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Recently, solid desiccant air conditioning system has been proposed as an alternative to the conventional vapor compression refrigeration air conditioning systems for efficient control over humidity of conditioned air especially in hot and humid areas. The solid desiccant cooling can be more favorable over the traditional vapor compression refrigeration air conditioners, because it assures more accessible, economical and cleaner air conditioning. It is still more important when it is powered by free energy sources like solar energy and waste heat with temperatures of between 60°C and 80°C. In addition, it can significantly reduce the operating cost as well as save energy. In the present paper, principle of solid desiccant cooling system is recalled and its technological applications and advancements are discussed. Through a rigorous literature review, different configurations of desiccant cooling cycles, conventional and hybrid desiccant cooling cycles, different types of mathematical models of rotary desiccant dehumidifier, performance evaluation of desiccant cooling system, technological improvement and the advantage it can offer in terms of energy and cost savings are highlighted. This paper also gives a detailed account of the general features and performance of the solid desiccant cooling system when it is powered by solar energy or industrial waste heat for regenerating the desiccant. This review is useful for making opportunities to further research of solid desiccant cooling system and its feasibility which is becoming common in the coming days. [ABSTRACT FROM AUTHOR]

Electricity supply in remote areas of the Russian territory is heavily dependent on diesel sources. Diesel generation imposes an important economic and social burden on the local population, besides the environmental impact of greenhouse gas emissions, black carbon and oil spills. Switching to renewable energy could reduce the current economic, social and environmental cost of electricity supply in Russia׳s remote areas. The objective of this paper is to review Russia׳s off-grid renewable energy policy by focusing on the promotion of wind- and solar-diesel hybrid energy in the Russian Arctic. Taking a mainly regulatory perspective, this paper identifies existing barriers to the development of hybrid renewable-diesel investments. Building further on the international experience with the promotion of renewable energy in Arctic climates ( e.g., in Alaska and Canada), this paper tests the feasibility of alternative ‘best practice’ mechanisms to support off-grid renewable energy in Russia. [ABSTRACT FROM AUTHOR]

Several theoretical studies have been reported in recent years which have indicated that large-scale wind farms can have an impact on local and regional meteorology, possibly on climate. Now evidence of it based on field observations has also begun to emerge. The present paper traces the evolution of this knowledge. It discusses the theoretical studies on the possibility of wind turbines effecting climate change, and summarizes the emerging confirmation of those predictions. The concluding part of the paper assesses the implications of these findings in the context of the world׳s past experience on global warming and its present thrust to meet substantial portions of its energy needs with renewables. [ABSTRACT FROM AUTHOR]

Life on Earth originated and survived millions of years as a result of the favorable climatic conditions. The climate can be considered as a renewable resource whose energy component is comprised from the solar energy, while the material component represents oceans as water tanks. Renewable energy sources (RES) can be divided into two main categories: traditional renewable energy sources such as biomass and large hydropower plants and the so called “new renewable energy sources” such as the solar energy, wind energy, geothermal energy, etc. This paper refers to the potential and utilization of RES in the southeastern planning region in the Republic of Macedonia. The main goal of the paper is to analyze possibilities of using the RES which naturally belong to the areas of the ten municipalities located in this part of the Republic of Macedonia. This is achieved by defining the existing potentials of RES in the region, the state of their current usage, balance and categorization based on quality, energy value, energy resources, etc. Methodology used in the research is also presented in the paper. [ABSTRACT FROM AUTHOR]

The demand for electricity is increasing day by day, which cannot be fulfilled by non-renewable energy sources alone. Renewable energy sources such as solar and wind are omnipresent and environmental friendly. The renewable emulnergy sources are emerging options to fulfill the energy demand, but unreliable due to the stochastic nature of their occurrence. Hybrid renewable energy system (HRES) combines two or more renewable energy sources like wind turbine and solar system. The objective of this paper is to present a comprehensive review of various aspects of HRES. This paper discusses prefeasibility analysis, optimum sizing, modeling, control aspects and reliability issues. The application of evolutionary technique and game theory in hybrid renewable energy is also presented in this paper. [ABSTRACT FROM AUTHOR]

This paper reviews solar-selective coatings for concentrating solar power (CSP) applications. CSP systems require direct sunlight and solar tracking and utilize solar absorbers to convert sunlight to thermal electric power. Because this system receives direct sunlight which operating temperatures higher than 600 °C, heat-resistance new materials are needed to cope with. This paper presents a simple and low-cost process for depositing the high-temperature solar absorber. The high selective absorbing Fe 2 O 3 films deposited on stainless steel (SS304) substrates to be absorbers by high thermal process at 850–1050 °C. The crystalline structure, surface microstructure and optic properties of the films were determined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV/visible spectroscopy (UV–vis–NIR Spectrophotometer, 0.25–2.5 μm). Optimal Fe 2 O 3 films on SS304 substrates at (900–1000 °C) displayed high absorptivity ( α ) (0.909–0.922) and their emittance values( ε ) are relatively low (0.18–0.38). This study proved the possibility of preparing high-temperature solar selective absorbing coatings with high solar absorptance and low emittance by using a simple thermal oxidation process. Those films have very good prospects for solar absorber because of simple process, low-cost, large-area and good performance. [ABSTRACT FROM AUTHOR]

The air conditioning market has witnessed a significant development in liquid desiccant air conditioning (LDAC) technologies over the past few decades. Many previous studies have confirmed that technical and economical deficits associated with conventional air conditioning systems can be eliminated using LDAC technologies. As a result, LDAC technologies – both equipment and systems – have become hot topics for research, which has resulted in hundreds of research papers in the scientific literature. The objective of this paper is to present a comprehensive overview of LDAC equipment and systems, and to identify gaps in the literature to be considered by future research. [ABSTRACT FROM AUTHOR]

Upon the basic idea of the updraft solar heating, the solar chimney was proposed and implemented as a model and a prototype by many research and industrial bodies. Although the system efficiency is below 2%, but it is a promising technology to harness and convert the solar energy to electric power through three basic components; namely: solar collector, tower or chimney, and wind turbine-generator unit. The low efficiency, the bulk size and the high dependency on the solar irradiation are the major issues experienced in the solar chimney power plants. Since the implementation of the first prototype in Manzenares, numerous attempts have been reported to enhance the performance of the system. The present paper is compiling most of the reported attempts to enhance the performance of the solar chimney power plant. The conclusion drawn is that the system performance can be enhanced considerably via integration with another source of thermal energy, or by using efficient solar thermal energy storages. This paper provides a platform to the researchers in the field to understand and get detailed literature on the enhancing technologies of the solar chimney power plant current updates. [ABSTRACT FROM AUTHOR]

According to UNDP Policy Note 2014, only 23% of Yemen rural community have access to electricity – having connected to national grid or use small isolated generating units – while the country is one of the richest in solar energy with over 3000 h per year clean blue sky. The objectives of this paper is to concentrate on the utilization and the cost effectiveness of photovoltaic solar energy for electrification of Yemeni rural and desert communities, which will result in enhancing education, culture, science, medical services, and improve the living conditions in rural areas. Otherwise, energy poverty that is a facet of a multidimensional poverty in Yemen will persists because the possibility of connecting rural communities to the national grid, even in the next ten years, is invisible due to major political and financial problems that the country is facing. Moreover, PV energy is environmentally clean and has proved to be one of the best solutions for rural electrification in many countries worldwide due to noticeable drop of PV systems prices with the advance in PV technology. Accordingly, it should be the best solution for rural electrification in Yemeni as well. The paper demonstrates the cost effectiveness and the design procedure of utilization of solar energy for rural and desert communities in Yemen using a number of subsequent cases typical to Yemeni communities and provides also a practical study to support Bedouin backpackers. [ABSTRACT FROM AUTHOR]

Given that the first industrial revolution was based on Steam Engine (coal as energy source), and the second on oil and electricity, where both these revolutions are actually "high carbon" revolutions, it is logical to expect that the third industrial revolution should be based on systems of renewable energy sources (RES), in order to minimize the problems arising from climate changes and to achieve sustainable development. However, the usage of the RES technologies and daily/weekly storage of energy and their connection to smart grids is not enough for the expected third industrial revolution. The start of this revolution would require technologies that have a great potential for further development and ability to supply, at any time, the necessary energy and power to a settlement/city, as well as drinking water, meeting the peak load requirements, continuously throughout the year, and independently of external sources of energy and drinking water. This would be provided from intermittent RES energy (solar, wind, etc.) and sea or other unclean source of water as natural resources. In that context, this paper presents a radically new technological solution: Key Engine which uses only natural resources: the sun, sea and gravity, in order to continuously and simultaneously supply a consumer with energy, power and drinking water. This solution has all the essential features required to start a third industrial revolution. The basic unit of Key Engine consists of the solar thermal (ST) generator with parabolic trough collectors through which sea water flows directly, absorbing thermal energy of solar radiation. After the separation of steam from seawater, the steam drives turbines and generators and produces electricity that is delivered to Pump Storage Hydroelectric (PSH) facility with seawater, which balances the daily and seasonal surpluses and shortages of energy, thus ensuring a continuous supply of electric power and energy to a consumer. At the same time, the water that comes out of the turbine, passes through the water treatment unit and is stored in drinking water reservoir, enabling continuous supply of the same consumer with drinking water. The paper presents theoretical aspects of Key Engine, model for optimal sizing and practical formulas for the calculation of characteristic values of the system, which could be the basis for further scientific research, development and innovative solutions that would help engineers in practice for numerous and diverse applications of Key Engine. In order to verify the derived mathematical relationships and models for optimizing the Key Engine in real conditions, the case study of the island of Vis in the Adriatic Sea, Croatia, has been considered, along with total annual irradiance of 1575 kW h/m 2 a, total annual electric energy consumption of 20 GW h and drinking water consumption of 453,382 m 3 . The obtained results: power of ST generator of 52 MW, working volume of the upper reservoir of 7 hm 3 , total annual electric energy production of 62 GW h/a, and drinking water production of 480,754 m 3 /a, clearly show that the new technology can fully meet the needs of the considered consumer for energy and drinking water. As the basic idea of Key Engine relies on the use of natural resources, i.e. RES energy and sea, the paper presents only the starting solution, whereby, apart from the sun, RES can be wind, or other renewable sources, that can perform separation of vapor from seawater and thus produce drinking water, as well as energy simultanously. Also, energy storage may not be performed solely by the PSH technology, but also by any other technology that can provide seasonal balancing of energy. All this suggests that the Key Engine can be understood as an open-source for RES technology development and thus bring changes in all three aspects of sustainable development: economy, society and environment. [ABSTRACT FROM AUTHOR]

Access to environmentally clean and renewable energy is critically linked with sustainable and inclusive development leading to improvement in overall standard of living of people in rural areas. Availability of such energy in remote areas can foster economic activities and create various avenues for livelihood, whereas lack of sufficient and secure energy may constrain economic growth and development. Given that solar electrification has been gaining increasing importance as a source of environmentally clean and economically efficient energy for people living in rural areas, the present paper is an attempt to understand its socio-economic and environmental implications. Analyzing experiences from two villages of the Indian state of Odisha, the paper finds that households’ adaptation to solar energy depends on a set of socio-economic, demographic and institutional factors including governments’ approach towards rural electrification. It is also found that solar home system has facilitated socio-economic activities and improved standard of living of households, especially of women living in the area. The beneficiary households also perceive that solar electrification has improved environmental standard by reducing household pollution resulting from use of traditional sources of energy such as kerosene, though confirmation in this regard requires further investigation. However, households’ adaptation to solar energy and realization of its potential benefits seems to be constrained by non-availability of maintenance and repairing facilities and access to conventional grid electricity under various programmes of the government. In addition to scaling up solar technology, an institutional framework with quality leadership and active participation of NGOs and other community level organization is necessary to link markets and policies effectively and enhance households’ inclination towards greater use of this energy. [ABSTRACT FROM AUTHOR]

Solar energy is one among the freely available clean forms of renewable energy. Many technologies have been developed in India for extracting energy from assorted renewable energies, but the maximum extraction of thermal energy from solar energy is the most promising challenge. This paper focuses on the performance and efficiency of solar parabolic trough collector. It also reviews the pertinent applications of solar energy such as air heating system, desalination, refrigeration, industrial heating purposes and power plants. This paper will be useful for researchers concentrating on solar energy using parabolic trough collector. [ABSTRACT FROM AUTHOR]

Energy is the largest overhead cost in the production of agricultural greenhouse crops in temperate climates. Moreover, the initial cost of fossil fuels and traditional energy are dramatically increasing. The negative environmental impacts, limited sources of fossil fuels and a high consumption of energy and food have caused the increase in demand for solar energy as a green and sustainable choice. Therefore, this paper reviews the solar energy application technologies in the environmental control systems of greenhouses (cooling, heating and lighting) mainly the generated energy of photovoltaic (PV) and solar collectors, as well as the PV water pumping for irrigation. Furthermore, this paper briefly discusses the economic analyses and the challenges for this technology. [ABSTRACT FROM AUTHOR]

Low cost, two axis tracking solar dish with flat mirror system׳s (Solarux CSP) design and its advantages are described in this paper. System is based on the Concentrating Solar Power (CSP) technology. Heat energy and electricity are produced using oil and sunlight. In design stage, cost of production, constructability, automation, safety, cleaning and required energy that is required for the system have been taken into account. In this paper, it has been focusing on air-conditioning, heating, and producing electricity by using Solarux CSP. The aim of this invention is to use planar mirrors instead of parabolic mirrors in order to recuce cost and design a system that can be manufactured easily, can be constructed on every kind of terrain (rocky, plain etc.) and can be used by third world countries. For this purpose, for the development and design of solar flat system Solid Works 2012 has been used and the results are discussed and shown briefly. [ABSTRACT FROM AUTHOR]

Unfilled gap of prolonged energy demand by conventional energy sources and consent of global warming as its vulnerable outcome provides a vent to search compatible option. Augmentation in use of solar energy reveled through last 3 decades portrays its heterogeneous rewards in the prevailing energy scenario. Nevertheless solar PV system arises as viable option in the critical power system era its low efficiency energy conversion attribute necessitates an efficient power conversion system. The nonlinearity of I – V (current–voltage) characteristic and its alteration for an assorted insolation and temperature values may enable the alteration in terminal voltage. This may deviates maximum power point due to which the available maximum power delivery to load can be differed. Literature of this field reiterated that the uniform insolation and partial shading condition demands undeniable need of maximum power point tracking. Nonetheless through investigation in this direction furnishes the availability of a bunch of such techniques; each of them posses its own pros and cones. This ubiquitous trait of available maximum power point tracking (MPPT) techniques unfolds the complexity in its precise selection. To diminish such complexity this paper offers a state of art of various MPPT technique and their comprehensive comparative analysis based on 110 standard research articles. The focus of this paper is to offer a better commencement and to furnish valued information for investigators of this field. [ABSTRACT FROM AUTHOR]

Adsorption refrigeration technology has established enhanced significance in last three decades, due to its noiseless, non-corrosive and environment friendly operation by the utilization of low grade heat sources, especially solar energy. A plethora of adsorption cooling systems had been developed but still these cooling systems are not ready to compete with the traditional vapor compression cooling systems. This paper aims to provide fundamental knowledge on the adsorption systems and presents a comprehensive literature review of the past efforts in the field of their solar energy utilization. This paper also presents a brief of various related researches conducted in India. A survey of developments in the market trends is also presented in this paper. It shows that a number of attempts have been made by various companies to enhance the performance of adsorption refrigeration systems and maintain their presence in market but limitations regarding their technical and economic aspects seem difficult to overcome. Nevertheless, adsorption cooling systems driven by solar energy not only lowers down the daily electricity consumption but also reduces the global warming potential due to its environment friendly nature. [ABSTRACT FROM AUTHOR]

The solar energy generation has grown significantly in the past years. The importance of PV penetration in power system as a major element of renewable energy source has seen it being widely used on a global scale. Despite its promising success, PV penetration presents various issues and its impact on the distribution system has to address for seamless integration in the power system. In this paper, a comprehensive overview on important issues affecting the distribution system as a result of PV penetration is presented. Pertinent issues such as voltage fluctuation, voltage rise, voltage balance, and harmonics and their effect on the system are discussed in details. The islanding issues, which are of critical importance to the stability and integrity of the system, are also thoroughly reviewed. Details on different islanding techniques – remote and local techniques and their advantage and disadvantages are shown. Therefore, this paper can provide useful information and serve as a reference for researchers and utility engineers on issues to be considered with regards to PV penetration. [ABSTRACT FROM AUTHOR]

The use of the two-phase closed thermosyphons (TPCTs) is increasing for many heat transfer applications. This paper reviews the most recent published experimental and theoretical studies on the TPCT. After a description of the TPCT operating principle and the performance characteristics, the heat transfer analysis in condenser and evaporator sections that depends on the complex two-phase process are described. The influence of the affecting parameters on the performance of TPCTs such as the geometry (diameter, shape and length), the inclination angle, the filling ratio (FR), the working fluid, the operating temperature and pressure analyzed by various researchers is discussed. The various operating limits occurring in a thermosyphon includes viscous, sonic, dryout, boiling and flooding are also analyzed. Considering the application of TPCTs, the paper presents a review of experimental tests and applications. This paper can be used as the starting point for the researcher interested in the TPCTs and their renewable energy applications. [ABSTRACT FROM AUTHOR]

The term “polygeneration” is referred to as “an energy supply system, which delivers more than one form of energy to the final user”, for example: electricity, heating/cooling, desalination can be delivered from polygeneration process. The polygeneration demonstrates unique integration of energy efficiency and renewable energy. It is the next generation energy production technique with a potential to overcome intermittence of renewable energy, reduce cost of power generation and greenhouse gas emissions. The feasibility study of this paper is divided in three sections: In first section of this study, solar and biomass have been arranged to produce steam for power generation. In the second section, cooling is produced by vapor absorption refrigeration (VAR; LiBr-H 2 O) system as per demand load requirement using steam, extracted from pass-out turbine. In the last section of this paper, multi effect dehumidification (MED) water desalination is produced by using limited amount of heat from water vapor (refrigerant; H 2 O) through HE1 of VAR cooling system. [ABSTRACT FROM AUTHOR]

Balancing power is used to quickly restore the supply-demand balance in power systems. The need for this tends to be increased by the use of variable renewable energy sources (VRE) such as wind and solar power. This paper reviews three channels through which VRE and balancing systems interact: the impact of VRE forecast errors on balancing reserve requirements; the supply of balancing services by VRE generators; and the incentives to improve forecasting provided by imbalance charges. The paper reviews the literature, provides stylized facts from German market data, and suggests policy options. Surprisingly, while German wind and solar capacity has tripled since 2008, balancing reserves have been reduced by 15%, and costs by 50%. [ABSTRACT FROM AUTHOR]

The rapid depletion of energy resources, increasing energy demand and degeneration of ecological values need an urgent solution in this age. Solar energy as the most important energy resource has become part of the solution to the world’s energy challenges. Solar radiation data that provides the information on how much energy strikes to the earth is needed for utilization, planning and designing of solar power plants. The measurement of solar radiation data is generally available in some specific areas due to difficulty in solar radiation measurements in terms of its initial and maintenance costs. Therefore, solar energy modelling techniques are becoming more and more important due to the increasing need for the design, performance evaluation and improvement of the solar energy applications. The primary aim of this paper is to overview solar radiation modelling techniques to identify optimum models available and to classify research fields in the literature. In this paper, the modelling techniques, data information, accuracy tests of models used in around 90 papers were reviewed and the most accurate models were suggested. [ABSTRACT FROM AUTHOR]

Solar still is an ideal source of fresh water for both domestic and agricultural aspects. It is one of the most important viable applications of solar energy. The simplest and most proven type of solar stills is the single basin type, but its thermal performance is limited. Many research papers were presented where different methods were performed to improve the productivity of single basin solar stills. In this paper, a review of different designs of solar stills was presented particularly the double, triple and multi-effect solar stills, vertical stills, tubular type solar stills, finned and corrugated stills, and stepped type solar stills. A detailed cost analysis for different configurations was presented. The various parameters affecting the performance of the considered designs of solar stills were outlined. The daily productivity of the double basin solar still is on the average 36% higher than that of the single basin still. The inverted absorber triple basin solar still gives a substantially higher yield than double and single basin inverted absorber solar stills. An optimum area of the vertical still absorber was found to be 3.5 m 2 . From the results obtained for the tubular solar still it was concluded that with cooling air flow, the production increased by about 32.8%, and with cooling water flow, it further increased by about 59% more than the system without cooling. A maximum increase in productivity of about 98% was achieved for stepped solar stills when fins, sponge and pebbles were used. The maximum productivity of stepped solar still was obtained with tray depth and width of 5 and 120 mm, which is about 57.3% higher than that of the conventional still. [ABSTRACT FROM AUTHOR]

The present global energy scenario, in which fossil fuels play a preponderant role, faces significant energy and environmental challenges. To help address these challenges, countries across the world are increasing the contribution made by renewable energy (RE) resources to their energy supplies. Feed-in Tariff (FiT) is one of the most effective incentive policies used to promote the RE sector especially at the micro-generation level. The key objective of the FiT schemes is to provide financial support to residential, industrial and commercial consumers to encourage them to become RE producers. Solar photovoltaic (PV) is one of the most promising RE technologies. This paper provides an overview of the solar PV developments in the Association of South East Asian Nation (ASEAN) countries. It reflects upon the RE trends in the world as well as providing an introduction to the ASEAN countries. It reviews the progress of solar PV in each of the ASEAN countries especially in terms of RE policies, growth in terms of PV installations and research and development activities. Finally, the paper presents conclusions and a set of recommendations. Out of the 10 ASEAN countries, 5 have implemented FiT as a key policy incentive to stimulate the progress of RE. It is found that the ASEAN countries have great potential for solar PV in term of their annual solar insolation levels, which ranging from 1460 to 1892 kWh/m 2 per year. [ABSTRACT FROM AUTHOR]

The use of photovoltaic power plants is rapidly expanding, despite the continued growth in the production of traditional mineral resources. This paper analyses photovoltaic panels (PVP) in order to identify the best values of their various nominal (rated) parameters in terms of lifetime and efficiency. The authors have created a database of one-sided PVPs from 100 to 450 W power range, which includes PVPs from 72 manufacturing companies around the world. The paper analyzes 1300 mono- and polycrystalline, heterostructural and thin-film PVPs. The following PVP parameters were analyzed: efficiency, temperature coefficients of power, short circuit current, open circuit voltage, square per power, mass per power, number of cells, operating temperature and lifetime. The results obtained can be widely applied in simulating the operating modes of photovoltaic power plants and will improve the accuracy of feasibility studies of the implementation of autonomous power supply systems. • Parameters of photovoltaic panels (PVPs) is necessary for modeling and analysis of solar power systems. • The best and the median values of the main 16 parameters among 1300 PVPs were identified. • The results obtained help to quickly and visually assess a given PVP (including a new one) in relation to the existing ones. • The median and the best parameters will reduce the time of feasibility studies for the implementation of autonomous photovoltaic power plants. • According to the medians of parameters, the most efficient are heterostructural PVPs, the least efficient are thin-film PVPs. [ABSTRACT FROM AUTHOR]

Solar PV has been a cornerstone for the energy policy makers around the globe. It is because the environmental effects of solar energy are low as compared to the conventional energy sources. It is free and virtually inexhaustible. Developed countries have long been in the business of using solar energy for energy generation. However, for the third world countries like Pakistan, the use of solar energy for power generation is a relatively new experience. In recent months, Pakistan has shown a paradigm shift in its renewable energy policy and invested on mega power plants based on solar PV system. This paper reviews the recent exponential rise of using solar energy for power generation in Pakistan. The results of this paper will not only help in understanding and hence, curbing the power crisis in Pakistan, but will also be relevant to the other countries of the third world. [ABSTRACT FROM AUTHOR]

Increasing incentives for building integrated photovoltaic (BIPV) generation at local/major grid levels established it as a viable decentralized option promising large growth potential. BIPV systems – comprising photovoltaic (PV) modules installed on available building surfaces and downstream energy conversion devices – afford improvement of energy efficiency of buildings and partially or fully dispenses with the supply of centralized grid power. This paper presents a comprehensive techno-economic review, covering the technical as well as commercial aspects of microinverter technology. Advantages of microinverters over conventional inverters are detailed along with a discussion on economics of its installation in distributed solar generation systems. Different power converter topologies reported in the available literature are presented. The paper also reports the historical development of commercial microinverters and their present status in the Photovoltaic (PV) market. Survey of the available products from some of the technology leaders in the market has been done and their specifications are tabulated. The paper concludes with a discussion on the necessities of the next generation microinverters for increased penetration in the PV market. [ABSTRACT FROM AUTHOR]

The air conditioner should control the building sensible and latent load properly in order to provide the indoor comfort conditions. The conventional mechanical vapor compression system usually controls the latent load by the process of condensation of water vapor in which air is cooled below its dew point temperature and then reheated again up to the required supply conditions. The conditions where latent load is dominant these two processes i.e. overcooling and then reheating again will increase the consumption of electrical energy and emission of CO 2 remarkably. To avoid this wastage of primary energy and emission of harmful gases, desiccant based evaporative cooling system is a good alternative to traditional air conditioning system which is cost effective as well as environment friendly. It can be driven by thermal energy which makes a good use of solar energy which is free as well as clean. In this paper, a review of desiccant based evaporative cooling systems has been presented. The present study is undertaken from variety of aspects including background and need of alternative cooling systems, concept of conventional and desiccant based evaporative coolers, system configurations, operational modes, as well as current status of the desiccant based evaporative cooling technology. The review work indicated that the technology of desiccant based evaporative cooler has a great potential of providing human thermal comfort conditions in hot and humid climatic conditions at the expense of less primary resources of energy as compared to conventional cooling systems. Some modified and modern evaporative coolers have also been introduced in this paper. [ABSTRACT FROM AUTHOR]

The mitigations of global energy demands, climate change and energy related greenhouse gas effects are the most important factors in the modern days. However, renewable energy is one of the alternative sources which has the capacity to mitigate all the above. Among all the renewable energy sources, solar energy is one of the most abundant and the cleanest energy source. Different laboratories of the world have achieved different solar cell efficiencies, which are also discussed in the present paper. This paper presents the global solar PV developments, per capita values, government supportive invectives and policies of the top ten solar power producing countries. This paper also presents the investments of the global solar energy among the countries. Finally, through the study, it is found that these top ten leading countries are following fulfilment of their projections, supportive tariff rates, net metering, green certificates and government incentive policies as their instruments. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to study the positions of some European Union (EU) countries on the development of PV systems. After a review of the main support policies for PV systems in Europe, the specific situations of five representative countries (France, Germany, Greece, Italy and the U.K.) are examined, with the purpose of describing the main differences in their implementation of support policies adopted for PV systems. In particular, comparisons based on economic indexes such as the net present value (NPV) and the internal rate of return (IRR) are carried out for different sized PV systems, showing that in some situations support policies can be inconvenient for the PV system owner. The paper also shows that the best profitability for a PV system owner is obtained in those countries in which there is an active electricity compensation scheme. The comparative analysis carried out in this work could help: – to assess the impact of PV energy policies in European member states; – to predict how the PV market could evolve in the selected EU member states; – to gain an insight into the future of possible energy policies. [ABSTRACT FROM AUTHOR]

Energy economy restructuring at the city level is an essential prong in any strategy that aims to address the dual energy and climate change challenges. Cities form hubs of human activity that are accompanied by high levels of energy consumption and emissions but also contain existing resources and infrastructure to transition to a greener energy economy. This paper reviews efforts to date to define the ‘solar city’ concept and assessment methods for estimating the solar electric potential of an often neglected but vital city resource in energy matters – its rooftop real estate. From this review, an application of the solar city concept is formulated and an assessment method is offered for its investigation. An illustrative case study is provided, using the City of Seoul, South Korea. Representing nearly one-quarter of South Korea’s population and a one-third of its economic activity, the application of the solar city concept to the city can have significant consequences for the future energy development pathway of the municipality and the country (the metropolitan area of Seoul encompasses nearly one-half of the national population). The research demonstrates that a technical potential equivalent to almost 30% of the city’s annual electricity consumption can be supplied by widespread deployment of rooftop-based distributed photovoltaic systems. Using the methodology developed in the paper, we estimate that sixty-six percent of the annual daylight-hours electricity needs of the City of Seoul can be served by distributed solar power systems on a typical day. It is additionally found that considerable peak shaving is possible, lessening the pressure on the city’s electricity grid. These findings can be expected to extend to other large cities when the solar city concept is thoughtfully applied. [ABSTRACT FROM AUTHOR]

Solar energy is one of the cleanest forms of energy sources and considered as a green source of energy. Solar energy benefit ranges from low carbon emission, no fossil fuel requirement, long term solar resources, less payback time and other. However like other power generation sources, solar energy has also some Safety, Health and Environmental (SHE) concerns. This paper presents the overview of solar energy technologies and addresses the SHE impact of solar energy technologies to the sustainability of human activities. This paper will also recommend the possible ways to reduce the effect of potential hazards of widespread use of solar energy technologies. [ABSTRACT FROM AUTHOR]

Electric energy security is essential, yet the high cost and limited sources of fossil fuels, in addition to the need to reduce greenhouse gasses emission, have made renewable resources attractive in world energy-based economies. The potential for renewable energy resources is enormous because they can, in principle, exponentially exceed the world׳s energy demand; therefore, these types of resources will have a significant share in the future global energy portfolio, much of which is now concentrating on advancing their pool of renewable energy resources. Accordingly, this paper presents how renewable energy resources are currently being used, scientific developments to improve their use, their future prospects, and their deployment. Additionally, the paper represents the impact of power electronics and smart grid technologies that can enable the proportionate share of renewable energy resources. [ABSTRACT FROM AUTHOR]

This paper aims to provide the current state of the art of solar adsorption refrigeration systems operating with the single-bed intermittent cycle (also known as basic cycle). A comprehensive literature review has been conducted and it was concluded that this technology, although attractive, has limitations regarding its performance that seem difficult to overcome. Therefore, new approaches were identified to increase the efficiency and sustainability of basic adsorption cycles, like the development of hybrid or thermal energy storage adsorption systems. A survey of the developments in these new research trends is also presented in this paper. It shows that there are simple adsorption cycles which can be attractive alternatives not only to serve the needs for air-conditioning, refrigeration, ice making, thermal energy storage or hybrid heating and cooling purposes, as standalone or integrated systems, but also to meet the demands for energy conservation and environmental protection. [ABSTRACT FROM AUTHOR]

This paper reviews the utilization of solar thermal energy technology in assisting coal-fired power plants retrofitted with post-combustion carbon capture (PCC). The focus is on compensating the so-called 'energy penalty' imposed on the power plant output by the introduction of PCC plant operations. The integration of solar thermal energy can offset the power plant output reduction due to the PCC installation by totally, or partially providing the energy requirement of the carbon capture plant. The main process integration approaches proposed in this regard are reviewed; their advantages and drawbacks are discussed considering technical and climatic factors. The paper also discusses the merits of this hybridization of power, capture and solar plants as a transition solution for future low-carbon power generation. [ABSTRACT FROM AUTHOR]

Solar air heaters form the major component of solar energy utilization system which absorbs the incoming solar radiation, converting it into thermal energy at the absorbing surface, and transferring the energy to a fluid flowing through the collector. The efficiency of flat plate solar air heater has been found to be low because of low convective heat transfer coefficient between absorber plate and the flowing air which increases the absorber plate temperature, leading to higher heat losses to the environment resulting in low thermal efficiency of such collectors. Artificial roughness in the form of repeated ribs is the most effective and economic way of improving the thermal performance of solar air heater. This paper presents an extensive review on the research carried out on artificial roughened solar air heater ducts. The objective of this paper is to review various studies, carried out on thermal as well as hydraulic performance of artificial roughened solar air heater ducts. The review presented in this paper will be useful for the researchers working in this area. [ABSTRACT FROM AUTHOR]

Abstract: Solar energy sources, having the potential to provide energy services with zero emissions of air pollutants, have become more economically attractive with technological improvements. Organic Solar cells promise to be a significant contributor to our future energy system with suitable efficiencies and low cost. The foundation, basic principles, material requirements and device operation mechanism of organic solar cells has been already reviewed by various authors. This paper highlights the use of Schiff bases and their metal complexes as Photovoltaic materials. Schiff bases having potential Photovoltaic characteristics are also discussed in this paper. Major developments in this field over the past few years and recent research have also been briefly discussed. [Copyright &y& Elsevier]

This paper proposes a probabilistic pricing which achieves efficient operation of and investment in ramp-service providers in power systems with a large amount of wind or solar generation. The proposed pricing differs from the existing literature in that it focuses exclusively on the efficient dispatch of electrical energy with no exogenous consideration of the need for reserves or balancing services. The proposed optimal dispatch task determines both the efficient level of any preventive actions taken before a contingency event occurs and the efficient response of the power system - i.e., corrective actions - once an event occurs. We show analytically that the efficient dispatch outcome can be achieved in a decentralized market mechanism provided the market participants are profit-maximizers and price-takers. We show how the total economic benefit of an investment can be decomposed into two components (a) the normal dispatch cost benefit and (b) the economic value of the investment in contributing ramp service to the power system. In order to study different aspects of the probabilistic pricing, the IEEE 30-node example system is deliberately modified. The results show the efficiency of the proposed pricing and the use of the investment model to assess the economic value of ramp-service providers. [ABSTRACT FROM AUTHOR]

The rapid increase in energy demand and the limited resources of fossil fuel as well as the environmentally damaging effects, drive the world to find new options for sustainable electricity generation, which is represented by renewable energies. Concentrating solar power (CSP) is one of the most promising technologies in the field of electricity generation to tackle this issue with a competitive cost in the future. This paper presents an investigation of the potential of implementation of CSP plants in Libya. The socio-economic context, current energy situation of the country and different types of CSP plants are discussed. Moreover, an assessment of site parameters required for CSP plants including solar resources, land use and topography, water resources and grid connections are investigated in detail. In addition, thermo-economic simulation of a 50 MW parabolic trough power plant is performed. The simulation is conducted based on meteorological data measured by the weather station installed at the Centre for Solar Energy Research and Studies (CSERS) in Tajoura city. The performance results are compared with the reference plant Andasol-1 in Spain. Even though the proposed plant is located on the North coast where solar resources are at their minimum compared with other regions of the country, the outcome of the study proves that Libya is not only suitable but it can be economically competitive in the implementation of CSP technology. [ABSTRACT FROM AUTHOR]

This paper documents the production, upgradation and utilization aspects of solar driven pyrolysis products namely bio-oil, biochar, and pyrolytic gas. Scattered literature information on solar thermochemical pyrolysis of different kinds of biomass reviewed holistically and consolidated for a proper insight to enhance the utilization of pyrolysis products in various applications. The major influencing parameters for better yield of pyrolysis products are identified as reaction temperature, heating rate, biomass particle size, reaction catalyst and type of biomass. All the three products (bio-oil, biochar, and pyrolytic gas) could be employed as fuel candidates in various sectors including transportation and industrial heating appliances. It is emerged from the study that the biomass-derived bio-oil must be upgraded for its use in compression ignition (CI) engines. However, the raw bio-oil could directly be used in industrial heating appliances such as furnaces and steam generators. A comprehensive insight is provided with comparative assessment of performance and emission characteristics of pyrolysed bio-oil fueled CI engines in order to address the research challenges and employ the engine's efficiency enhancement technologies in near future. [ABSTRACT FROM AUTHOR]

Solar energy is increasingly attracting the attention of industry and academia. This heightened focus is mainly motivated by the challenge to contribute to fossil fuels' alternative and to limit the pollution of environment caused by their emissions. The number of researches focusing on solar photovoltaics is continually increasing. The behavior of a photovoltaic (PV) cell/module may be deduced via its current–voltage (I–V) characteristic which depends on its circuit model parameters. Whilst, the extraction of appropriate circuit model DC parameters is crucial to carry out precise performance investigations and control studies on solar PV systems, it remains highly constrained nonlinear non-convex optimization problem. The main objective of this paper is to review the existing research works on PV cell model parameter estimation problem and to assess the performance of the newest approaches. Based on the conducted review of more than 100 methods published over the past 7 years, the recommendations provided for future research are an important goal that will improve the methods of research in this area. In addition, this article implements two real models (single-diode and double-diode) and examines their accuracy to draw the current–voltage (I– V) and power–voltage (P–V) characteristics. [ABSTRACT FROM AUTHOR]

Solar simulators are used to test components and systems under controlled and repeatable conditions, often in locations with unsuitable insolation for outdoor testing. The growth in renewable energy generation has led to an increased need to develop, manufacture and test components and subsystems for solar thermal, photovoltaic (PV), and concentrating optics for both thermal and electrical solar applications. At the heart of any solar simulator is the light source itself. This paper reviews the light sources available for both low and high-flux solar simulators used for thermal applications. Criteria considered include a comparison of the lamp wavelength spectrum with the solar spectrum, lamp intensity, cost, stability, durability, and any hazards associated with use. Four main lamp types are discussed in detail, namely argon arc, the metal halide, tungsten halogen lamp, and xenon arc lamps. In addition to describing the characteristics of each lamp type, the popularity of usage of each type over time is also indicated. This is followed by guidelines for selecting a suitable lamp, depending on the requirements of the user and the criteria applied for selection. The appropriate international standards are also addressed and discussed. The review shows that metal halide and xenon arc lamps predominate, since both provide a good spectral match to the solar output. The xenon lamp provides a more intense and stable output, but has the disadvantages of being a high-pressure component, requiring infrared filtering, and the need of a more complex and expensive power supply. As a result, many new solar simulators prefer metal halide lamps. [ABSTRACT FROM AUTHOR]

Grid electricity generation in Nigeria has been unstable for a long time now. With respect to her continued dependence on oil and gas and seasonal variations on water level for hydropower, immediate reliable and steady electricity generation in the country is not guaranteed. Incorporating alternative source of energy like solar is a solution. Solar Chimney technology is not yet technically and economically mature, as investment on it is still low, thereby posing more financial risks at least at the megawatt capacity. Photovoltaic and Solar Thermal technologies are technically and economically more established, but they can only ensure 24-h power supply with the aid of energy storage systems. Solar thermal value addition is on its propensity for thermal energy storage and hybridization with liquid fuels at commercial capacity. Hence, due to technology advancement and the country's high direct normal irradiation potential, concentrating solar power is the more suitable solar power technology for commercial electricity generation in Nigeria. In this paper, concentrating solar power technologies are analysed under operational, environmental and social conditions in Nigeria using data from desktop survey to determine the most suitable technology for solar thermal electric power plant. It is observed that the technical maturity of parabolic trough concentrator distinguishes it for preference to all other technologies and would exert moderate pressure on land requirement even though, it is the most expensive and water demanding technology. In terms of unit cost of electricity and water usage capabilities, parabolic dish concentrator is least expensive and uses least water but lacks proven commercial application. Solar tower is technically simpler and possesses better thermodynamic properties than the rest but its low installed capacity increases its financing risk. Hence, the trough system is the most suitable for immediate and medium term projects given its proven technology maturity and flexible financing mechanism. [ABSTRACT FROM AUTHOR]

Building integrated photovoltaics (BIPV) is one of the most promising contributors to net-zero energy buildings, while also increasing the aesthetic value of the built environment. Nevertheless, it currently is predominantly operating in a niche market of ~ 1% of the global photovoltaics market. In this paper we provide a thorough Multi Criteria Decision Analysis of the BIPV ecosystem (markets, stakeholders, and policy and legislation) in various European countries, i.e. the Netherlands, France, Germany, Switzerland, and the United Kingdom. Environmental legislation and building requirements were found to be similar, as all countries have the European Energy Performance of Buildings Directive (EPBD) in common. It was found that implementation of the EPBD differs per country, evidenced by different support schemes in effect. Also, harmonisation of building codes hampers BIPV development. The analysis provides a basis for developing a BIPV ecosystem, which may differ per country. Also, clearly the BIPV sector crosses national boundaries, and should therefore be reviewed and developed from an international perspective. [ABSTRACT FROM AUTHOR]

Off-grid solar electric power is a promising technology for remote regions in rural Africa where expansion of the electricity grids is prohibitively expensive. Using household data from a target region of an off-grid solar promotion program in the Kénédougou province in Burkina Faso, this paper explores the role of quality-verified branded solar home systems (SHS) versus non-branded ones. We find that the adoption rate of non-branded SHS is considerably higher at 36% compared to 8% for branded SHS. We compare potential quality differences as well as the cost-effectiveness of branded and non-branded solar products. We show that non-branded SHSs offer a similar service level as branded solar, that they do not fall behind in terms of consumer satisfaction and durability, and that non-branded products are more cost-effective. These findings suggest that promotion programs and branded solar products do not seem to be necessary in Burkina Faso and might also not be needed to establish sustainable off-grid solar markets elsewhere provided that non-branded products are available. The challenge however is to reach the very poor who are unable to bring up investment costs for any electricity. [ABSTRACT FROM AUTHOR]

Winemaking is a global industry that needs to advance with the times taking into consideration the developing drinking needs, tastes of human beings and the growing demand on the world's renewable energy sources. Climate changes have brought nowadays challenges of energy requirements, subsequent emissions and the detrimental effects facing the winemaking industry and mankind. Given its energy requirements, concomitant emissions and the pernicious effects, winemaking industry should bear the brunt of improving energy utilization efficiency and promoting the development and adoption of renewable energy utilization technologies. Various kinds of renewable energy are being used in winemaking industry worldwide, especially solar energy in the form of solar thermal and solar photovoltaic, which offer a clean solution to fossil fuels shortage and pollutant emissions caused by or involved in winemaking processes. The objective of this paper to present challenges facing solar energy utilization in winemaking by summarizing the status of solar energy utilization in wineries worldwide, by outlining the current solar energy profile of these wineries and by stressing the existing and potential application aspects of solar energy in winemaking. Considering the more rapid development of PV industry, PV chain and economic feasibility are analyzed. By taking China as an example, the comparison and asymmetry between PV production and active solar-related winemaking are stressed aimed at appealing to winemakers and policymakers to turn more to renewable energy like solar energy. Based on that, essential suggestions are provided, which are expected to extend solar energy systems for subsequent contributions to energy conversation, environmental protection and reduction of land occupation. [ABSTRACT FROM AUTHOR]

Solar and wind energy are inherently time-varying sources of energy on scales from minutes to seasons. Thus, the incorporation of such intermittent and stochastic renewable energy systems (ISRES) into an electricity grid provides some new challenges in managing a stable and safe energy supply, in using energy storage and/or 'back-up' energy from other sources. In such cases, the ability to accurately forecast the output of “unpredictable” energy facilities is essential for ensuring an optimal management of the energy production means. This review syntheses the reasons to predict solar or wind fluctuations, it shows that variability and stochastic variation of renewable sources have a cost, sometimes high. It provides useful information on the intermittence cost and on the decreasing of this cost due to an efficient forecasting of the source fluctuation; this paper is for engineers and researchers who are not necessarily familiar with the issue of the notions of cost and economy and justify future investments in the ISRES production forecasting. [ABSTRACT FROM AUTHOR]

The continuous and increasing usage of fossil fuels is adversely impacting the environment and also presents economical and geo-political challenges for policy makers around the world. Solar energy is one of the forms of renewable energy resources which is freely and abundantly available on the earths' surface and hence could be a very good potential alternative to fossil fuels. Apart from directly generating electric power (using solar photovoltaic cells), more and more attention is being paid to the use of solar thermal collectors for heating various fluids for applications ranging from space heating/cooling, process heating, steam generation etc. Such solar thermal collectors are generally are of conventional type, having a 'black' surface-based absorption of solar irradiation. In order to improve the overall efficiency of such collectors, a new type of direct absorption solar collectors (DASC) have been proposed recently. In DASC, a nano-sized particle are added to the heat transfer fluid and due to these particles the optical and thermo-physical properties of the fluid improves, and it is able to directly absorb the solar irradiation, eliminating the need of a conventional 'black' surface. This review paper presents a state-of-art of such nanoparticles-laden fluid-based solar thermal collectors, and focuses on factors like volume fraction, material and shape of the nanoparticle and mass flow rate of the fluid which affects the performance of the nanoparticles-laden fluid-based-solar thermal collector. In particular, special attention has been given to the studies involving the effect of using nanoparticles of various classes of materials – metallic, core/shell, graphite – on the overall optical properties of the working fluid (nanoparticles-laden fluids). [ABSTRACT FROM AUTHOR]

The solar collector is the heart of any solar energy collection system designed for operation in the low to medium temperature ranges. So, an efficient design of solar collector system, giving optimum performance is required. Though system performance is optimized by many different techniques, however, intelligent system design is an useful technique to optimize the efficiency of such systems. One of the intelligence techniques is Artificial Neural Network (ANN), and it is used in modeling, simulation and control of the system. ANN tool is faster and more accurate to solve complex and nonlinear problems as compared to other conventional techniques. ANN technique is applied in the field of Science, Engineering, Medicine, Defense, Business and Manufacturing etc. The main task of ANN tool is training of structure, which is done by collected experimental data of solar energy systems and in this method separate programming is not required as in other conventional methods. The aim of this study is to review the applications of ANN to predict the performance of solar energy collector and to identify the research gap for future work. Published research works presented in this paper, show that the ANN technique is very appropriate tool to predict the performance of solar collector systems [ABSTRACT FROM AUTHOR]

Accurate information on global solar radiation is essential to design and operate the systems that are based on solar energy. However, global solar radiation measurement is very rare while the measurements of other meteorological parameters such as air temperature, relative humidity, sunshine duration and precipitation are common in meteorological stations all around the world. Therefore, modelling global solar radiation is an important issue to fill the gaps in database and to estimate global solar radiation in places where global solar radiation measurement is not available. There are many different approaches in the literature for modelling global solar radiation. Two new methodologies are presented in this paper to develop parametric models for estimation of daily global solar radiation based on sunshine duration and relative humidity as well as a review of fourteen different already exist parametric models which are based on air temperature, maximum temperature, minimum temperature, precipitation, sunshine duration and relative humidity. The proposed models improve the estimation results of the other fourteen models with average mean absolute error (MAE) of 0.947 MJ/m 2 for Adana station, 1.086 MJ/m 2 for Göksun station, 1.074 MJ/m 2 for Tarsus station and 1.060 MJ/m 2 for whole study area. Hence, the proposed models which significantly approximate to measurements from pyranometers can be useful for the modelling global solar radiation in Eastern Mediterranean Region. [ABSTRACT FROM AUTHOR]

Solar Energy is available in abundance and can be easily extracted using solar cells along with regular maintenance of solar panels. However, the efficiency of solar cells which is fairly low, is further affected by factors such as orientation of the panel, shade, wind speed, ambient temperature, precipitation and dust deposition. Especially, the maintenance of solar panels is challenging on account of soiling. Presently, manual and water-based cleaning solutions are generally used to remove the debris accumulated on the panels. In this paper, a detailed review of soiling prevention methods is presented with a view to increase the energy capture from solar panels. The technical details of an indigenously developed automated water-free cleaning device to remove soiling over the solar panels, is then discussed. The energy capture over the course of a month for PV panels regularly cleaned using automated solar panel cleaning solution is compared with that of the energy capture using soiled panels in a local solar panel installation, and the increased yield is measured. [ABSTRACT FROM AUTHOR]