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The global trend of reducing the "carbon footprint" has influenced the dynamic development of projects that use renewable energy sources, including the development of solar energy in large solar power plants. Consequently, there is an increasingly pronounced need in scientific circles to consider the impact these projects have on space and the environment. The fact that international financial institutions consider environmental effect to be a significant factor when funding solar energy projects is one of the main reasons this topic is so important in professional circles, particularly among solar energy investors. This paper highlights the fact that solar power plants can have both positive and negative impacts on space and the environment. Those impacts need to be defined in order to choose optimal spatial and territorial solutions that ensure preventive planning and active environmental protection. In the process, the application of strategic environmental assessment (SEA) in the planning and spatial organization of solar power plants becomes important. SEA is characterized by a holistic approach where complex interactions and correlations in the location of planned implementation of the solar power plant can be understood at the earliest stage of project development. By doing this, it is possible to prevent all potential risks that may emerge in the project's later stages of implementation, which is favorable both from the aspect of effective environmental protection and from the point of view of investors investing in solar power plant projects. Optimal solutions that bring about the basic role of SEA are sought primarily in the analysis of the spatial relations of the solar power plant with regard to land, biodiversity, landscape, and basic environmental factors, which is particularly highlighted in the paper. Also, the basic methodological concept applied in SEA is demonstrated, combining different methodological approaches and methods for impact assessment, as part of a unique semi-quantitative method of multi-criteria evaluation of planning solutions. [ABSTRACT FROM AUTHOR]

Driven by economic development and environmental protection, vehicles are gradually renovating their power to renewable energy. As an essential part of renewable energy, photovoltaic (PV) energy is highly valued and studied worldwide. Future social development is inseparable from it when facing the current situation of exhausting fossil energy and highly polluting. To solve the problem of the low utilization of converting solar power to electrical energy, this paper proposes a wavelet-improved fuzzy logic (W-IFL) maximum power point (MPP) control model. The W-IFL designs a wavelet network for predicting the MPP and fuzzy rules for tracking the MPP, which achieves full online control on the basis of a neural-fuzzy structure. Comparative analysis indicates that W-IFL outperforms other widely used MPP tracking (MPPT) methods, which reduces oscillation at MPP, prediction error, and tracking time, and improves training efficiency and controlling ability, thus making it more rational to promote the development of the vehicle industry. [ABSTRACT FROM AUTHOR]

People are increasingly using clean energy sources, contributing to environmental protection according to the general trend of the world. In the form of renewable energy, solar energy has contributed to solving current pressing problems, such as environmental pollution and air pollution, improving people's quality of life. The design of solar power projects in Vietnam is mainly based on meteorological data sources from Meteonorm and NASA. However, the accuracy assessment of two data sources compared to the actual solar power data in Vietnam is not available, so there is no basis to determine better meteorological data source quality to serve the design of rooftop solar power projects. The content of this paper analyzes the simulation results of a typical rooftop solar power station at the Electric Power University, Hanoi city based on meteorological data sources from Meteonorm and NASA. After that, the simulation results will be compared with the actual operating data of a rooftop solar power station near the Electric Power University and other real PV systems in the world. The study results showed that the amount of electricity production using the Meteonorm meteorological data was closer to the actual data than the NASA data source. Therefore, solar power projects in Vietnam should use Meteonorm data source for the design process to determine the best economic and technical efficiency for investors. [ABSTRACT FROM AUTHOR]

Copyright of Technical Journal / Tehnički Glasnik is the property of Polytechnic of Varazdin 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.)

In recent times, there have been notable advancements in solar energy and other renewable sources, underscoring their vital contribution to environmental conservation. Solar cells play a crucial role in converting sunlight into electricity, providing a sustainable energy alternative. Despite their significance, effectively optimizing photovoltaic system parameters remains a challenge. To tackle this issue, this study introduces a new optimization approach based on the coati optimization algorithm (COA), which integrates opposition-based learning and chaos theory. Unlike existing methods, the COA aims to maximize power output by integrating solar system parameters efficiently. This strategy represents a significant improvement over traditional algorithms, as evidenced by experimental findings demonstrating improved parameter setting accuracy and a substantial increase in the Friedman rating. As global energy demand continues to rise due to industrial expansion and population growth, the importance of sustainable energy sources becomes increasingly evident. Solar energy, characterized by its renewable nature, presents a promising solution to combat environmental pollution and lessen dependence on fossil fuels. This research emphasizes the critical role of COA-based optimization in advancing solar energy utilization and underscores the necessity for ongoing development in this field. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to provide an immediate image about the reality of the renewable energies as experienced by an Algerian company. Design/methodology/approach – The adopted approach focused on assessment of renewable energies' impact (especially the thermal solar power) on the environment and on the economic aspect of an Algerian company. Findings – The perception of environmental dimension is highlighted by means of an evaluation study supported by the calculation of quantities of CO2 emitted by two power stations (the new hybrid power station of Hassi R'mel (SPPI) and a conventional one (Sonelgaz)). Research limitations/implications – This research has limitations that the authors plan to study in perspective: assessing the impact of wind systems on the environmental and economic aspects. Practical implications – The analysis of obtained results shows and puts emphasis on the importance of renewable energies, especially thermal solar power, by identifying and evaluating the environmental and economic aspects of the new hybrid power station of Hassi R'mel (SPPI) and a conventional one (Sonelgaz) and by comparing the importance of their atmospheric emissions. Originality/value – The paper shows that this new technology represents in theory a solution for environmental problems and could also be economically competitive with conventional energies if wisely exploited. [ABSTRACT FROM AUTHOR]

With the increasing demand for electricity, more and more fossil fuels are used to generate electricity which leads to energy shortage and environmental pollution. Therefore, using Renewable Energy Sources (RESs) and developing sustainable smart grid have become a common global priority: Since RESs, like solar and wind energy, are inherently unstable, hydrogen energy, as a completely clean new energy, has received widespread attention: I-Energy, which combines information and energy, is a new research direction in smart grid. Furthermore, the household electricity usage accounts for 41% of the total power consumption. Therefore, Household Intelligent Electricity System (HIES), combining hydrogen energy and i-Energy, becomes smart solutions. In this paper, we review the scientific literature for hydrogen energy and i-Energy on HIES, including recognition of electricity appliances, establishment of power consumption model, human activity analysis, smart interactive terminal, home energy management system, distributed power supply and district coordinated power utilization. Finally, we summarize the challenges and give the solutions concerning HIES, and this work can give a useful reference to new energy used model and environment protection. • A new application of Hydrogen Energy on Household Intelligent Electricity System (HIES). • A comprehensive overview of Hydrogen Energy and I-energy on HIES. • Combining internet with traditional electricity to analyses I-energy on HIES. • Summarizing the challenges and corresponding solutions concerning HIES. [ABSTRACT FROM AUTHOR]

The damaging environmental repercussions of energy production are greatly reduced when renewable energy sources are used. Solar photovoltaic (PV) energy is reliable and secure, and it also includes benefits like no noise, no pollution, easy maintenance, and no environmental harm. Solar PV technology has emerged as the renewable energy source with the greatest rate of expansion worldwide since fossil fuels are soon running out and have a negative influence on the environment. PV modules reduce carbon dioxide emissions, preserving the environment and preventing global warming. The solar cell efficiency is one of the key elements in developing this PV technology. To increase solar cell efficiency for commercial use, the type of material used in production is essential. After serving its purpose, a PV module can be recycled, and environmentally appropriate disposal won't have much of an effect on the environment. In this article, the impact of solar PV systems and their most recent advancements for environmental preservation are discussed. [ABSTRACT FROM AUTHOR]

Currently, the need for power consumption is important to develop cities and industries. There are numerous traditional methods of receiving power for needs, but they are threats to environmental pollution. This is why we need to focus on alternative methods of receiving power. Green energy can be considered an effective means of promoting the amount of energy needed for industries, urban territories, and businesses without damaging the environment. Green energy is typically derived from renewable energy technologies such as solar, wind, geothermal, and hydroelectric electricity. The best option for improving environmental sustainability and having no negative effects on the nation's economic growth is renewable energy. Notably, one of the primaries aim of sustainable growth is to assure the availability of energy sources for future generations while spending as little money and emitting as little pollution as feasible. Green energy has, therefore, attained the aims of sustainability, i.e., they are the least costly, most effective means to increase the sustainability of a nation's productive sector, people's standard of life, and the environment. The main focus of this work is the production, utilization, and implementation of green energy sources globally. We are alone responsible for saving the planet from extinction because we are the ones who pollute it. The article primarily focuses on the advantages, necessity, and need for green technology for a brighter future. [ABSTRACT FROM AUTHOR]

The protection of the natural environment and countering global warming are crucial worldwide issues. The residential sector has a significant impact on overall energy consumption and associated greenhouse gas emissions. Therefore, it is extremely important to focus on all of the activities that can result in more energy efficient and sustainable city scale areas, preventing global warming. The highest improvement in the energy efficiency of existing buildings is possible by combining their deep refurbishment and the use of renewable energy sources (RES), where solar energy appears to be the best for application in buildings. Modernizations that provide full electrification seem to be a trend towards providing modern, energy efficient and environmentally friendly, smart buildings. Moreover, switching from an analysis at the single building level to the district scale allows us to develop more sustainable neighborhoods, following the urban energy modelling (UEM) paradigm. Then, it is possible to use the energy cluster (EC) concept, focusing on energy-, environmental- and economic-related aspects of an examined region. In this paper, an actual Polish suburban district is examined using the home-developed TEAC software. The software is briefly described and compared with other computer codes applied for UEM. In this study, the examined suburban area is modernized, assuming buildings' deep retrofitting, the application of RES and energy storage systems, as well as usage of smart metering techniques. The proposed modernizations assumed full electrification of the cluster. Moreover, the examined scenarios show potential electricity savings up to approximately 60%, as well as GHG emission reduction by 90% on average. It is demonstrated that the proposed approach is a valid method to estimate various energy- and environment-related issues of modernization for actual residential clusters. [ABSTRACT FROM AUTHOR]

Copyright of Constructii is the property of General Association of Engineers in Romania 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.)

The European Union is committed to increasing the use of renewable energies across Europe. One of the ways this is to be done is through the promotion of solar photovoltaics (PV), a method with significant environmental benefits. However, the high costs of electricity generated through PV have constrained the market reach of this option. This paper takes the form of a policy discussion, analyzing the fundamental issues concerning this type of energy, and its place in the European alternative energy market. Furthermore, a scenario is drafted to estimate how efficient solar panels should ideally be to make electricity produced by them cost-competitive with conventional, grid-tied energy sources. The study considers both a conventional scenario and another, with carbon capture costs incorporated into the final electricity prices. It is observed that in order to be competitive with conventional fossil-based electricity, photovoltaic conversion efficiencies should be around 34%. Incorporating carbon costs would further help promote solar PV, making it more price-attractive compared to emission-intensive electricity generation based on fossil fuels. The final part of the paper sheds light on the new developments on European PV, mainly in regards to the 2008 European Commission Climate Change Package, its implications and reactions from the industry. [ABSTRACT FROM AUTHOR]

Solar energy can potentially play a very important role in providing most of the heating, cooling and electricity needs of the world. With the emergence of solar photocatalytic detoxification technology, solar energy also has the potential to solve our environmental problems. However, we do not see widespread commercial use of solar energy. Some of the emerging developments in solar may change that situation. This paper describes some of the new and emerging developments, with special emphasis on: (1) nanoscale antennas for direct conversion of sunlight to electricity with potential conversion efficiencies approaching 80–90%; (2) new thermodynamic cycles for solar thermal power, that have the potential to reduce capital costs by 50%; and (3) solar photocatalytic oxidation for cleanup of industrial wastewater, drinking water, soil and air. The paper describes the fundamentals of each of these developments, their potential, present status and future opportunities for research.(1) Nanoscale antenna solar energy conversion: The current photovoltaic technologies rely on the quantum nature of light and semiconductors which are fundamentally limited by the band-gap energies. A revolutionary new approach suggested by Professor Robert Bailey in 1972 revolves around the wave nature of light. Professor Bailey suggested that broadband rectifying antennas could be used for solar to d.c. conversion. These rectennas would not have the fundamental limitation of semiconductor band-gap limiting their conversion efficiencies. Rectennas for solar conversion would have dimensions of the order of the wavelengths of solar radiation which falls mostly in the sub-micron range. The challenges in actually achieving the objectives are many. This paper describes the challenges and approaches to their solution.(2) New thermodynamic cycles for solar thermal power: It is recognized that the capital costs of solar thermal power will have to be reduced by about 50% in the near future in order to make it competitive with fossil fuels (especially natural gas) based power systems. Potential exists for meeting this goal by reducing the costs and improving the thermodynamic performance of power cycles by hybridization and combined cycle approaches and by employing new and innovative ideas in thermal power cycles. This paper describes the new thermodynamic approaches with an emphasis on an innovative new thermodynamic cycle using ammonia and water mixtures as the working fluids.(3) Solar photocatalytic detoxification and disinfection of water and air: Although the potential of solar radiation for disinfection and environmental mitigation has been known for years, only recently has this technology been scientifically recognized and researched. Solar photocatalytic oxidation has been demonstrated to effectively treat groundwater, drinking water, and industrial wastewater. In some applications such as decoloration and reduction of COD it may be the only effective method of treatment. Treatment of indoor air by the photocatalytic method has been demonstrated as the most effective technology for that application. This paper describes the recent developments and identify challenges and future research opportunities. [Copyright &y& Elsevier]

EU targets for sustainable development call for strong changes in the current energy systems as well as committed protection of environmental resources. This target conflicts if a policy is not going to promote the compatible solutions to both the issues. This is the case of the additional renewable energy sources to be exploited for increasing the share in the electricity mix and in the gross final energy consumption. Solar energy is, currently, the cheapest solution in Southern European Countries, like Italy. In this paper, thanks to the availability of three open databases provided by National Institutions, the authors compared the historic trends and policy scenarios for soil consumption, electricity consumption, and renewable electricity production to check correlations. The provincial scale was chosen as resolution of the analysis. The deviations from the policy scenarios was then addressed to identify the demand for policy recommendations and pathways to promote in order to achieve the target for renewable electricity share as well as the reduction in soli consumption trend in 2030. The role of renewables integrated in the existing contexts, such as building integrated photovoltaics, is considered a key driver for solving this issue. [ABSTRACT FROM AUTHOR]

The current editorial summarized some of the scientific works presented in the Sustainable Energy and Environmental Protection (SEEP) conference-held at the University of the West of Scotland, UK, 2018. The selected work was directly related to the scope of the Renewable, Sustainable Energy Reviews (RSER) journal. During the conference activities, experts from all around the world in the subjects of: renewable energy, climate change, optimization, and economics presented and discussed the progress made in renewable energy sources, as well as the new strategies for protecting the environment from the hazards connected with fossil fuel utilization. The methods presented in the conference focused on several directions: the development of efficient energy conversion systems with low/no environmental impacts; the suggested policies to widespread renewable energies; the restriction in the emission of greenhouse gases, and the recent progresses in CO 2 capture. This editorial focused on the renewable energy developments and their positive effect on the climate change, and briefly summarized the accepted manuscripts in this issue. • Effects of renewable energy on climate change. • Background on the International Conference on Sustainable Energy and Environmental Protection SEEP. • Summary of selected papers of SEEP 2018. [ABSTRACT FROM AUTHOR]

Due to the issue of environmental protection coupled with high energy demand, there was an initiation for exploration of different renewable energy sources. This article aims to optimize the total annual cost of hybrids of wind and solar renewable energy system to satisfy the predesigned load. Minimization of the total annual cost of the system by determining appropriate numbers of the components, so that the desired load can be economically and reliably satisfied under the given constraints. Gravitational Search Algorithm (GSA) was employed for the optimization process. GSA is a recently proposed metaheuristic algorithm which is based on Newton's universal gravitational law of gravity and mass interactions. It uses stochastic rules to escape local optima and find the global optimal solutions. MATLAB codes were designed for the developed fitness function and employed algorithm. The proposed methodology was run for the fitness function through the code and the results were discussed. The result was compared with the results of Particle Swarm Optimization (PSO) and also shown that: GSA has some advantage over PSO algorithm. Even though, the algorithm has several parameters to be adjusted, it is strong in both local and global optimal searches. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Polonorum. Oeconomia is the property of Wydawnictwo SGGW 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 paper proposed an experimental test: the solar water-heating system was been monitored for a whole year to analyze collector performance in an actual operation process. Heat-collecting efficiency, heating capacity, power consumption, and heat required were analyzed theoretically. Results showed that solar irradiance and ambient temperature were positively correlated with heat collection efficiency, and the daily average heat collection efficiency was up to 56.63%. In winter, the auxiliary heat source consumed the most power, almost all of which bears the heat of users. The heat collection in summer met the demand for hot water, and the guarantee rate of solar energy could reach 100%. The energy saving properties and CO2 emission reduction were analyzed. This system had a significant effect on the energy-saving effect and environmental protection. The analysis showed that the hot-water system can fully meet the design requirements under the condition of relatively sufficient solar energy, and can operate stably, which has a certain guiding significance for the design and application of large-scale solar hot-water systems. [ABSTRACT FROM AUTHOR]

The aim of the research was to study the environmental concern among sheep farmers in Bulgaria. Questionnaire information was collected from 22 sheep farmers in Bulgaria about their attitude toward environmental protection. It was found that more than half (66.7%) of farmers tried to purchase on a regular base equipment or raw materials that pollute the environment less. 61.9% of the respondents considered environmental protection to be very high priority for the farm. None of the farmers stated that environmental protection was very low priority for the farm. The surveyed Bulgarian sheep farmers were in general interested in environmental protection, they strove to purchase equipment and raw materials that were safe for the environment, but this wasn’t always possible for them mainly due to lack of funds and insufficient awareness of environmental issues. We also concluded that the better competitiveness of the farm led to higher willingness for investing in environment friendly materials and equipment (p < 0.05). There was a tendency for an increase of the environmental concern with the increase of the competitiveness of farms. One of the methods for farmers to protect the environment was by usage of pesticides that did not affect bees and aquatic organisms, and packaging collection. Biggest part of manure and animal bedding were utilized as soil fertilizers. About a third of crop leftovers was used to feed sheep. Another part was used as bedding material. Only 13.6% of farmers used renewable resources and energy: solar photovoltaic and collecting rainwater in micro-dams. 45.5% of the farms had their own water source: water pump and / or micro-dam. A small part of the farmers (13.6%) had certified organic production: they produced organic meat, milk, and fodder. [ABSTRACT FROM AUTHOR]

A global goal is to call for common solutions to the challenge of environmental conservation. The cheap, clean and green energy and processes help to beat the hazardous pollution of plastics. An action of the STEP (Solar Thermal Electrochemical Process) on the polymer is to create a novel vision of the depolymerization of plastics to generate valuable fuels plus abundant hydrogen. In this paper, a solar thermo-coupled electrochemical system was first designed and employed to realize the plastics depolymerization to useful fuels for enhanced the solar utilization and the chemical polymer conversion. Exemplified by polypropylene (PP), the plastics were efficiently converted to light fuel and hydrogen via the solar-driven electrolysis coupled with pyrolysis. The results demonstrated that the depolymerization temperature was greatly lowered compared to conventional pyrolysis. The STEP conversion rates increased with a lift of the temperature and current. The high total conversion rate was significantly achieved by reaching 68.48% at 350 °C, including the solid phase of 31.52%, the liquid phase of 7.85% and the gas phase of 60.63% (w/w), which was compared to the 28.39% of the sole pyrolysis. The hydrogen was evolved during the process in the final volume of 72.5 ml, which was about 9.3 times more than that of the pyrolysis at 400 °C. In the outdoor experiments, the total conversion reached 66.64% at 350 °C, which was compared to 26.37% of the pyrolysis only. The light hydrocarbons were richly produced in the distribution of C 1 –C 5 hydrocarbons while only tiny amounts of methane and ethane were probed in the pyrolysis. The common mechanism and pathways can be tentatively proposed in a mode of the radically initiated thermochemical reactions and electrochemical redox by the induction of the solar thermo-coupled electrolysis. • The STEP plastics depolymerization was firstly created and studied. • The depolymerization was driven by the solar thermochemical-coupled electrochemical processes. • The STEP plastics depolymerization largely reduced the reaction temperature. • The STEP conversion rates were more significantly improved compared to the one of the pyrolysis. • The STEP depolymerization efficiently yields abundant hydrogen and light hydrocarbons. [ABSTRACT FROM AUTHOR]

The aim of the manuscript was to present the collective results of research on the profitability of using various renewable sources in Poland with the greatest development potential. In the paper, the economic parameters of various investment projects were determined and calculated, i.e., Net Capital Value (NPV), Internal Rate of Return (IRR) and the Period of Return on Invested Capital (PBT). The economic assessment of the use of RES technologies was supplemented with the assessment of environmental benefits. The ecological criterion adopted in the study was the assessment of the potential and costs of reducing greenhouse gas emissions as a result of replacing fossil fuels with renewable energy technologies. On the basis of the constructed economic model to assess the profitability of investments, it has been shown that the analyzed projects will start to bring, depending on their type and technical specification, measurable economic benefits in the form of a reduction in the amount of energy purchased on an annual basis and environmental benefits in the form of reduction of carbon dioxide emissions to the atmosphere. Moreover, the calculations show a high potential for the use of certain renewable sources in Poland, which contributes to the fulfillment of energy and emission obligations towards the EU. The analyzes and research of the Polish energy market with the use of the presented models have shown that the project is fully economically justified and will allow investors to make a rational decision on the appropriate selection of a specific renewable energy source for their investment. The presented economic models to assess the profitability of investments in renewable energy sources can be successfully used in other countries and can also be a starting point for a discussion about the direction of energy development. Due to the lack of collective, original and up-to-date research on the domestic market, the manuscript provides the reader with the necessary knowledge regarding the legitimacy of using renewable energy sources, investment and environmental profitability.

Solar energy policy has become controversial in Virginia and many other states. Proponents point to its environmental, public health, and economic development benefits, and argue that it can help support electric grid operations. However, detractors, including many electric utilities, contend that the growth of customer-owned, distributed solar energy systems will create costs that must be passed on to ratepayers. This article presents a case study in which the authors led a multi-faceted Solar Stakeholder Group to evaluate the costs and benefits of distributed solar energy in Virginia. We examine this project in the context of collaborative planning theory, finding that it created shared learning among participants and facilitated greater understanding of opposing viewpoints, but did not produce a consensus vision for future action. We also note some of the Stakeholder Group's broader contributions to the 'value-of-solar' debate and discuss its implications for future distributed solar energy efforts in Virginia. [ABSTRACT FROM AUTHOR]

Global warming and climate change are the most serious problems for developing countries as well as the world. Therefore, the usage of renewable energy sources is gaining importance for sustainable energy development and environmental protection. Turkey is one of the developing countries whose demand of electricity is sharply increasing. In order to meet this demand by means of renewable sources, solar power is a suitable source due to the high solar energy potential of Turkey among the renewable sources. In this article, the multi-criteria axiomatic design (AD) approach is proposed for the evaluation of sites for a grid-connected photovoltaic power plant (GCPP) in Turkey. For this aim, four evaluation criteria, which have great influence on determination of a GCPP site are taken into account. [ABSTRACT FROM AUTHOR]

Projections are important tools for long-term planning and policy settings. Renewable energy sources that use indigenous resources have the potential to provide energy services with zero or almost zero emissions of both air pollutants and greenhouse gases. Currently, renewable energy sources supply 14% of the total world energy demand. Renewable energy is a promising alternative solution because it is clean and environmentally safe. Approximately half of the global energy supply will be from renewables in 2040. Photovoltaic systems and wind energy will be able to play an important role in the energy scenarios of the future. The most significant developments in renewable energy production are observed in photovoltaics (from 0.2 to 784 Mtoe) and wind energy (from 4.7 to 688 Mtoe) between 2001 and 2040. Biomass is the most used renewable energy source now and in the future. The potential of sustainable large hydro is quite limited to some regions in the world. The potential for small hydro (< 10 MW) power is still significant and more significant in future. Photovoltaic systems and wind energy are technologies with annual growth rates of more than 30% during the last years that will become more significant in the future. Geothermal and solar thermal sources are more important energy sources for the future. Photovoltaics will then be the largest renewable electricity source with a production of 25.1% of global power generation in 2040. [ABSTRACT FROM AUTHOR]

The current worldwide energy consumption is largely dominated by non-renewable energies such as coal, oil and gas. For well-known reasons, this concept should be changed to a more sustainable one based on renewables. As learned from history, a transition from one energy system to another has always taken about 100 years. A dynamic material flow model is developed to simulate some key elements for the implementation of renewable energy systems on a large scale. These key elements are the required industrial capacity, the energy and financial requirements and the impact on greenhouse gas mitigation. Results are presented for wind, photovoltaic, hydro, solar thermal, geothermal and biomass electrical energy systems. The comparison of two different implementation strategies, moderate ≈60 years and fast ≈30 years, shows that the implementation time is the only limitation, resulting in large production overcapacities. The energy and financial needs are not as critical. The implementation of renewables on a large scale would considerably reduce CO2 emissions by 2 tons per person per year for a world population of 7 billion people. [ABSTRACT FROM AUTHOR]

A 450-ppm equivalent CO2 target by 2050 is an often-proposed goal under a future global emissions agreement, but there is considerable high side risk in global-warming models due to cloud formation, feedbacks in dissolved organic carbon from peat bogs in polar regions, and unaccounted solar dimming by particulates. The 450-ppm figure is predicated on absorption of some CO2 by oceans, but increasing acidification may dictate that CO2 produced during the next 50 years may have to be reduced further to preserve species diversity in the oceans. By consideration of industry capability, a 400-ppm target is shown to be affordable and achievable by renewables using 2/3 direct solar electricity by 2050 with technology currently being proven, together with aggressive energy efficiency. Sequestration of liquid CO2 under pressure in enormous continually excavated caverns at 2-km depth is technically much less certain and later in development. [ABSTRACT FROM AUTHOR]

The article deals with thermal pollution as a descriptive term for unwanted heat energy accumulating in any phase of the environment in the U.S. Accordingly, some of the important problems faced by people are ecological problems arising from the unrestrained growth of the human population and the resultant increasing strains being placed on the earth's life support system. Thus, the physical labor performed by man and the work done by domestic animals are also means of utilizing the solar energy that keeps the atmosphere and hydrosphere in motion. There are available resources of energy that man can use without raising the average temperature of the earth, but the use of fossil fuels or nuclear or thermonuclear reactions will raise the temperature.