimentally in the literature. [ABSTRACT FROM AUTHOR]

The growing need for energy resources and the urgent needed action for climate change competing lead to conflict between all sectors on how to meet the needs without causing environmental degradation. By looking for alternatives source between the renewable resources? the best selection meets the needs is biofuel. Out of Biofuel types, Biodiesel is a great and clean selection of energy resources. Biodiesel prepared from many feedstocks to extract fatty acid from different generations of biodiesel, each generation has its limitation thought looking for viable and cost-effective feedstock? In this paper we discuss the use of agricultural waste as feedstock for biodiesel preparation using oleaginous fungi as mini-factories. [ABSTRACT FROM AUTHOR]

Increasing emissions of greenhouse gases and increasing prices for fossil fuels have highlighted the demand for CO2 "neutral" renewable energy sources, e.g. short rotation forestry systems used for bioenergy. These systems might be vulnerable to changes in temperature, precipitation and occurrence of extreme weather events. To estimate success or failure of such short rotation coppices in a certain area we need regional climate projections and risk assessment. Changes of water supply patterns in two agriculturally extensively used regions in Central Germany (around Göttingen and Großfahner) with different climate conditions but both in the temperate climate zone are explored. The study is carried out under present conditions as well as under projected climate change conditions (1971-2100) using A1B and B1 climate scenarios downscaled for Europe. Analysis of precipitation bias shows regional differences: a strong bias in Göttingen area and a weaker bias in the Großfahner area. A bias correction approach, Quantile mapping, is applied to the ensemble results for both areas for winter and summer seasons. By using quantile regression on the seasonal Standardized Precipitation Indices (SPIs) as indicator for water supply conditions we found that precipitation is expected to increase in winter in all quantiles of the distribution for Göttingen area during the 21th century. Heavy precipitation is also expected to increase for Großfahner area suggesting a trend to wetter extremes in winter for the future. This winter precipitation increase could trigger runoff and soil erosion risk enhancing the severity of floods. Increasing winter availability of water could enhance local water supply in spring. For both areas no significant change in summer was found over the whole time period. Although the climate change signal of the SPI indicate mild dryer conditions in summer at the end of the 21st century which may trigger water shortage and summer drying associated with above--average temperatures in the future. Even though both study areas are close together Großfahner area was found to be the least affected one by changes indicating that small spatial scale differences matter. These developments were found in all examined simulation runs. This study highlighted the regional differences in the vulnerability to water surplus or deficit risks in a temperate system which emphasizes the need in impact studies to focus on proper consideration of local and regional environmental conditions as well as adaption and mitigation of management for agriculture. [ABSTRACT FROM AUTHOR]

Biomass use for energy and materials is, on the one hand, one of the key mitigation options to reach the 1.5 °C GMT target set in the Paris Agreement, as highlighted by the IPCC and many other key analyses. On the other hand, particularly in parts of the EU, a strong negative connotation has emerged in public debate and EC policy, with a particular emphasis on the (presumed) displacement effect in markets and land use. This is a remarkable contrast because the reasons to use sustainable biomass, on the one hand, and the possibilities and synergies for supplying sustainable biomass, on the other, are underpinned with strong evidence, also providing insights on how displacement issues can be avoided. Sustainable biomass supplies can contribute 20–30% of the future global and European energy supply, leading to reduced overall mitigation costs, including realizing the net CO2 removal from the atmosphere using BECCS concepts. This paper highlights which options, pathways and preconditions are key to achieving such a substantial contribution of sustainable biomass in future (2050) energy and material supply (with a focus on the European setting). By pinpointing how "biomass can be done right" and how important synergies can be achieved via better agricultural methods, the restoration of marginal and degraded lands and the adaptation of climate change, a different policy agenda emerges in sharp contrast to how a biobased economy has been framed in recent years. It is recommended that future policy priorities, particularly at the EU level, take a more integral view on the synergy between the role of biomass in the energy transition, climate adaptation and mitigation, better agriculture and the better use of land in general. Strategies to achieve such positive results typically require an alignment between renewable energy, and agricultural, environmental, mitigation and adaptation policies, which is a largely missing nexus in different policy arenas. Resolving this lack of alignment offers a major opportunity, globally, to contribute to the European Green deal and improve energy security. [ABSTRACT FROM AUTHOR]

Biofuels are currently at the centre stage of attention for policy makers and climate concerned end-users seeking more sustainable energy source for sustainable environment. This is because of its potential as an alternative and/or cleaner source of energy. However, questions are being raised about the capability of biofuels to achieve the dual goal of environmental and energy security without jeopardizing global food security. To set realistic target for future biofuel options, it is important to assess biofuel sustainability based on their prospects and implications on critical emerging issues such as energy supply security, climate change mitigation, biodiversity and ecosystem preservation, and food security. This paper presents a review of different governance approaches undertaken by the key actors in the biofuel industry (U.S. and EU) to address these emerging issues and regulate the sustainability of biofuel production. Two of such programmes were examined - The United States Renewable Fuel Standard [U.S. RFS], and the European Union Renewable Energy Directive [EU-RED]. Efforts were made to examine the related environmental and economic implications of their policy initiatives and governance processes with a view to determining their outcomes across a wide range of stakeholders. Emphasis was placed on binding regulations and standardized mechanisms of bilateral and multi-lateral agreements at the global level. [ABSTRACT FROM AUTHOR]

The challenges caused by climate change are becoming inevitable. The main cause is represented by human activities, which are associated with the overexploitation of ecosystem services and natural resources, to meet the ever-growing demand for human needs. This leads to extensive environmental degradation and the release of greenhouse gases into the atmosphere, leading to a dangerous increase in the global average temperature. The benefits of biofuels compared to traditional fuels aim at greater energy security, lower environmental impact, financial savings and socioeconomic aspects related to the rural sector. The concept of sustainable development embodies the idea of inter-connectivity and balance between economic, social and environmental concerns. Romania relies heavily on biomass for the contribution of energy from renewable sources in this sector, biomass being generally used more in rural areas. [ABSTRACT FROM AUTHOR]

Copyright of Ecological Chemistry & Engineering S / Chemia i Inzynieria Ekologiczna S is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research aims to identify and evaluate the key challenges and obstacles hindering the adoption of sustainable energy in the aviation industry. The outcomes and insights derived from this research will be synthesized to provide a comprehensive overview of the opportunities and suggestions for the adoption of sustainable energy in the aviation industry. The objective of this study is to help the aviation industry's shift toward more sustainable energy sources in order to reduce its environmental footprint and mitigate the effects of climate change. [ABSTRACT FROM AUTHOR]

Purpose: The increasing concern for adverse effects of climate change has spurred the search for alternatives for conventional energy sources. Life cycle assessment (LCA) has increasingly been used to assess the potential of these alternatives to reduce greenhouse gas emissions. The popularity of LCA in the policy context puts its methodological issues into another perspective. This paper discusses how bio-electricity directives deal with the issue of allocation and shows its repercussions in the policy field. Methods: Multifunctionality has been a well-known problem since the early development of LCA and several methods have been suggested to deal with multifunctional processes. This paper starts with a discussion of the most common allocation methods. This discussion is followed by a description of bio-energy policy directives. The description shows the increasing importance of LCA in the policy context as well as the lack of consensus in the application of allocation methods. Methodological differences between bio-energy directives possibly lead to different assessments of bio-energy chains. To assess the differences due to methodological choices in bio-energy directives, this paper applies three different allocation methods to the same bio-electricity generation system. The differences in outcomes indicate the importance of solving the allocation issue for policy decision making. Results and discussion: The case study focuses on bio-electricity from rapeseed oil. To assess the influence of the choice of allocation in a policy directive, three allocation methods are applied: economic partitioning (on the basis of proceeds), physical partitioning (on the basis of energy content), and substitution (under two scenarios). The outcomes show that the climate change score is assessed quite differently; ranging from 0.293 kg to 0.604 kg CO eq/kWh. It is argued that this uncertainty hampers the optimal use of LCA in the policy context. The aim of policy LCAs is different from the aim of LCAs for analysis. Therefore, it is argued that LCAs in the policy context will benefit from a new guideline based on robustness. Conclusions: The case study confirms that the choice of allocation method in policy directives has large influence on the outcomes of an LCA. With the growing popularity of LCA in policy directives, this paper recommends a new guideline for policy LCAs. The high priority of robustness in the policy context makes it an ideal starting point of this guideline. An accompanying dialog between practitioners and commissioners should further strengthen the use of LCA in policy directives. [ABSTRACT FROM AUTHOR]

The paper outlines EU policy on bioenergy, including biofuels, in the context of its policy initiatives to promote renewable energy to combat greenhouse gas emissions and climate change. The EU’s Member States are responsible for implementing EU policy: thus, the UK’s Renewables Obligation on electricity suppliers and its Renewable Transport Fuel Obligation and road-fuel tax rebates are examined. It is unlikely that EU policy is in conflict with the WTO Agreement on Agriculture or that on Subsidies and Countervailing Measures, but its provisions on environmental sustainability criteria could be problematic. [ABSTRACT FROM AUTHOR]

The paper promotes bioliquids from indigenous oil-rich plants as renewable energy sources. In the first part the paper analyzes the national and European perspectives to develop renewable energy sources according to the National Strategy for 2016 -2030 with the prospect of 2050, as per European directives. The second part presents the point of view of the Directive 2009/28/EC on bioliquids and the possibility to use bioliquids from oil-rich plants for energy generation in order to reduce pollutant emissions. The third part of this paper presents the results of laboratory analyses concerning the energy characteristics of bioliquids from indigenous oil-rich plants. The conclusions of part four point out that bioliquids from oil-rich plants have the potential to be a solution for EU's renewable energy and the climate change objectives. [ABSTRACT FROM AUTHOR]

The current concern about the climate change and the need for sustainable alternatives to fossil fuels has moved the European Union to establish objectives regarding the environment and renewable energy sources by 2020. Forest biomass is an alternative energy resource with an important role in the fulfillment of these objectives. This paper analyzes the possibilities of its implementation in Spain. Forest biomass resources have been analyzed with the BIORAISE application. Potential biomass is mapped considering local collection nodes by province, as well as available biomass, total cost (the sum of harvesting and transport costs), and energetic content ratio of the available biomass. The results show that Huesca and Cuenca are the two provinces with the most available biomass, while Pontevedra and Vizcaya have the highest energetic content ratio. The average total cost of biomass in Spain is 72.72 €/o.d.t., which is lower than the average cost of the supply of pellets to Pellet plants in Europe. Baleares and Huelva are the provinces which have the lowest potential cost of forest biomass. Savings between 48 and 81 % can be obtained using the available forest biomass for domestic heating compared to the other main systems. [ABSTRACT FROM AUTHOR]

Without a shift to renewable energy sources, climate change will have adverse effects on many terrestrial and aquatic species. On the other hand, replacing fossil fuels with renewable energy will have different effects on wildlife, some negative. To protect biota, while navigating the complexities surrounding the transition to renewable energy, will require sharing knowledge between energy experts and wildlife experts, as well as policy makers and resource managers. This special issue is intended to advance the conversation. Interactions between renewable energy facilities and fauna are complex. Each source of renewable energy has its own conservation concerns, and each presents its own set of opportunities for mitigation; Other concerns and mitigations are shared. In this overview, we review climate risks to biota, clarify the complementarities among renewables for the conservation community, and summarize research on energy effects on biota for the energy community. The papers invited for this special issue address fossil (coal, oil, natural gas) and renewable energy (terrestrial biomass energy, hydropower, marine-hydrokinetic energy, wind energy, solar energy) and affected fauna. We hope that the results of these studies, and others like them, set us on a path toward low-carbon energy systems that provide society with energy while protecting future biodiversity. [Display omitted] • Without a shift to renewable energy, climate change will have adverse effects on many terrestrial and aquatic species. • On the other hand, renewable energy sources have their own conservation concerns. • To set the stage for the special issue, we review growth projections and describe complementarities among renewables. • We summarize the conservation concerns and mitigations for each renewable energy source presented in special issue papers. • This special issue seeks to illuminate paths that provide society with energy while protecting future biodiversity. [ABSTRACT FROM AUTHOR]

Abstract: Black liquor gasification (BLG) for bio-fuel or electricity production at the modern pulp mills is a field in continuous evolution and the efforts are considerably driven by the climate change, fuel security, and renewable energy. This paper evaluates and compares two BLG systems for methanol production: (i) oxygen blown pressurized thermal BLG; and (ii) dry BLG with direct causticization, which have been regarded as the most potential technology candidates for the future deployment. A key objective is to assess integration possibilities of BLG technologies with the reference Kraft pulp mill producing 1000air dried tonnes (ADt) pulp/day replacing conventional recovery cycle. The study was performed to compare the systems’ performance in terms of potential methanol production, energy efficiency, and potential CO2 reductions. The results indicate larger potential of black liquor conversion to methanol from the pressurized BLG system (about 77million tonnes/year of methanol) than the dry BLG system (about 30million tonnes/year of methanol) utilizing identical amount of black liquor available worldwide (220million tDS/year). The potential CO2 emissions reduction from the transport sector is substantially higher in pressurized BLG system (117million tonnes/year CO2 reductions) as compared to dry BLG system (45million tonnes/year CO2 reductions). However, the dry BLG system with direct causticization shows better results when considering consequences of additional biomass import. In addition, comparison of methanol production via BLG with other bio-refinery products, e.g. hydrogen, dimethyl ether (DME) and bio-methane, has also been discussed. [Copyright &y& Elsevier]

Copyright of Brazilian Journal of Wood Science / Revista Ciência da Madeira is the property of Brazilian Journal of Wood Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Comparative analysis of the energy and carbon balances of wood vs. non-wood products is a complex issue. In this paper we discuss the definition of an appropriate functional unit and the establishment of effective system boundaries in terms of activity, time and space, with an emphasis on the comparison of buildings. The functional unit can be defined at the level of building component, complete building, or services provided by the built environment. Energy use or carbon emissions per unit of mass or volume of material is inadequate as a functional unit because equal masses or volumes of different materials do not fulfil the same function. Activity-based system boundaries include life cycle processes such as material production, product operation, and post-use material management. If the products compared are functionally equivalent, such that the impacts occurring during the operation phase are equal, we suggest that this phase may be dropped from the analysis allowing a focus on material flows. The use of wood co-products as biofuel can be analytically treated through system expansion, and compared to an alternative of providing the same energy service with fossil fuels. The assumed production of electricity used for material processing is another important energy-related issue, and we suggest that using marginal production data is more appropriate than average production. Temporal system boundaries include such aspects of the wood life cycle as the dynamics of forest growth including regeneration and saturation, the availability of residue biofuels at different times, and the duration of carbon storage in products. The establishment of spatial boundaries can be problematic, because using wood-based materials instead of non-wood materials requires more land area to capture solar energy and accumulate biomass. We discuss several possible approaches to meet this challenge, including the intensification of land use to increase the time rate of biomass production. Finally, we discuss issues related to scaling up an analysis of wood substitution from the micro-level to the macro-level of national, regional or global. [ABSTRACT FROM AUTHOR]

Abstract: India''s energy challenges are multi-pronged. They are manifested through growing demand for modern energy carriers, a fossil fuel dominated energy system facing a severe resource crunch, the need for creating access to quality energy for the large section of deprived population, vulnerable energy security, local and global pollution regimes and the need for sustaining economic development. Renewable energy is considered as one of the most promising alternatives. Recognizing this potential, India has been implementing one of the largest renewable energy programmes in the world. Among the renewable energy technologies, bioenergy has a large diverse portfolio including efficient biomass stoves, biogas, biomass combustion and gasification and process heat and liquid fuels. India has also formulated and implemented a number of innovative policies and programmes to promote bioenergy technologies. However, according to some preliminary studies, the success rate is marginal compared to the potential available. This limited success is a clear indicator of the need for a serious reassessment of the bioenergy programme. Further, a realization of the need for adopting a sustainable energy path to address the above challenges will be the guiding force in this reassessment. In this paper an attempt is made to consider the potential of bioenergy to meet the rural energy needs: (1) biomass combustion and gasification for electricity; (2) biomethanation for cooking energy (gas) and electricity; and (3) efficient wood-burning devices for cooking. The paper focuses on analysing the effectiveness of bioenergy in creating this rural energy access and its sustainability in the long run through assessing: the demand for bioenergy and potential that could be created; technologies, status of commercialization and technology transfer and dissemination in India; economic and environmental performance and impacts; bioenergy policies, regulatory measures and barrier analysis. The whole assessment aims at presenting bioenergy as an integral part of a sustainable energy strategy for India. The results show that bioenergy technology (BET) alternatives compare favourably with the conventional ones. The cost comparisons show that the unit costs of BET alternatives are in the range of 15–187% of the conventional alternatives. The climate change benefits in terms of carbon emission reductions are to the tune of 110T C per year provided the available potential of BETs are utilized. [Copyright &y& Elsevier]

Abstract: This special issue of the Journal of Cleaner Production focuses on “Energy for Sustainable Future”. It is designed to mirror the increasing relevance of renewable energy sources and improved efficiency as crucial topics for practitioners in industry, for governmental policy makers, as well as for civic service providers, researchers, and educators. The purpose of this special issue is to serve as a catalyst for dialogue. The global warming related to CO2 emissions, coupled with steeply rising energy prices and the recent global financial institutional melt-down are causing massive societal concerns and give rise to increasing demand for ways to improve societal and individual energy efficiency and for ways to shift increasingly to alternative, low or non-carbon based energy systems. Until recently, industrial energy efficiency improvements have focused on improvements on efficiency rather than on the integration of renewable sources. The aim of this special issue is the identification of policies to support the development and implementation of technologies and management approaches we can employ to make the transition to more sustainable societies. The collection of papers in this special issue provide a foundation for students, researchers, scholars, practitioners and policy makers interested in making sustainable development more than a metaphor. The papers include focus upon ways for: [(a)] Improving industrial process to achieve improvements in energy efficiency. [(b)] Minimising waste disposals and reducing their impact through better management. [(c)] Reducing CO2 emissions by making progress toward lower carbon, renewable energy based systems, [(d)] Improving production of biofuels and hydrogen production systems, facilitated by employing cleaner production and novel LCA tools. [(e)] Improving integration of advanced materials and energy efficient equipment in different industrial sectors. Current and future developments in national and world economies are closely connected to sustainable, efficient and safe usage of raw materials and upon energy based on cleaner production concepts and approaches that are ecologically and economically appropriate for the short and for the long-term future of society. These challenges have received considerable attention in the media and scientific journals over the last several years. The idea of developing a specialised conference focussed upon them was put forward on various occasions. Focus upon them became reality on the 5th and 6th May 2008 in the historic Castle of Veszprém, Hungary, the current premises of the Hungarian Academy of Science which hosted the Workshop. The Workshop was a stimulating event and an overwhelming success, with nearly 100 contributors from Africa, North America, Asia and Europe, representing 28 countries. After a comprehensive selection and thorough reviewing procedure 11 papers were selected for this special issue. [Copyright &y& Elsevier]

Biomass, a basic product of agriculture, is one of the main sinks of carbon in global cycle. Additionally, it can be used as a renewable source of energy, leading to depletion in CO2 emissions. The paper presents the results of estimations on the current and potential share of catch crop cultivation in climate change mitigation, in Poland, where the agricultural sector plays a significant economic role. The estimation of CO2 assimilation in biomass was performed on the basis of our own data on yields of commonly used catch crops, obtained in randomly selected 80 farms in Poland, and the content of carbon in the biomass. Calculation of energy potential of the biomass was conducted, assuming its conversion into biogas, on the basis of our own data on catch crop yields and the literature data on their biomethane potentials. The results have shown that catch crops in Poland, which are cultivated to an area of 1.177 mln ha sequestrate 6.85 mln t CO2 yr−1. However, considering the total area of fields used for spring crop cultivation, it is possible to increase the sequestration to 18.25 mln t CO2 yr−1, which constitutes about 6% of the annual emission of CO2 in Poland. Biomethane yields per hectare of particular crops ranged from 965 to 1762 m3 CH4 ha−1, and were significantly lower compared to maize, which is commonly in use in biogas plants. However, due to high biomethane potential and favorable chemical composition, catch crops can be a valuable co-substrate for the feedstocks with a high C:N ratio. The potential recovery of energy produced from aboveground biomass of catch crops harvested in Poland during the year is 6327 GWh of electricity and 7230 GWh of thermal energy. Thus, it is advisable to promote catch crops on a wide scale due to substantial environmental benefits of their cultivation. [ABSTRACT FROM AUTHOR]

Energy derived from fossil fuels contributes significantly to global climate change, accounting for more than 75% of global greenhouse gas emissions and approximately 90% of all carbon dioxide emissions. Alternative energy from renewable sources must be utilized to decarbonize the energy sector. However, the adverse effects of climate change, such as increasing temperatures, extreme winds, rising sea levels, and decreased precipitation, may impact renewable energies. Here we review renewable energies with a focus on costs, the impact of climate on renewable energies, the impact of renewable energies on the environment, economy, and on decarbonization in different countries. We focus on solar, wind, biomass, hydropower, and geothermal energy. We observe that the price of solar photovoltaic energy has declined from $0.417 in 2010 to $0.048/kilowatt-hour in 2021. Similarly, prices have declined by 68% for onshore wind, 60% for offshore wind, 68% for concentrated solar power, and 14% for biomass energy. Wind energy and hydropower production could decrease by as much as 40% in some regions due to climate change, whereas solar energy appears the least impacted energy source. Climate change can also modify biomass productivity, growth, chemical composition, and soil microbial communities. Hydroelectric power plants are the most damaging to the environment; and solar photovoltaics must be carefully installed to reduce their impact. Wind turbines and biomass power plants have a minimal environmental impact; therefore, they should be implemented extensively. Renewable energy sources could decarbonize 90% of the electricity industry by 2050, drastically reducing carbon emissions, and contributing to climate change mitigation. By establishing the zero carbon emission decarbonization concept, the future of renewable energy is promising, with the potential to replace fossil fuel-derived energy and limit global temperature rise to 1.5 °C by 2050. [ABSTRACT FROM AUTHOR]

Globally, nations are trying to address environmental issues such as global warming and climate change, along with the burden of declining fossil fuel reserves. Furthermore, countries aim to reach zero carbon emissions within the existing and rising global energy crisis. Therefore, bio-based alternative sustainable feedstocks are being explored for producing bioenergy. One such renewable energy resource is microalgae; these are photosynthetic microorganisms that grow on non-arable land, in extreme climatic conditions, and have the ability to thrive even in sea and wastewater. Microalgae have high photosynthetic efficiencies and biomass productivity compared to other terrestrial plants. Whole microalgae biomass or their extracted metabolites can be converted to various biofuels such as bioethanol, biodiesel, biocrude oil, pyrolytic bio-oil, biomethane, biohydrogen, and bio jet fuel. However, several challenges still exist before faster and broader commercial application of microalgae as a sustainable bioenergy feedstock for biofuel production. Selection of appropriate microalgal strains, development of biomass pre-concentrating techniques, and utilization of wet microalgal biomass for biofuel production, coupled with an integrated biorefinery approach for producing value-added products, could improve the environmental sustainability and economic viability of microalgal biofuel. This article will review the current status of research on microalgal biofuels and their future perspective. [ABSTRACT FROM AUTHOR]

The opportunity for renewable energy production in developing countries is a theme of high relevance within the context of climate change. In this paper we explore the production of electricity in Brazil and investigate the potential for sustainable biomass energy production. This is explored in a GIS system (1) establishing the demand centers or regions (energy demand factor), (2) checking if they can be served by existing capacity and transmission (transmission lines factor), (3) deciding on new generation and whether it will an island or the main grid connection (power plants factor), (4) locating the power plant subject to the potential biomass supply accepting the environmental constraints (land use and environmental preservation factors). Results show that even though large areas have a potential for biomass energy production, the lack of investments in technological improvements and changes in the system status quo result in a system that does not progress towards of becoming a cleaner, safer and less dependent on climatic factors. We conclude that biomass has the potential to grow as a source of renewable and clean energy. This potential can be explored by conserving respecting the environment and encouraging the creation of decentralized systems, thereby making Brazil a key player in the climate change targets in the coming years. [ABSTRACT FROM AUTHOR]

With the arising of global climate change and resource shortage, in recent years, increased attention has been paid to environmentally friendly materials. Trees are sustainable and renewable materials, which give us shelter and oxygen and remove carbon dioxide from the atmosphere. Trees are a primary resource that human society depends upon every day, for example, homes, heating, furniture, and aircraft. Wood from trees gives us paper, cardboard, and medical supplies, thus impacting our homes, school, work, and play. All of the above-mentioned applications have been well developed over the past thousands of years. However, trees and wood have much more to offer us as advanced materials, impacting emerging high-tech fields, such as bioengineering, flexible electronics, and clean energy. Wood naturally has a hierarchical structure, composed of well-oriented microfibers and tracheids for water, ion, and oxygen transportation during metabolism. At higher magnification, the walls of fiber cells have an interesting morphology--a distinctly mesoporous structure. Moreover, the walls of fiber cells are composed of thousands of fibers (or macrofibrils) oriented in a similar angle. Nanofibrils and nanocrystals can be further liberated from macrofibrils by mechanical, chemical, and enzymatic methods. The obtained nanocellulose has unique optical, mechanical, and barrier properties and is an excellent candidate for chemical modification and reconfiguration. Wood is naturally a composite material, comprised of cellulose, hemicellulose, and lignin. Wood is sustainable, earth abundant, strong, biodegradable, biocompatible, and chemically accessible for modification; more importantly, multiscale natural fibers from wood have unique optical properties applicable to different kinds of optoelectronics and photonic devices. Today, the materials derived from wood are ready to be explored for applications in new technology areas, such as electronics, biomedical devices, and energy. The goal of this study is to review the fundamental structures and chemistries of wood and wood-derived materials, which are essential for a wide range of existing and new enabling technologies. The scope of the review covers multiscale materials and assemblies of cellulose, hemicellulose, and lignin as well as other biomaterials derived from wood, in regard to their major emerging applications. Structure--properties-- application relationships will be investigated in detail. Understanding the fundamental properties of these structures is crucial for designing and manufacturing products for emerging applications. Today, a more holistic understanding of the interplay between the structure, chemistiy, and performance of wood and wood-derived materials is advancing historical applications of these materials. This new level of understanding also enables a myriad of new and exciting applications, which motivate this review. There are excellent reviews already on the classical topic of woody materials, and some recent reviews also cover new understanding of these materials as well as potential applications. This review will focus on the uniqueness of woody materials for three critical applications: green electronics, biological devices, and energy storage and bioenergy. [ABSTRACT FROM AUTHOR]

The urgent demand for alternative energy sources has been sparked by the tremendous burden on fossil fuels and the resulting acute energy crisis and climate change issues. Lignocellulosic biomass is a copious renewable and alternative bioresource for the generation of energy fuels and biochemicals in biorefineries. Different pretreatment strategies have been established to overcome biomass recalcitrance and face technological challenges, such as high energy consumption and operational costs and environmental hazards, among many. Biological pretreatment using microbial enzymes is an environmentally benign and low-cost method that holds promising features in the effective pretreatment of lignocellulosic biomass. Due to their versatility and eco-friendliness, cellulases, hemicellulases, and ligninolytic enzymes have been recognized as "green biocatalysts" with a myriad of industrial applications. The current review provides a detailed description of different types of lignocellulolytic enzymes, their mode of action, and their prospective applications in the valorization of lignocellulosic biomass. Solid state fermentation holds great promise in the microbial production of lignocellulolytic enzymes owing to its energy efficient, environment friendly, and higher product yielding features utilizing the lignocellulosic feedstocks. The recent trends in the application of enzyme immobilization strategies for improved enzymatic catalysis have been discussed. The major bottlenecks in the bioprocessing of lignocellulosic biomass using microbial enzymes and future prospects have also been summarized. [ABSTRACT FROM AUTHOR]

Most climate change mitigation scenarios rely on the incremental use of biomass as energy feedstock. Therefore, increasing the share of alternative sustainable energy sources as biomass is crucial to provide both peak and base electricity loads in future scenarios. The bioenergy potential of Ecuador has been addressed for agricultural by-products but not for dedicated bioenergy crops. Agricultural zoning studies have been developed for food crops but not for energy crops. Currently, the bioenergy share of electricity produced in Ecuador (1.4%) comes mainly from the use of sugar cane bagasse from sugar production. This study aims to identify potential sustainable bioenergy resources for continental Ecuador using agroecological zoning methodologies and considerations regarding land management, food security, in-direct land use change and ecological and climate change risks. The results identified 222,060.71 ha available to grow dedicated bioenergy crops and potential electricity production of 8603 GWh/year; giant reed ranks first with a potential net energy yield of 4024 GWh per year, and Manabí province presents the highest potential with 3768 GWh/year. Large-scale deployment of bioenergy in Ecuador would require the study of sustainability considerations of each project. The species studied are traditional bioenergy crops; research on novel species is encouraged. [ABSTRACT FROM AUTHOR]

In an effort to reduce CO 2 emissions from fossil fuel burning, renewable energy policies incentivize use of forest biomass as an energy source. Many governments have assumed (legislated) the carbon flux from burning biomass to be neutral because biomass growth sequesters CO 2 . Yet, trees take decades to recover the CO 2 released by burning, so assumed emissions neutrality (or near neutrality) implies that climate change is not considered an urgent matter. As biomass energy continues to be a significant strategy for transitioning away from fossil fuels, this paper asks the question: To what extent should we value future atmospheric carbon removals? To answer this, we examine the assumptions and pitfalls of biomass carbon sequestration in light of its increasing use as a fossil-fuel alternative. This study demonstrates that the assumed carbon neutrality of biomass for energy production hinges on the fact that we weakly discount future removals of carbon, and it is sensitive to tree species and the nature of the fuel for which biomass substitutes. [ABSTRACT FROM AUTHOR]

Triggered by debates on climate change and energy security, renewable energy sources are presently high on the political agenda in many countries. In this regard Russia seems to stand aside worldwide developments. Until recently Russia׳s enormous potential in renewable energy sources remained poorly utilised. However, Russia׳s formal commitment to the global climate change regime, its new Energy Strategy 2030, and an increase in wood pellet production suggest a discontinuity. This paper investigates and explains the (limited) progress in the solid bioenergy sector in Northwest Russia. With little Russian experience in this sector, poor technological knowledge on renewables, and inadequate domestic market structures, the development of a domestic solid bioenergy sector is far from easy. Hence, Northwest Russian wood pellet developments cannot be traced back to new federal policies, only partly to local demand and stimulation, and significantly to foreign drivers. Major EU demand for wood pellets and intensified collaboration with foreign companies and organisations leading in the field of solid bioenergy research, technology and trade have triggered these developments. But it is a long way before Russia will be released from its fossil fuel addiction, as repeatedly promised by governmental officials. [ABSTRACT FROM AUTHOR]

The eu regulatory framework for sustainable biofuels is an example of today's dynamic European climate and energy governance. The article demonstrates that there are, however, particular internal controversies that continue to undermine the overall credibility of the eu biofuel regime, as well as the effectiveness and legitimacy of the scheme. In connection with the debate on new governance, the article explores the concepts of input and output legitimacy as regards the verification of compliance with biofuel sustainability criteria. The article shows that if the procedural requirements to satisfy input legitimacy are not met, there is a risk that output legitimacy--the credibility of the substantive outcome--will also be diminished. By paying attention to the process and harmonizing the itemized process-related elements we can improve both the appropriate achievement of the substantive outcome as well as the legitimacy of eu biofuel governance. [ABSTRACT FROM AUTHOR]

Abstract: The most alarming feature today is how to manage the energy demand and crucial climate change. To run life among these major threats, a good idea is to penetrate renewable energy sources gradually into the global energy market. These renewables are the best alternative to conventional fuels because of their abundant potential, non-pollutant nature and are exceedingly eco-friendly with the environment. The major renewables include wind, solar and diesel energy sources with a safety battery back-up to challenge the energy disaster to a possible extent. In addition, minor sources like fuel cells, biomass and tidal energy can also be included if the load demand is high. The careful blending of these available resources and technologies facilitate economic and environmental benefits. This paper overviews the performance analysis of hybrid power systems, control methodologies and modeling techniques so as to get an optimum output power. [Copyright &y& Elsevier]

Abstract: Modern agriculture is heavily based on the energy supply obtained mainly from fossil fuels. In this sense, it can be defined as a technology that transforms fossil fuels into food. However, the available amount of fossil hydrocarbons is not infinite and climate change is creating a critical necessity of reducing their use. Therefore, it is not too early to start considering how agriculture could be adapted to sustainable sources of energy which do not cause climate change. In the present paper, we discuss how agriculture could be restructured in order to utilize the electric power provided by renewable energy technologies such as wind and photovoltaics. In this sense, the problem can be stated as the need of developing technologies able to turn electricity into food. In our analysis, we find that renewable electric power could provide some of the services for the farm produced today by fossil fuels at costs which are not outside reasonable ranges. However, not all the problems of modern agriculture can be solved simply shifting from one power source to another and the limited availability of mineral fertilizers, such as phosphates, remains a fundamental limitation. We conclude that renewable electric power in the farm should be seen as part of a more general transition that will require considerable transformations and adaptation of the current agricultural process in order to develop a truly sustainable agriculture. [Copyright &y& Elsevier]

Abstract: Considerable research is currently being devoted to seeking alternative fuels to comply with transportation needs while reducing the environmental impact of this sector. Within the transport activity sector, on road vehicles and agricultural machinery require around 2Mtoe energy in France. The anaerobic digestion of farm waste could roughly cover these needs. This paper aims to study the environmental and energy interest of this short power supply path. An ideal biogas production system has been built up from the average characteristics of current rural biogas plants in France. Pollutant emissions, energy demands and production are assessed for various scenarios in order to produce methane for dual fuel engines. Life cycle assessment (LCA) is used to evaluate the environmental impact of dual fuel agricultural machines, compared to diesel engines. The energy balance is always in disfavour of biogas fuel, whereas LCA energy indicators indicate a benefit for biogas production. This gap is related to the way in which the input of biomass energy is handled: in conventional biofuel LCA, this energy is not taken into account. A carbon balance is then presented to discuss the impact of biogas on climate change. Dual fuel engines were found to be interesting for their small impact. We also show, however, how the biogenic carbon assumption and the choice of allocation for the avoided methane emissions of anaerobic digestion are crucial in quantifying CO2 savings. Other environmental issues of biogas fuel were examined. Results indicate that are management and green electricity are the key points for a sustainable biogas fuel. It is concluded that biofuel environmental damage is reduced if energy needs during biofuel production are covered by the production process itself. As agricultural equipment is used during the biofuel production process, this implies that a high substitution rate should be used for this equipment. [Copyright &y& Elsevier]

Abstract: Biofuels are promoted in many parts of the world. However, concern of environmental and social problems have grown due to increased production of biofuels. Therefore, many initiatives for sustainability criteria have been announced. As a part of the European Union (EU) renewable energy promotion directive (RED), the EU has introduced greenhouse gas (GHG) emission-saving requirements for biofuels along with the first-ever mandate methodology to calculate the GHG emission reduction. As explored in this paper, the RED methodology, based on life-cycle assessment (LCA) approach, excludes many critical issues. These include indirect impacts due to competition for land, biomass and other auxiliary inputs. Also, timing issues, allocation problems, and uncertainty of individual parameters are not yet considered adequately. Moreover, the default values provided in the RED for the GHG balances of biofuels may significantly underestimate their actual impacts. We conclude that the RED methodology cannot ensure the intended GHG emission reductions of biofuels. Instead, a more comprehensive approach is required along with additional data and indicators. Even if it may be very difficult to verify the GHG emission reductions of biofuels in practice, it is necessary to consider the uncertainties more closely, in order to mitigate climate change effectively. [Copyright &y& Elsevier]

Abstract: The combined effects of climate change, the continued volatility of fuel prices, the recent food crisis and global economic turbulence have triggered a sense of urgency among policymakers, industries and development practitioners to find sustainable and viable solutions in the area of biofuels. This sense of urgency is reflected in the rapid expansion of global biofuels production and markets over the past few years. Biofuels development offers developing countries some prospect of self-reliant energy supplies at national and local levels, with potential economic, ecological, social, and security benefits. Forty-two African countries are net oil importers. This makes them particularly vulnerable to volatility in global fuel prices and dependent on foreign exchange to cover their domestic energy needs. The goal therefore is to reduce the high dependence on imported petroleum by developing domestic, renewable energy. But can this objective be achieved while leaving a minimal social and environmental footprint? A fundamental question is if biofuels can be produced with consideration of social, economic and environmental factors without setting unrealistic expectation for an evolving renewable energy industry that holds such great promise. The overall performance of different biofuels in reducing non-renewable energy use and greenhouse gas emissions varies when considering the entire lifecycle from production through to use. The net performance depends on the type of feedstock, the production process and the amount of non-renewable energy needed. This paper presents an overview of the development of biofuels in Africa, and highlights country-specific economic, environmental and social issues. It proposes a combination framework of policy incentives as a function of technology maturity, discusses practices, processes and technologies that can improve efficiency, lower energy and water demand, and further reduce the social and environmental footprint of biofuels production thereby contributing to sustainable development. [Copyright &y& Elsevier]

Abstract: For all but the last 250 years, mankind was almost entirely dependent on renewable energy, mainly from biomass and wind. Then the era of fossil fuels downed and we shifted away from renewables. But excessive use of fossil fuel has now precipitated existence-threatening climate change and ocean acidification. So the world is once again reverting to renewables in a big way. It is as if the human quest for energy has come full circle. But will this ‘home coming’ bail us out of the global environmental crisis? This paper says it will not as long as we do not drastically reduce the largely conspicuous and wasteful consumption. [Copyright &y& Elsevier]

Greater use of renewable energy is seen as a key component of any move to combat climate change, and is being aggressively promoted as such by the new U.S. administration. Yet there has been little economic analysis of renewable energy. This article surveys the literature on the economics of renewable energy and adds to it. The conclusion is that the main renewables face a major problem because of their intermittency (the wind doesn't always blow nor does the sun always shine) and that this has not been adequately factored into discussions of their potential. Without new storage technologies that can overcome this intermittency problem, much of the decarbonization of the economy will have to come from nuclear, carbon capture and storage (CCS), and energy efficiency, with geothermal and biofuels making small contributions. Nuclear and CCS are not without their problems. New energy storage technologies could greatly increase the role of renewables, but none are currently in sight. [ABSTRACT FROM PUBLISHER]

The article offers information regarding the move of European Union (EU) to launch its vision for a bioeconomy, wherein biomass will replace fossil fuels from plastics to coal plants to airplanes. It discusses the use of biomass for generating energy in EU countries, helping them to meet renewable energy and emissions targets, Other information concerning greenhouse gas emission and climate change is provided.

Biomass power is one of the most important renewable energy sources in China. In order to provide a reference for China's biomass power planning, this paper builds a power sector-planning model using the Long-range Energy Alternatives Planning System (LEAP). The results show that in the base scenario, the installed capacity of agricultural and forestry residues, municipal solid waste and biogas will increase to 22350 MW, 21150 MW, and 4900 MW, respectively by 2030. From the point of view of total volume, biomass supply is not a constraining factor for biomass power source. However, there are some social and economic factors that impede the development of the biomass power industry, some of which may not be addressed in the short term. Therefore, the development of the biomass power industry in China is a long-term process. Some policy suggestions were proposed, including reasonable planning and more subsidies for biomass supply value chain. • An optimal power-planning model focused on bio-energy in China was developed. • Agricultural and forestry power, waste power and biogas power were all analyzed. • Social and economic factors that impede biomass power were investigated. [ABSTRACT FROM AUTHOR]

The aim of the research is to present the overall and significant impact of the urban water system on the environment, i.e. environmental protection in the context of increasing the use of renewable energy sources, and how such energy sources affect climate change in general. Renewable energy sources include: wind energy, water energy, solar energy, hydrogen energy, geothermal energy, biomass energy, tidal energy, wave energy, cold energy from space and others. The application of the principles of sustainable development leads to the need to use renewable energy sources, improve their technical characteristics and functioning, and find new methods and technologies to finally abandon the use of non-renewable energy sources. To this end, it is necessary to pursue a policy based on strategic planning and the use of an integrated approach in the operation and management of urban water systems. [ABSTRACT FROM AUTHOR]

It has been established that in cold climatic zones any increase in rainfall leads to a corresponding decrease in biomass volume and in warm zones an increase in rainfall leads to an increase in biomass value. Furthermore, in water‐rich areas (900 millimeters [mm] per year), a rise in temperature causes an increase of biomass values, whereas in arid areas (300 mm per year) it causes reductions. These statements confirm previously recognized results that other researchers documented at both local and regional levels. For natural and planted tree stands, these patterns follow suit, but in absolute terms plantation biomass shows annual increases in total biomass, roots, stems, needles, and branches, of 16, 18, 11, 2, and 3%, respectively, compared to natural stands. The percentage of change in the structure of biomass is related to the ratio of the two climatic indices—temperature and rainfall. In particular, for the central part of European Russia, the Russian Far East, and northeastern China, which are characterized by mean annual temperatures in January of –10 degrees Celsius (°C) and mean annual precipitation of 500 mm, any temperature increase of 1°C at a constant level of precipitation increases biomass of stands aged 100 years in total biomass, roots, stems, needles, and branches, by 2.2, 1.8, 2.5, 0.36, and 2.3%, respectively, regardless of the origin of the stands. In the same regions and with pine stands of the same age, a precipitation increase of 100 mm at an unchanged mean temperature reduces total biomass, roots, stems, and needles by 5.8, 2.3, 6.5, and 0.3%, respectively, and increases branch biomass by 0.3%. The development of such models for the basic forest‐forming species grown in Eurasia will make it possible to predict changes in the biological productivity of the forest cover of Eurasia related to climate change. [ABSTRACT FROM AUTHOR]

Abstract: Several crops have recently been identified as potential dedicated bioenergy feedstocks for the production of power, fuels, and bioproducts. Despite being identified as early as the 1980s, no systematic work has been undertaken to characterize the spatial distribution of their long‐term production potentials in the United states. Such information is a starting point for planners and economic modelers, and there is a need for this spatial information to be developed in a consistent manner for a variety of crops, so that their production potentials can be intercompared to support crop selection decisions. As part of the Sun Grant Regional Feedstock Partnership (RFP), an approach to mapping these potential biomass resources was developed to take advantage of the informational synergy realized when bringing together coordinated field trials, close interaction with expert agronomists, and spatial modeling into a single, collaborative effort. A modeling and mapping system called PRISM‐ELM was designed to answer a basic question: How do climate and soil characteristics affect the spatial distribution and long‐term production patterns of a given crop? This empirical/mechanistic/biogeographical hybrid model employs a limiting factor approach, where productivity is determined by the most limiting of the factors addressed in submodels that simulate water balance, winter low‐temperature response, summer high‐temperature response, and soil pH, salinity, and drainage. Yield maps are developed through linear regressions relating soil and climate attributes to reported yield data. The model was parameterized and validated using grain yield data for winter wheat and maize, which served as benchmarks for parameterizing the model for upland and lowland switchgrass, CRP grasses, Miscanthus, biomass sorghum, energycane, willow, and poplar. The resulting maps served as potential production inputs to analyses comparing the viability of biomass crops under various economic scenarios. The modeling and parameterization framework can be expanded to include other biomass crops. [ABSTRACT FROM AUTHOR]

A variety of energy sources will compete to provide the energy services that humans will require over the next 100 years. The balance of these sources will depend upon the availability of fossil fuels and the development of new technologies including renewable energy technologies, and will be one of the keys in projecting greenhouse gas emissions. There is uncertainty about each of the energy sources. With oil, for example, there are two alternate views of future reserves, one that reserves are geologically limited and that supplies will declinewithin a decade or two, the other that there are enormous quantitiesof hydrocarbon in the earth`s crust and that reserves are a functionof developing technology and price. With solar voltaics, as a secondexample, there is optimism that the technology will become increasingly competitive, but there is uncertainty about the rate at which costs can come down and about ultimate cost levels. This paper reviews the reserves of fossil fuels and the prospects for nuclear power and the renewables. It also reviews the main energy conversion technologies that are available now or are expected to become increasingly available through time. However, it should be noted that, over a time horizon of 100 years, there may be quite radical changes in both production and conversion technologies that cannot be predicted and it is quite possible for some as yet unheard of technology to be developed andto transform the markets. The paper has been written to aid the development of new scenarios for the emission of greenhouse gases for theIntergovernmental Panel on Climate Change. [ABSTRACT FROM AUTHOR]

Many policies mandate renewable energy production to combat global climate change. These policies often differ significantly from first-best policy prescriptions. Among the largest renewable energy mandates enacted to date is the Renewable Fuel Standard (RFS), which mandates biofuel consumption far beyond what is feasible with current technology and infrastructure. We critically review the methods used by the Environmental Protection Agency to project near- and long-term compliance costs under the RFS, and draw lessons from the RFS experience to date that would improve the program's efficiency. The lessons are meant to inform both future RFS rulemaking and the design of future climate policies. We draw two lessons specific to the RFS. First, incorporate uncertainty into rulemaking; second, implement multi-year rules. Multi-year rulemaking allows for longer periods between major regulatory decisions and sends greater certainty to markets. We also provide two more general recommendations: tie waiver authority to compliance costs or include cost containment provisions, and fund research and development of new technologies directly rather than mandating them. Future technological advancement is uncertain, and mandating new technologies has proven to be largely ineffective to date, particularly in fuel markets. [ABSTRACT FROM AUTHOR]

The South African biofuel sector has developed slowly compared to other African contexts, despite the existence of biofuel production policy frameworks. In this article, the authors review the literature on agricultural reform and rural livelihoods in South Africa and analyse case studies from elsewhere in Africa in an attempt to draw lessons for South Africa. They argue that biofuel production does potentially threaten certain rural livelihood strategies. Interventions aimed at using land more “efficiently” risk uprooting complex livelihood strategies developed over many years to cope with colonialism, apartheid and marginalisation in general. [ABSTRACT FROM AUTHOR]

Kazakhstan is naturally rich in fossil fuels and its economy is strongly linked to oil and gas exports. Significant coal reserves have led to an energy mix that is dominated by aging and polluting thermal power plants. Yet Kazakhstan comprises mainly grassland steppe where agriculture and livestock pastoralism dominate offering the potential for cleaner, renewable energy production from a range of agricultural and forestry wastes. Here we analyse the spatial distribution and bioenergy generation potential of different feedstocks using an ArcGIS platform and demonstrate a significant opportunity for a range of bioenergy technologies. We recommend a number of policy interventions to enable Kazakhstan to make a transition to cleaner, more accessible and locally generated supply which is also sustainable and provide a waste management solution. [ABSTRACT FROM AUTHOR]

The ever-increasing energy demand has led to overexploitation of fossil fuels deposits, while renewables offer a viable alternative. Since renewable energy resources derive from phenomena related to either atmospheric or geophysical processes, unpredictability is inherent to renewable energy systems. An innovative and simple stochastic tool, the climacogram, was chosen to explore the degree of unpredictability. By applying the climacogram across the related timeseries and spatial-series it was feasible to identify the degree of unpredictability in each process through the Hurst parameter, an index that quantifies the level of uncertainty. All examined processes display a Hurst parameter larger than 0.5, indicating increased uncertainty on the long term. This implies that only through stochastic analysis may renewable energy resources be reliably manageable and cost efficient. In this context, a pilot application of a hybrid renewable energy system in the Greek island of Astypalaia is discussed, for which we show how the uncertainty (in terms of variability) of the input hydrometeorological processes alters the uncertainty of the output energy values. [ABSTRACT FROM AUTHOR]

When orchards reach the end of the productive cycle, the stumps removal becomes a mandatory operation to allow new soil preparation and to establish new cultivations. The exploitation of the removed stump biomass seems a valuable option, especially in the growing energy market of the biofuels; however, the scarce quality of the material obtained after the extraction compromises its marketability, making this product a costly waste to be disposed. In this regard, the identification of affordable strategies for the extraction and the cleaning of the material will be crucial in order to provide to plantation owners the chance to sell the biomass and offset the extraction costs. Mechanical extraction and cleaning technologies have been already tested on forest stumps, but these systems work on the singular piece and would be inefficient in the conditions of an intensive orchard, where stumps are small and numerous. The objective of this study was to test the possibility to exploit a natural stumps cleaning system through open-air storage. The tested stumps were obtained from two different vineyards, extracted with an innovative stump puller specifically designed for continuous stump removal in intensively-planted orchards. The effects of weathering were evaluated to determine the fuel quality immediately after the extraction and after a storage period of six months with respect to moisture content, ash content, and heating value. Results indicated interesting storage performance, showing also different dynamics depending on the stumps utilized. [ABSTRACT FROM AUTHOR]