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Abstract This research is investigating the possibility of using heat stored in solar ponds for salt drying. At present, Pyramid Salts, a salt producing company located in the north of Victoria, Australia, use electric heaters to heat ambient air from around 20 °C to around 70 °C in their salt crystallizers for salt drying. This research paper aims to develop a solar PV driven heat pump coupled with a solar pond to supply necessary hot air. According to the collected data solar pond performance in Pyramid Hill indicates that heat will be available at the bottom of the pond between 35 °C to 50 °C (winter to summer). Coupling the salinity gradient solar pond with the heat pump is the novelty of this research paper. The heat pump's evaporation boosts from ambient temperature to available solar pond heat (40 °C) and above 24/7 all year around. As a result, the amount of electrical energy saving in this project has been estimated to be about 1 GWh per year. In this work, the preliminary data on the developments of salinity, temperature, and turbidity profiles will be considered and discussed. [ABSTRACT FROM AUTHOR]

Abstract Despite a significant progress in electrification over the last decade, more than 1 billion people have no access to electricity, and about 3 billion use solid fuel or kerosene for cooking and heating purposes. More than 95 % of them live in sub-Saharan Africa or developing Asia, and around 80 % are situated in rural areas. Conventional approach to power supply such as transmission grid extension is not economical due to high investment and connection costs. Technological progress has shifted down capital costs of renewable off-grid solutions. However, in the most cases, it is not enough to reach feasibility of these solutions due to weak investment conditions and weak purchasing power of the local population in these areas. The choice of business model can have a vital role in bringing electrification and connectivity to rural areas, providing flexibility and adaptability of the technology to the market conditions. Analysis of existing literature on business models for off-grid solutions concludes that the model for rural areas in developing countries should be more service oriented, be scalable to various use case scenarios, should provide good risk balance between customer and provider, and should enable transparency and quality of service. This paper analyses recent developments in off-grid system solutions for sub-Saharan Africa and provides classification of business model innovations. Based on the analysis, the paper proposes an innovative business model for Fusion Grid project, scalable mini-grid integrated with connectivity solution. Feasibility of the project is tested for three different cases, depending on the type of the rural community. Results suggests that combining micro-grid based power supply and internet connection as one service can contribute to a viability of the project, and, furthermore, can contribute to achieving global electrification goal. [ABSTRACT FROM AUTHOR]

Abstract Climate change and global warming are currently the biggest threat to human society. In Iranian households, buildings expend 33% of the yearly energy consumption. The potential of renewable energy sources in Iran is high and Iranian government is taking steps to increase the use of renewable energy sources. This paper examines the use of renewable energy in two major city buildings in Iran. In this paper, solar radiation in two cities (Tehran and Yazd) is analysed. The average annual sum of solar irradiation in Yazd is 2200 kWh/m2 and in Tehran, the amount is 2000 kWh/m2 [1]. The major task in this paper is to quantify the impact of geographical region and to evaluate the viability of implementing renewable systems in buildings in Iran. To reach this end, the annual average solar radiation is calculated in each city. Hourly Analysis Program is used to design each building and calculate their respective heating and cooling loads. Photovoltaic solar systems and solar-thermal systems are designed for both of the buildings. It is seen that, although Yazd has hot and arid climate compared to Tehran, the cooling and heating load in the building in Tehran is higher, and the higher solar radiation in Yazd reduces the number of solar panels required for the designed building. However, the difference is not significant. It is assessed that in order to have more efficient systems, the grid infrastructure in Iran should be upgraded to enable applying large-scale renewable energy systems for buildings in a neighbourhood. [ABSTRACT FROM AUTHOR]

This paper gives a comprehensive review about the recent advances related with the application of the nano fluid in the heat pipe solar collectors. Papers reviewed including theoretical, numerical and experimental up to date works related with the nanotechnology applications in this type of the solar collectors. A lot of literature are reviewed and summarized carefully in a useful table (Table 1) to give a wide overview about the role of the nano fluid in improving the heat pipe solar collectors. It was found that the use of the nano fluid in the heat pipe solar collectors can play a significant role in increasing the efficiency of these devises. [ABSTRACT FROM AUTHOR]

Cities, accounting for more than 3/4 of global final energy consumption, are equipping themselves with governance tools to improve energy efficiency. In Europe, urban energy policy has adopted, only recently and voluntarily, the Sustainable Energy Action Plans (SEAP), following the European Strategy 20-20-20. Italy, country most sensitive among European ones, accounts for 53% of SEAPs signatories. In order to evaluate how urban energy system in Italy can match sustainability European goals, it is necessary to analyse the technological options promoted by the energy policies for the urban environment. The paper presents the state-of-art of Urban Energy Planning in Italy, focusing on the implementation of Solar Energy technologies, and their role in new urban energy strategy instruments, i.e. SEAP, to promote renewables deployment. Carbon emission avoidance interventions planned by Italian big cities were analysed, highlighting the chosen Solar Energy technology. The aim of this paper is to discuss and evaluate the differences of solar energy harvesting in Italian urban scenarios, taking into account geographical and morphological constraints, and to compare the forecasts for 2020 and 2030scenarios, in accordance with European and National laws in force. [ABSTRACT FROM AUTHOR]

This paper presents and evaluates initiatives taken in Morocco to reduce wood consumption, improve energy efficiency and reduce deforestation due to the operation of hammams (Turkish baths). First, the paper examines the vernacular energy systems used in heritage hammams and their lessons of sustainability. Second, it presents the problems associated with the new hammam furnaces and how they replicate vernacular systems. Third, the various initiatives for more energy efficient systems are presented. These include hybrid solar/biomass hammam systems. The paper evaluates the opportunities for addressing local and global concerns over deforestation and CO 2 emissions and discusses various difficulties and challenges. [ABSTRACT FROM AUTHOR]

This paper explores Kenya's central highlands rural community's sources of energy choices’ in the last three decades. The paper tracks the changes in sources of energy (firewood, charcoal, kerosene, car battery and dry cells) up to the option of using the solar homes systems. In Kenya, the demand for clean energy for both industrial and domestic activities is on the rise. Currently, the energy for the industries and urban areas is derived largely from petroleum and hydroelectric power. On the other hand, for the low-income earning rural community in the Kenya's central highlands, firewood is however the major source of energy for most domestic activities. Considering that arid and semi-arid regions constitute over 80% of the country, the demand for firewood for instance impacts the natural ecosystems and disrupts the natural nutrient cycling. [ABSTRACT FROM AUTHOR]

For active solar systems, such as solar collectors and PV panels it is important to estimate the possible thermal or electric energy production. The energy output of these devices depends on several factors. In this paper different models for estimating the available solar radiation were analyzed. The models selected for evaluation were the Liu-Jordan, the Hay and the Reindl et al. models. There are studies evaluating such models, but evaluations were not performed for Central and Eastern European locations, only for regions with different climatic conditions. Present study focuses on the Central and Eastern European region with it's specific continental climate. In order to evaluate the models, a major city of the region, Budapest, was selected. In Eastern Europe usually only the monthly and yearly values of solar radiation are available and applied in engineering practice. However, in many cases more detailed data are required. Hence the aim of this paper is also to highlight the importance of available daily data for modeling. For solar collectors and PV panels, the optimal orientation is to the south and the optimal tilt angle is assumed to be approximately 45° in the region. The calculated daily values were compared to measured data. The solar radiation was measured on a 45° tilted, south oriented surface in Budapest. The dataset used for the global radiation calculations was provided by the Hungarian Meteorological Service. [ABSTRACT FROM AUTHOR]

In this paper, a radiant heating system is introduced, which was developed based on the model of capillary radiant terminal (CRT) combined with solar thermal energy usage and phase change thermal storage (PCTS) technology. The aim of this work is to investigate the feasibility and the stability of the system that could be applied into residential buildings in the actual construction. The indoor thermal environment based on the tested system is analyzed in this paper. According to the weather condition of Xi’an, the winter average solar insolation and the ambient temperature were 9.14 MJ/m 2 and 8.9 o C, respectively. The experimental results show that the average heating capacity of the designed system was about 1.08 kW for a typical sunny day in the winter. It was higher than the simulated heating load. As a result, the indoor air temperature reached 18 o C, which sufficiently met the requirement of indoor thermal condition. It is also found that the indoor air temperature distributes uniformly and the maximum difference of the vertical temperatures was less than 3.2 o C. This indicates that the indoor thermal comfort of the test room can be classified in the comfort level of A. [ABSTRACT FROM AUTHOR]

In this paper, a radiant heating system is introduced, which was developed based on the model of capillary radiant terminal (CRT) combined with solar thermal energy usage and phase change thermal storage (PCTS) technology. The aim of this work is to investigate the feasibility and the stability of the system that could be applied into residential buildings in the actual construction. The indoor thermal environment based on the tested system is analyzed in this paper. According to the weather condition of Xi’an, the winter average solar insolation and the ambient temperature were 9.14 MJ/m 2 and 8.9 o C, respectively. The experimental results show that the average heating capacity of the designed system was about 1.08 kW for a typical sunny day in the winter. It was higher than the simulated heating load. As a result, the indoor air temperature reached 18 o C, which sufficiently met the requirement of indoor thermal condition. It is also found that the indoor air temperature distributes uniformly and the maximum difference of the vertical temperatures was less than 3.2 o C. This indicates that the indoor thermal comfort of the test room can be classified in the comfort level of A. [ABSTRACT FROM AUTHOR]

In this paper, a solar hybrid desiccant air conditioning system, which combines the technologies of two-stage desiccant cooling system and geothermal heat pump together, has been configured and theoretically analyzed. The hybrid system mainly includes a two-stage desiccant cooling system with design cooling capacity of 80 kW, a geothermal heat pump for fresh air handling with 75 kW in nominal cooling capacity, a geothermal heat pump for capillary radiation terminal with cooling capacity of 244 kW, an evacuated tubular solar collector array of 530 m 2 , a hot water storage tank and a cooling tower. Performance model of the system has been created in TRNSYS simulation studio. The aim of this paper is to evaluate the performance of the solar hybrid air conditioning system, thereby providing useful data for practical application in the demonstration project. Simulation results show that, under typical weather condition, the solar driven desiccant cooling unit can achieve an average cooling capacity of 70 kW, which contributes 31.4% of the cooling capacity provided by the hybrid system. Corresponding average thermal COP is about0.83 under Shanghai weather conditions. [ABSTRACT FROM AUTHOR]

The current heat treatment processes make use of electricity or fuel for generating heat. Solar energy is available in abundance in the states of Rajasthan and Gujarat in India. Annual global solar radiation of about ≥2400 kWh/m 2 is received in these regions. Use of the abundant solar thermal energy in heat treatment of metals would saveenergy and fuels. In view of this a concept of solar convective furnace system is described in this paper. As a starting point, heat treatment of aluminium is considered. For this system, requirements of industrial furnace are taken as basis.A scale-down retrofitted furnace is designed and analysed.The importance of different process stages like, solar thermal energy absorption, storage and utilization in design of such a system is presented.A thermodynamic analysis is performed to derive requirements for the achievement of a uniform heating at a pre-determined rate. Control strategy to meet the requirements is worked out. Air flow profile in the furnace is analyzed using CFD as a tool. Laser Doppler Velocimetery technique is used for measurement of velocity in a Plexiglas model of the scale-down furnace. Flow analysis using theadopted CFD tool shows non uniformities in air flow profile. To counter this, further modifications and improvements in the furnace structure are suggested. Evaluation of Open Volumetric Air Receiver (OVAR) using installed solar air tower simulation facility is also presented in the paper. [ABSTRACT FROM AUTHOR]

The aim of this paper is to provide a comparative energetic and economic assessment of two solar tower power configurations; the molten salt (MS) and the direct steam generation (DSG) technologies in order to study the appropriate configuration for Algerian climate conditions. For this, Tamanrasset has been chosen as representative site to simulate the proposed solar tower power plant configurations. The first section of this paper analyses the conversion of the solar energy into electric energy. The NREL's SAM software (Solar Advisor Model) is used to evaluate the energetic performances of the two plant configurations in the proposed site and also to study their economic feasibility in the second section. [ABSTRACT FROM AUTHOR]

There are at least three types of photovoltaic cells derived from raw materials, which have not been differentiated in most of the previous literature. From a global perspective, we focus on a mainstream product in the photovoltaic energy market: crystalline silicon photovoltaic cells (CSiPVCs). This paper delineates the technological developing trend and global geographical distribution of CSiPVCs. Furthermore, the specific technological evolution route is emphasized on a national level. In terms of policy implication in China, and particularly in the context of China's recent predicament in the international PV market, the paper establishes a framework to disclose, in depth, the gap between China and technologically advantageous nations. Policy suggestions for China are proposed as well. [ABSTRACT FROM AUTHOR]

This paper presents the preliminary operational results of two 3.5 kWp CPV systems using triple junction III-V solar cells and a two-axis tracking mechanism. The plant is installed in the campus of the Università Politecnica delle Marche (Ancona, Central Italy). The concentration optics consists of a primary Fresnel lens and a secondary reflective optics with an overall geometrical concentration ratio of 476 X. An experimental measurement setup acquires the main plant operating and ambient quantities; the paper reports the first months of plant operation with particular focus on the influence of the available radiation and the ambient temperature on the performance of the system. The electric output has a linear trend with the available direct normal radiation while ambient temperature has a minor effect on the performance of the CPV systems; also the influence of the Air Mass coefficient is reported. [ABSTRACT FROM AUTHOR]

This paper presents a methodology associated to a set of explicit equations aimed to translate point-to-point the generated power to standard test conditions and its application to a real situation. Such equations are employed for monitoring and diagnostic of grid connected photovoltaic systems. The proposed method is based in the data analysis through statistical methods and it allows diagnosis or detection of instant decreases of generated power. The Experimental results are compared with other procedure of characterization of the nominal power of large photovoltaic generators under real operation conditions which are based on protocols similar to the one proposed in this paper. Results show differences less to 3% between both methods. In conclusion, the methodology presented is useful for real time diagnose of power decrease, when variation of maximum power with temperature is not known or in cases where catalog parameters are not available. [ABSTRACT FROM AUTHOR]

The solar updraft power plant is a promising technology for harnessing the solar energy and many researchers developed the plant design to improve its low efficiency. Using a sloped solar collector is one of the novel techniques that improves the plant efficiency in higher latitudes and reduce its capital cost. In this paper, a pilot Sloped Solar Updraft Power Plant (SSUPP) is constructed in the campus of mechanical engineering department of Damascus University in Syria. Thermometers were installed in the sloped solar collector to measure glass, air, and absorption layer temperatures along the collector. Solar radiation, ambient air temperature as well as air velocity inside the chimney were also recorded. These data were taken every 10minutes throughout the year 2012 to investigate the performance of the SSUPP. In this paper, the effect of the average monthly recorded values of solar radiation and ambient temperature on the prototype performance were analyzed in all weather conditions and the changes in sloped solar collector outlet temperatures were investigated. The results show that the difference between the ambient temperature and the chimney inlet temperature is almost the same in winter and summer seasons leading to a conclusion of the advantage of having an inclined solar collector in the SSUPP. [ABSTRACT FROM AUTHOR]

Abstract: In the last decade many studies have been carried out on low temperature solar compound parabolic collectors (CPC) that are able to collect solar direct and diffuse radiation without the need of a tracking system, especially if coupled with small scale Organic Rankine Cycles for electricity and heat combined production. This paper presents a study on a thermal power plant that uses an expansion device driven with pressurized vapor generated with the heat collected by a CPC solar field. The numerical model of the expansion device was developed with the simulation tool AMESim v.12 and allowed the simulation of the indicated cycle of this machine for the evaluation of delivered power, isentropic efficiency and specific working fluid consumption. At the same time in this paper an analytical model of the evacuated solar CPC is presented for the evaluation of the collected heat as a function of sun incidence angle, external temperature, inlet carrier fluid temperature and mass flow rate. These two models were used in conjunction for the analysis of the electricity that may be generated as a function of the ambient and working conditions. This study was performed in steady state conditions and with several working fluids to evaluate the power that would be delivered by a given displacement expander rotating at a fixed speed. The results are given in terms of delivered power, thermal efficiency and amount of collecting surface needed for a given displacement expansion machine, calculated for several working fluids and different operating conditions. [Copyright &y& Elsevier]

Abstract: The market for small Solar CombiSystems (SCSs) is penalized by its lack of common performance test method. The methodology proposed in this paper is based on the SCSPT procedure which tests each combisystem as a whole system on a semi-virtual test bench. Test results are used to identify a “Gray Box” model of the tested SCS, which includes an Artificial Neural Network. This model can then simulate the behavior of the system for any climate and any building. Results of all those simulations are finally used according to the FSC procedure in order to characterize the tested SCS performances with a simple curve. An experimental study of this methodology with two real SCS is presented in this paper. [Copyright &y& Elsevier]

Abstract: This paper introduces the biggest solar cooling system in China. The solar cooling system is applied to a campus library in Hainan Island, which is the furthest south province in China. Some important factors, such as scheme selection, supplementary energy resource choice, chiller type comparison, solar collector selection, system configuration, operation and control strategy determination etc., are mainly discussed in this paper. The project was finished in 2011 summer and an on-line monitoring system was installed to know how the system operates. Some primary technical and economic analysis is made and some suggestions about how to promote solar cooling system in China are also put forward in this paper. [Copyright &y& Elsevier]

Abstract: Solar PV systems have evolved from small stand-alone applications through residential and commercial systems to MW-scale installations and groups of systems that feed significant energy into the utility grid. High PV penetration levels create a number of challenges for the management of the operation of the utility grid. This paper will cover the current and historic status of the integration of renewable energies into utility grids over a variety of global regions. This includes grid control and network planning. The technology for the integration of PV is described including the codes and standards governing the utility interactivity requirements. This will include short term dynamic responses as well as power ramp rates. Geographic, technological, and meteorological factors will be discussed. The coordination of meteorology and energy production is a key factor that is examined in detail including real world data. The paper includes a discussion of future utility grid features to support increasing levels of PV and other renewable generation sources. [Copyright &y& Elsevier]

Abstract: In this paper, we show that the association of the PI regulators for the speed and stator currents with a control strategy using the linearization by state feedback for an induction machine without speed sensor, and with adaptation of rotor time constant powered by a solar photovoltaic energy. The solar photovoltaic energy nowadays, is one of the renewable energies sources present in various domains of applications. Moreover, the photovoltaic generator (PVG) output voltage depends of several climatic factors, such as the irradiations and the temperature. To overcome these problems, one must carries out an adequate sizing and exploits the maximum power available at the level of the (PVG). Thus the proposed structure in our work is constituted of one PV generator associated to a (DC/DC) converter controlled by using a technique of maximum power point tracker (MPPT). To adapt the rotor time constant, we proposed fuzzy tuning mechanism based on the reactive power of the machine in the permanent regime. The rotor speed is estimated by using the model reference adaptive system approach (MRAS). This method consists of using two models: The first is the reference model and the second is an adjustable one in which two components of the stator flux, obtained from the measurement of the currents and stator voltages are estimated. The estimated rotor speed is then obtained by cancelling the difference between stator-flux of the reference model and those of the adjustable one. Satisfactory results of simulation are obtained and discussed in this paper to highlight the proposed approach. [Copyright &y& Elsevier]

Abstract: This paper presents the research of a high frequency, high efficiency Solar inverter using silicon carbide power semiconductor device. Compared to silicon power devices, the silicon carbide power device is more suitable for solar power inverter due to its good electric characteristics. This paper presents the design of sic power semiconductor device based solar inverter. The experiment results of a 1kW silicon carbide JFET based inverter showed about 3% efficiency improvement by a silicon carbide JFET-based inverter over silicon IGBT based inverter. [Copyright &y& Elsevier]

Abstract: Efficient light trapping is essential for silicon thin-film solar cells. Excellent light trapping for silicon thin-film solar cells is achieved with randomly textured superstrates (TCO and/or glass). Due to a continuous and broad variation of occurring structure sizes in such textures, their optical simulation is challenging. In this paper we introduce an approach to establish a methodology for 3D optical simulation of silicon thin-film solar cells on randomly textured superstrates. The approach includes three steps. In a first step a fabricated structure is analysed to identify its typical geometric features. In a second step the single geometrical features are optically simulated using the rigorous coupled wave analysis (RCWA). The third step includes an investigation of how the results of the single features can be combined to describe the optical characteristics of the complete random structure. In this paper we concentrate on the first two steps. We introduce the analysis of an exemplary superstrate structure and investigate the optical properties of the single structure features. Preliminary results of this investigation are shown and a proposition of how to optimise the structure geometry is presented. [Copyright &y& Elsevier]

Abstract: Using ray track technology and geometrical analysis, this paper has presented novel design method which can be applied to mirror elements of equal width and varying width, varying height of absorbers of linear Fresnel Reflector Solar Concentrators(LFRSC) whose mirror elements are north-south direction. This paper also discussed the efficiency of mirror elements, it calculated the efficiency every 5°from 30°to 150°and the conclusions gave some parameters with reference value. [Copyright &y& Elsevier]

Abstract: This paper presents analysis studies of solar energy harvesting potential in Ulu Pauh, Perlis, Malaysia which located at 6.462°N, 100.351°E. Solar radiation is radiant energy received from the sun, from both direct and diffuse or reflected sunlight. In average of the year, Perlis able to receive about half day of solar radiation regardless the reflectivity. Perlis is northern state of Peninsular Malaysia and known as hottest state in Malaysia with the average 12hours of sunlight received per day. The discussion in this paper also includes several factor and parameter in the solar energy collecting potential analysis. The analysis studies had updated for last six month in year 2011. The potential of receiving solar radiation at 6.462°N, 100.351°E is compared to 6.431°N, 100.185°E with support by recorded data using Davis Vantage Pro2 Weather Station. All the data used in this paper are live record for the past six month which used for ongoing research on solar and wind energy. [Copyright &y& Elsevier]

Abstract: The present technology of the photovoltaic is still highly costing and the efficiency can improve to maximize efficiency, so the investor need to collect and study the return of project. In general the photovoltaic module has life time about 25 years and the almost of Photovoltaic Power Plant costing modules about 70% of portion. Hence, the degradation of photovoltaic module has an effect to the energy yield and benefit of project. The return of the project also depend on many factors such as the temperature, moisture content, the damaged of modules, government subsidy, CDM benefit and etc. This paper is considered the effecting about the degradation of 2.16MW amorphous photovoltaic power plant that the energy yield output is directly affect the capital and cost of project. The return of the investment when the solar module was degrade of the efficiency 10%, 20%, 30% by using NPV, BCR, IRR and PB to find out though the breakeven point of project and the degradation percentage that unacceptable to investment. This paper output applicability to determine to others amorphous photovoltaic power plant project by adjustment some information and factors appropriate to each project site. [Copyright &y& Elsevier]

This paper aims to investigate the possibility of integration of Electric Vehicles EVs supply's with electricity and/or hydrogen in the road transport sector and estimate the energy supply derived from solar irradiation by using solar roads technology. The case study is road Est-Oust (road E-O) of Algeria. A Geographic Information System and spatial analysis tools are combined with spatial data and technical models to carry out these calculations. The results of this study demonstrate that solar road panels, which are integrated into the road E-O, produce over to 804 GWh/year which equivalents to 13778 tons of hydrogen per year.by using FCEVs will saving over then 41.103 liter of fossil fuels (regular gasoline); and reduce GHG emission (CO 2) in the transportation sector by 216 tons per year. [ABSTRACT FROM AUTHOR]

Abstract Solar heating system has raised much attention due to the global energy shortage and environment pollution. The dynamic heat release performance of water tank (WT) with phase change materials (PCM) plays an important role in the operation of solar heating system, while seldom available literatures focused on this research topic. In this paper, an experimental system for heat release of the WT-PCM was established. The temperature variations of the water and the PCM during heat release of the WT-PCM and the traditional water tank were measured respectively, and their dynamic heat release performance were also analyzed based on the measured data. The results are as follows: the heat release of the WT-PCM can be divided into three phases: sensible heat before phase change, latent heat during phase change and sensible heat after phase change, and the water temperature will be temporarily heated after the sudden drop; the water supply temperature decline rate of both tanks will increase dramatically at the initial stage of heat release, when the PCM temperature is reduced to 50℃, the water supply decline rate of the WT-PCM is less than that of the traditional water tank, while when PCM is completely solidified, the water supply temperature decline rate of the WT-PCM is more than that of the traditional water tank. The heat release performance of the WT-PCM is much better than that of the traditional water tank. The research results can provide useful reference for engineering application of the WT-PCM. [ABSTRACT FROM AUTHOR]

Abstract In smart grid, smart meter (SM) samples users' energy consumption at high frequency. By analyzing the fine-grained smart metering data, users' behavior patterns can be recognized thus threatening consumers' privacy. In this paper, the protection of SM privacy is studied in the presence of solar energy generation system and a rechargeable battery (RB). Solar energy plays the role of an alternative electricity provider for users except power grid. RB can be used to partially hide the real appliance consumption while cut down the electricity bills. A "privacy safe-cost friendly optimal model" is developed aimed at minimizing the weighted sum of privacy leakage and financial cost, with constraints of battery physical conditions and solar radiation amount. In order to solve the optimal problem, we formulate a novel inner-outer optimal algorithm. Simulations demonstrate the efficacy of the proposed algorithm using real data. The impact of the battery capacity and the amount of solar energy on the privacy protection is also studied. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a thermoeconomic analysis of a solar combined heating and power (S-CHP) system based on hybrid photovoltaic-thermal (PV/T) collectors for the University Sport Centre (USC) of Bari, Italy. Hourly demand data for space heating, swimming pool heating, hot water and electricity provision as well as the local weather data are used as inputs to a transient model developed in TRNSYS. Economic performance is evaluated by considering the investment costs and the cost savings due to the reduced electricity and natural gas consumptions. The results show that 38.2% of the electricity demand can be satisfied by the PV/T S-CHP system based on an installation area of 4,000 m2. The coverage increases to 81.3% if the excess electricity is fed to the grid. In addition, the system can cover 23.7% of the space heating demand and 53.8% of the demand for the swimming pool and hot water heating. A comparison with an equivalent gas-fired internal combustion engine (ICE) CHP system shows that the PV/T system has a longer payback time, i.e., 11.6 years vs. 3 years, but significantly outperforms the ICE solution in terms of CO 2 emission reduction, i.e., 435 tons CO 2 /year vs. 164 tons CO 2 /year. These findings suggest that even though the economic competitiveness of the proposed PV/T S-CHP system is not yet favourable when compared to the alternative gas-fired ICE-based system, the S-CHP solution has an excellent decarbonisation potential, and that if this is of importance in the wider sense of energy-system decarbonisation, it is necessary to consider how the higher upfront costs can be addressed. [ABSTRACT FROM AUTHOR]

Abstract Achieving low energy consumption and maintaining proper day-lighting environment is a challenge for large atrium building under cooling-dominant climates. Fortunately, aerogel glazing system has recently been considered to have great potential in energy-saving applications for architectural glass due to its special light transmission and thermal insulation properties. In this paper, eight aerogel glazing samples were prepared by filling aerogel particles with four different diameters into hollow glass with two different thicknesses (viz., 5 mm and 7.5 mm). The thermal and optical parameters of the aerogel glazing were experimentally measured and the day-lighting performance was calculated. A case study of the aerogel glazing installing at different positions in a large atrium building under cooling-dominant climates was carried out. The results indicate that installing aerogel glazing at the skylight with is more effective than at the outside windows. The envelope heat gain was reduced by 31% by replacing the single glazing with the HA-type aerogel glazing at skylight under the condition of indoor illumination. [ABSTRACT FROM AUTHOR]

Abstract Adsorption desalination is an attractive and potentially competitive method of desalination among the conventional thermal desalination methods due to its ability to produce both freshwater and cooling effect. This desalination cum refrigeration system uses a low-grade heat from the solar collector to generate water vapor from the adsorber. The system employs a combined flash evaporation and thermal compression to produce potable water and cooling. In this paper, the operating and performance parameters of an adsorption desalination system has been studied. The analysis is based on the energy conservation principle applied to all processes of the theoretical cycle. The Dubinin-Astakhov model is used to describe the adsorption characteristics of the adsorbent-adsorbate pair (silica gel-water). The cycle is analyzed using the performance parameters such as fresh water production, energy consumption per kg of water produced and coefficient of performance. [ABSTRACT FROM AUTHOR]

Abstract This paper proposes a distributed solar-assisted biomass gasification power generation system based on internal combustion engine and analyzes the complementary properties of solar energy and biomass. The heat demand of biomass steam gasification is provided by solar energy, which reduces the consumption of biomass fuel, and then the product gas drives the internal combustion engine to generate electricity. Under the design conditions, the thermodynamic performances influenced by the two main parameters including power load and solar radiation intensity (DNI) are studied. The results show that the energy efficiency and exergy efficiency are 17.33% and 16.82% respectively. The increase in the share of solar energy leads to a reduction in energy efficiency and exergy efficiency, and the increase in the share of biomass is conducive to improving efficiency. [ABSTRACT FROM AUTHOR]

Abstract Based on the principle of "temperature counterpart and energy cascade utilization" a solar-hybird distributed system driven by natural gas is designed. In this paper, the thermal performance and environmental performance of the system are calculated. The results show that the thermal efficiency of gas turbine is significantly increased with the increase of heat collector area, and when the collector area reaches 1949m2 the thermal efficiency of the gas turbine run up to 44.43% and the fuel consumption reduce by 43.5%. Meanwhile, the introduction of solar subsystem makes the system's environmental performance greatly improved, and when the collector area reaches 1949m2, the CO 2 emission reduction reaches 257.5kg/h. The simulation results show that the supplementary way of solar energy and natural gas is an effective method in distributed energy systems. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, an overview of the production and consumption of Kuwait electrical energy, installed capacity and peak loads are presented. The results show that Kuwait has a serious situation because of the electrical energy lacking and load peaking. Based on the fact that Kuwait has enough budgets to transform all the power station powered by oil with renewable energy sources turning to greener Kuwait. The paper also is identifying and analyzing the geographical and temporal variability of solar energy inside Kuwait. The fundamental solar models are modified to estimate and identify daily and hourly solar radiation on horizontal surfaces on the basis of the more readily available meteorological data. The presented results prove that Kuwait has an abundance of solar energy capability in terms of almost cloudless atmosphere for nine months and twelve hours solar time a day over the year. The daily global and monthly averaged solar intensity on horizontal surface at Kuwait area is ranging from 3 Wh/m2 in winter to 8 kWh/m2 in summer. Monthly averaged clear sky solar radiation on horizontal surfaces at Kuwait area is ranging from 500W/m2/day to 1042W/m2/day. [Copyright &y& Elsevier]

Abstract: The production of electricity from solar radiation is a direct process. Solar energy is not very dense, it is necessary to concentrate it to produce exploitable temperatures usable for the production of electricity. The radiation may concentrate on a point or on a line, where thermal energy is transferred to the heat transfer fluid. The intensity of concentration is defined by the concentration factor, the more this one is higher, the more reached temperature will be important. In this paper two optical technologies which showed promising results were compared, the first one is the Fresnel mirror and the second one is the parabolic trough. These two technologies are based on linear solar concentration. The main objective of this paper is to report the performance of these technologies by means of numerical analysis. A methodological analysis to design and evaluate the technical feasibility for the use of Fresnel mirror or parabolic trough in a Concentrating Solar Power (CSP) system has been carried out. The influence of ambient conditions and the percent of different types of energy loss, etc., are analyzed. An application on a site, in the south of Algeria (Hassi Rmel), is done. In this site, a project of hybrid natural gas/solar power plant with parabolic trough technology will be inaugurated before 2011. [Copyright &y& Elsevier]

Abstract High rate electric vehicle chargers (HREVCs) are becoming an important part of transportation infrastructure. This is due to their ability to enable journey distances which are longer than the range of the electric vehicle (EV). Often, HREVCs need a high power grid connection which can be very expensive, or impossible. HREVCs which are powered by co-located renewable energy are an effective way of reducing the necessary grid capacity for installation when used with an Off-vehicle energy store (OVES). The control strategy for charging this OVES from the grid is addressed in this paper by comparing static and dynamic charging powers. It was found that the dynamic charge pattern reduced both imports and exports to the HREVC over one year over the static grid charge case. Thereby showing that using the dynamic charge strategy enables HREVCs to be installed on a smaller grid connection and use less grid power. [ABSTRACT FROM AUTHOR]

Abstract In this paper the performance of a solar heating network devoted to satisfying the heating demand of a micro-scale district composed of 6 typical single-family houses and 3 typical schools under the climatic conditions of Naples (south of Italy) is investigated by means of the dynamic simulation software TRNSYS over a 5-year period. The proposed system is composed of a solar collectors array, a short-term thermal energy storage, a long-term double U-pipe vertical borehole thermal energy storage and a heat distribution network. Three different technologies are investigated as back-up devices to be included in the district heating system: (i) a natural gas-fired boiler, (ii) a vapor-compression electric heat pump and (iii) a natural gas-fuelled internal combustion engine-based micro-cogeneration unit. The simulation results are compared with those associated to a conventional heating system in terms of primary energy consumption, operating costs as well as simple pay-back period in order to identify the best option in terms of back-up system and assess the potential energy and economic benefits associated to each technology. [ABSTRACT FROM AUTHOR]

Abstract A first of its kind concentrated solar power (CSP) installation has been integrated together with a biomass heat and power (CHP) plant using an organic rankine cycle (ORC) unit. The plant has been deployed in the northern part of Jutland in Denmark, right next to the city of Brønderslev. The plant has been supplying heat to the local district heating network since the end of 2016. Aalborg CSP has developed and built the CSP plant consisting of parabolic trough collectors with an aperture reflecting area of 26,920 m2. The CSP plant is able to deliver 16.6 MWth at its peak while it can supply the district heating or the ORC with approximately 16,000 MWh of heat annually. This paper serves as a description of the technical aspects of the system with specific focus on the CSP field as well as present the first measured performance from the Summer of 2017. [ABSTRACT FROM AUTHOR]

Abstract The use of solar energy for industrial purpose at medium-low temperature is receiving attention. As a matter of fact, this temperature range, usually between 80-200°C, requires low cost devices to convert solar energy into useful heat. In particular, the use of CPCs collectors has been suggested in literature because they can be operated without the use of a tracking system, at least within certain limits. The thermal losses of these devices are often reduced by using an evacuated pipe, but this solution increases the manufacturing costs and reduces the reliability and the optical efficiency of the receiver. A series of alternative methods for the thermal losses reduction has been proposed in this paper, for working temperature up to 200°C. Their effectiveness was evaluated by means of a previously validated CFD model. A cylindrical receiver and a concentration ratio of 2 were taken into account. The results were analyzed in terms of temperature contours and thermal efficiency. In particular, the optical efficiency was focused as a key parameter in the performances of a CPC. As conclusion, it was found that a proper arrangement of the absorber with a baffle may entail an improvement of the thermal efficiency without significantly increasing the complexity of the system. [ABSTRACT FROM AUTHOR]

Abstract Concentrated Solar Power technologies represent an important alternative able to replace in a medium/long term fossil fuel sources. Current technology has several drawbacks which prevent a large diffusion: the principal one is the choice of the Heat Transfer Fluid which involves a certain complexity, including the heat storage section. Conventional plants in operation, consider diathermic oil and, more recently, molten salts. The potential of gases as working fluid has been underestimated till now and its use has not still fully exploited. Using gas would determinate a simpler conversion section increasing reliability. The gas, as proposed by the authors, can expand directly in a series of inter-reheated turbines after a series of intercooled compressions, reaching an acceptable overall global efficiency of the conversion section. The paper describes the optimum choice for the thermodynamic cycle which approaches an Ericsson cycle, integrating it with a comprehensive mathematical model for the heating section of the gas inside the solar receiver. A Thermal Energy Storage section based on the use of a packed bed of rocks has been considered, merged at the plant to insure production continuity. The overall software platform for the plant can be used as design tool in order to set up most important alternatives related to the plant characteristics and specific parameters. [ABSTRACT FROM AUTHOR]

Abstract In a solar PV power plant, the plant availability factor is one of the important factors to be evaluated. This depends on the operative functioning of various components and grid regulation. In this paper, a simple method is proposed to evaluate the availability factors of a solar PV plant by considering the real time data of 1 MWp solar power plant that was commissioned in 2011 in south India. Generation start time, end time, and actual running periods of the inverter were selected as prominent data in the study. A consecutive five financial years of data (2011–2012; 2012–2013; 2013–2014; 2014–2015; 2015–2016) was used to observe the variations in availability factors of inverters, as well as the plant availability factors. From the analysis, it is observed that tripping time greatly effects the availability factor of inverter as well as the PV plant. The variation in availability factor over the five consecutive financial years is seen to be within the range of 92.44 % to 95.69 %. This clearly states that, on average 4.31 % to 7.56 %, the installed solar PV power is technically not generated any power. Hence, estimating the availability factor could be very much essential to deal with the performance of the PV systems and possible options of reducing energy losses due to availability factors could be suggested. [ABSTRACT FROM AUTHOR]

Residential buildings with limited natural lighting are generally lit by fuel-based electricity which contributes to increase of CO2 concentration in the atmosphere. This paper presents the design of a hybrid fiber-optic daylighting and PV solar lighting system for household applications. The system is composed of a light collecting subsystem, a light guiding subsystem, an optical fiber light diffuser subsystem and corresponding control system. Preliminary system performance shows that, the developed system could provide comfortable and natural indoor illumination. Meanwhile, the hybrid lighting system can provide an average of 9h of electric lighting under clear sky conditions, and reduce 158.2kg of carbon dioxide emission in a year within the tested dark room of 5m2. [ABSTRACT FROM AUTHOR]

In this paper, the design of a curved Fresnel lens applying to the concentrator photovoltaic system is proposed by using the edge ray theorem, the Snell’s law, and the conservation of optical path length. The new structure of the curved Fresnel lens can improve significantly the uniformity of sunlight distribution over the solar cell while the concentration ratio can reach a high value of 900 times. The good uniform distribution can be obtained by using the novel idea. The novel idea is based on the uniform sunlight distribution of every groove of the lens so that the whole lens also distributes uniformly the sunlight beam over the receiver. The structure of the lens is built by two surfaces: input surface (or upper surface) as a part of spherical surface and output surface (or lower surface) that consists all grooves of the lens. Matlab program is used to design the input and the output surfaces of the lens. The input surface and the output surface are independent to each other in construction in Matlab. Lighttools TM software is used to optimize the structure of the novel lens. Furthermore, Lighttools TM is also used to perform a simulation to examine the efficiency of the lens in concentrator photovoltaic (CPV) system by using the light source with a wide spectrum of 380 – 1600 nm. The results show that the lens has an acceptance angle of 0.8 0 and good optical efficiency (>85%). [ABSTRACT FROM AUTHOR]

Singapore's National Climate Change Policy is aimed to make energy usage in Singapore more efficient, reduce pollution and expand the nation's green spaces. Part of the plan is to promote the integration of solar photovoltaics (PVs) on rooftops of high-rise HDB residential and commercial buildings. This initiative contributed to the significant growth in the integration of solar PV systems in the last few years. However, large-scale integration of solar PVs will put at risk the reliability and stability of Singapore's power system due to its intermittent nature. The intermittency problem of solar PV, typically in the range of minutes, will become very significant in Singapore as the installations of PV systems continue to increase. Conventionally, large energy storage systems are deployed as an energy buffer to compensate for the deficit or surplus of power supplied by solar PV systems. However, the high capital and maintenance costs as well as large space requirement for energy storage systems makes this an unfavorable option for building owners. This paper proposes a solution that utilizes the centrifugal fans in building air conditioning and mechanical ventilation (ACMV) system to dynamically compensate for the deficit or surplus of power supplied by solar PVs. For example, the developed solution will reduce the load demand of fans in the ACMV system equal to the drop of solar generation by controlling the speed of the fan. This will ensure that the amount of power supplied by the grid to the building will remain the same (as before the drop of solar generation) and thus no impact on the grid stability. However, since ACMV system is directly linked to building occupant comfort/health, the proposed solution will also include battery management and priority-based load shedding programs to provide support when room temperature (air conditioning) or CO level (ventilation) is above regulatory limit. [ABSTRACT FROM AUTHOR]

Energy crisis is one of the most crucial topics in today's world. Conventional energy resources are not only limited and costly, but also the prime cause for environmental pollution. The environmental pollution and rising cost of the fossil fuels have drawn considerable attention to renewable energy sources. Solar energy, being the cleanest and most reliable renewable energy source, is widely utilized in thermal systems to heat water and air. It offers a vast opportunity for public and private organizations to reduce carbon emissions and cut electricity costs. A viable approach to maximizing the solar panel efficiency is solar tracking. This paper, therefore, proposes an automatic microcontroller-based solar tracker with a hybrid algorithm for locating the sun's position. The proposed hybrid solar tracking algorithm combines both sensors and mathematical models to determine the precise sun's position, thereby harnessing optimal solar energy for all weather conditions. Experimental results consistently show that the hybrid solar tracking algorithm can yield higher solar power that the traditional active and chronological algorithms. A webpage was also developed to facilitate real-time monitoring of solar data. As such, the solar tracking process is fully automated, maximizing the collection and management of solar energy for solar thermal systems. [ABSTRACT FROM AUTHOR]

Cassava is one of the most important cash crop in Guangxi Autonomous Region. The water demanded regulation of cassava is not coincident with the temporal and spatial distribution of precipitation. Irrigation is quite necessary for the growth of Cassava. Solar water pumping system is an effective way for Cassava irrigation. In this paper, the temporal and spatial distribution of Cassava is analyzed first. The potential and distribution of solar energy is also discussed. Considering the main factors including precipitation and slope to analyze the feasibility of solar water pumping system for Cassava irrigation. The results indicate that the Cassava appropriated for solar water pumping cover718 thousand and 500 hectares. The best matching region covers in 623 thousand hectares. [ABSTRACT FROM AUTHOR]

Solar powered irrigation technologies have developed significantly in the past decade assisted by the development of higher efficiency, low cost solar Photovoltaic (PV) panels. The technology has come so far as to be able to elapse diesel powered irrigation systems in terms of the payback period and reduction in greenhouse gasses. However, PV technologies are still not being used extensively due to their high initial investment costs and compared to other renewable energy technologies the carbon footprint is still comparatively large. On the other hand, solar thermal technologies are seen to be much cheaper, and have a much smaller carbon footprint, but are marred by low efficiencies. This paper investigates solar powered irrigation technologies (PV and solar thermal technologies) that can be utilised by independent farmers in small-scale remote rural farms in Sub-Saharan Africa. The focus is to be able to identify affordable solar powered irrigation systems that will make use of local resources effectively for drip irrigation. [ABSTRACT FROM AUTHOR]

This paper put forward a new method that using the perovskite–type oxide (LaCu x Ni 1-x O 3 ) as the solar thermal energy storage material which can drop the reduction temperature to below 500℃ that parabolic-trough solar collectors could reach. Herein, LaCu x Ni 1-x O 3 (x =0, 0.1, 0.2, 0.3, 0.5) is synthesized and investigated. Besides, the physical and chemical properties of LaCu x Ni 1-x O 3 are tested by XRD, SEM and BET, and the reactivity and generation are studied through experiments by means of thermogravimetric analyzer (TGA). Experimental results indicate that these five oxygen carriers are of high porosity and this porous structure benefits from doping by Cu at B-site when LaCu x Ni 1-x O 3 reacts with methane at 350℃, it exhibits great performance such as high reproducibility and good resistance for carbon formation. No obvious sintering is appeared after 30 times multiple redox cycles and LaCu 0.1 Ni 0.9 O 3 is able to be reoxidized to initial oxidation state. [ABSTRACT FROM AUTHOR]