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A Dynamic Bayesian network (DBN) model for solar power generation forecasting in photovoltaic (PV) solar plants is proposed in this paper. The key idea is to fuse sensor data, operational indicators, meteorological data, lagged output power information, and model errors for more accurate short-term (e.g., hours) and mid-term (e.g., days to weeks) power generation forecasting. The proposed DBN augments automated data-driven structure learning with expert knowledge encoding using continuous and categorical data given constraints to represent causal relationships within a solar inverter system. In addition, an error compensation mechanism that uses an error node to capture the temporal fluctuation caused by system degradation or failures is proposed to capture temporal fluctuation. The effectiveness of the DBN on solar power generation forecasting was evaluated by rolling window analysis with one-year testing data collected from a local solar plant. The proposed DBN is compared with four state-of-art methods including support-vector regression (SVR), k-nearest neighbors (kNN), artificial neural network (ANN), and long short-term memory (LSTM) models. The results show that the proposed DBN achieves better accuracy in general, and it is not as data-hungry as some neural network-based models. The proposed DBN is also shown to have robust and consistent forecasting power with different forecasting horizons. The accuracy is 92 %–95 % from 1 h to one week ahead forecasting. • A Dynamic Bayesian Network (DBN) with multi-source information fusion is proposed. • Automated data-driven structure learning is augmented with expert knowledge. • Error compensation mechanism increases forecasting accuracy. • Proposed DBN outperforms other state-of-the-art methods with fewer data. • Proposed DBN delivers multi-horizon solar power generation forecasts. [ABSTRACT FROM AUTHOR]

As countries worldwide seek to reach net zero emissions within the coming decades, data center sustainability measures are becoming increasingly important as these facilities consume substantial amounts of electricity to support globally expanding digital infrastructure. Yet, local renewable energy production and waste heat utilization are still rarely used in data centers, even though recent high electricity prices have considerably increased the economic value of self-generation and energy efficiency investments. The benefits and cost-effectiveness of data center sustainability measures have also not yet been thoroughly researched in cold-climate regions, where the data center industry is currently growing rapidly. Thus, this paper assesses how solar photovoltaics (PV) and waste heat utilization can effectively be integrated into different cold climate data centers, with a case study analyzing data centers in Finland and northern Japan. The modelled results indicate that solar PV systems can cost-effectively be used to provide renewable electricity to data centers in both Finland and northern Japan, with electricity prices having the largest influence on economic performance. The use of larger external PV systems is shown to be cost-effective at the higher electricity prices seen in 2022, whereas smaller rooftop PV systems and grid electricity provide more economic benefits at 2019 price levels. Selling surplus PV electricity to the grid and using waste heat for district heating is also shown to be effective in data centers located in Finland, whereas battery storage and snow melting are better suited to utilize surplus PV electricity and data center waste heat in northern Japan. [Display omitted] • Solar photovoltaic systems can cost-effectively reduce data center emissions in cold climate countries. • Data center waste heat can provide value in district heating and snow melting applications. • The cost-effectiveness of data center sustainability measures is largely influenced by electricity prices. • The option to sell surplus electricity to the grid incentives larger solar photovoltaic investments in data centers. [ABSTRACT FROM AUTHOR]

As subsidies continue to fall, the technology and cost performance of distributed photovoltaic (PV) determines the progress of its grid parity. Based on the discussion of technology and cost, this paper analyzed the economic performance of China's distributed PV industry by utilizing the two indicators of levelized cost of energy (LCOE) and internal rate of return (IRR). The results show that: firstly, the current external environment is generally conducive to the development of distributed PV, but there are still some constraints. Secondly, with the decrease of unit investment cost, distributed PV can achieve the goal of parity before 2025. Thirdly, distributed PV projects in the three types of solar energy resources all have high IRR, and the economic performance is better for the projects with high proportion of spontaneous self-use. At the end of the paper, policy recommendations are offered as references for the government. • We comprehensively analyzed the technology and cost performance of China's distributed PV. • We focused on the trend and decline path of China's distributed PV costs. • The LCOE of distributed PV in China is expected to achieve full parity in 2025. • Except 100% grid-connected mode, the IRR of distributed PV power plants in three areas is higher than 8% which has shown good economic benefits. [ABSTRACT FROM AUTHOR]

Mismatch losses ignore the performance of individual photovoltaic (PV) modules and cut back most of the power from the PV array. These losses mainly due to partial shading condition (PSC), are caused by the reduction of spacing between PV modules, passing clouds, and near buildings, etc. Several techniques are present in the literature to cut back the partial shading issues. One of the most effective methods is the reconfiguration techniques, namely reconfigure the location of PV modules in PV array so as to distribute partial shading effects and increase the maximum power output. This paper proposes an Improved SuDoKu reconfiguration pattern for 9 × 9 Total-Cross-Tied (TCT) PV array to enhance maximum power output under partial shading conditions. The main aim of this approach is to arrange the PV modules in TCT array according to the SuDoKu pattern without altering the electrical connections. Further, the performance of the proposed pattern is evaluated with different existing PV array configurations by comparing the Global Maximum Power Point (GMPP), Mismatch Losses (ML), Fill Factor (FF) and Efficiency (η). Based on the results of this paper, it is concluded that the proposed improved SuDoKu PV array arrangement enhances the global maximum power under all shading conditions. • This paper proposed an Improved SuDoKu arrangement for 9×9 Total-Cross-Tied PV array to enhance Maximum power under PSCs. • Performance of the proposed arrangement is evaluated with existing PV array configurations. • The proposed arrangement is increasing the maximum power and reducing the mismatch losses as compared to other configurations. [ABSTRACT FROM AUTHOR]

As the development of distributed solar photovoltaics (DSPV), battery energy storage systems are growing in popularity to promote the performance of DSPV, for both mitigating the impact on the grid and increasing the economic performance. In the meantime, reused batteries retired from electric vehicles provide another option for energy storage systems. In this paper, the economic performance evaluated by net present value of DSPV with reused batteries as energy storage systems (RBESS) is studied at the provincial level in China, so as to depict a comprehensive understanding of the current DSPV status and the development potential of RBESS in China. Instead of only focusing on the role of increasing the percentage of self-consumption (Model 1), a combined usage strategy of RBESS (Model 2) is also proposed. Moreover, the residual value of lithium-ion batteries is taken into consideration in this paper. Our results show that for the residential sector, only a small number of areas can benefit from RBESS under Model 2, while none can benefit under Model 1. Only when the price of RBESS decreases to 200 CNY/kWh, the profitability could be nationwide. However, for the commercial and industrial sector, the performance of RBESS is much better. In the majority of areas, integrating RBESS with DSPV is already profitable. • Provincial level analysis is conducted. • Two using strategies of RBESS are presented. • Only when the price of RBESS decreases to 200CNY/kWh, can the positive NPV be nationwide. • The C&I sector outperforms the residential sector in terms of the ability to gain profits from DSPV and RBESS. [ABSTRACT FROM AUTHOR]

Abstract Under the circumstances of global carbon emissions reduction, it has become a trend to promote the adoption of clean energies, such as solar energy. With the increasing maturity of photovoltaic (PV) technology, household-type distributed solar PV power generation projects are increasingly popular in China. Nevertheless, compared with conventional power generation, the initial cost of a solar PV project remains relatively high. Therefore, to mobilize the incentives of the general public, there is an urgent need for studies on how to share the costs and benefits of a solar PV power generation project between the government and users. By adopting the Shapley Game methodology, this paper has conducted a theoretical analysis of the cost-sharing among the central government, local government, and users and has built an investment cost-sharing model ( C i ′ = P (i) − V s (i) − V r i , i = 1 , 2 , 3) , which is able to coordinate the benefit of all three stakeholders. This is followed by a case study. The results show that, under China's central government subsidy of 0.42 yuan per kWh, the best strategy for the local government to encourage the public to install solar PV facilities is to provide a one-off compensation equal to 30% of the initial investment. Finally, this paper proposes relevant policy recommendations to promote the development of solar PV power generation for emissions reduction in China. Highlights • We made a cost-sharing analysis of a solar PV project using the Shapley value. • We built an investment cost-sharing model (C′i = P(i)- Vs(i)- Vri, i = 1,2,3). • Providing 30% of initial subsidy is the best strategy for China's local government. [ABSTRACT FROM AUTHOR]

Photovoltaic Poverty Alleviation (PVPA) projects, which utilize the subsidies and income from PV power to alleviate poverty in rural areas, are part of a comprehensive energy policy innovation in China. It is expected that the projects will deploy at least 10 GW PV and benefit more than two million poor households in total by 2020. To achieve this goal, specific supporting policies and novel business models are necessary. In the present paper, the current status and existing supporting policies are introduced to give an overview of PVPA projects. Then representative business models in PV projects are summarized and compared to provide a reference for PVPA projects. Obstacles, such as subsidy delays, insufficient infrastructure, low quality of PV equipment, and inflexible profit allocation mechanism may reduce the revenue from PV operation and increase the costs of PV deployment. Therefore, this paper also proposes corresponding recommendations for policy makers considering the existing challenges. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze the economic and environmental aspects of installing PV facilities for residential electricity users. This paper explores, in a conservative approach, the installation of a PV capacity to compensate the consumption with the production for each moment, never feeding electricity into the utility network and without storage. The approach proposed is illustrated by applying different power PV capacities in alternative locations (Marseille, Madrid and Seville), using the hourly demand provided for the smart meters. Combining the load curve of each user, the irradiation and PV production of each location, the cost of equipments, the hourly emission in the whole market, the variable price of electricity for residential users and the energy needs to build a PV facility. The model calculates, for each individual the optimal PV power to install and the emissions avoided. The results show that, with the current cost of the PV facilities and variable prices of electricity, the PV are, from an economic and environmental point of view, profitable in all the locations analyzed. This initiative will be more profitable for private investors and, additionally, for the environment in the next three years. A massive installation of these facilities in Spain and France will contribute to achieving their Nationally Determined Contribution (NDC) of the Paris agreement (COP-21), fulfilling, in Spain, the current legal restrictions. [ABSTRACT FROM AUTHOR]

This paper presents the development of methods and mathematical models to determine the DC/AC average efficiency of inverters that allow to optimize estimates of electricity generation of photovoltaic systems. The adaptive hybrid mathematical model of DC/AC average efficiency of inverters of photovoltaic systems proposed in this paper may be composed of three function settings–Linear, Lognormal, and Polynomial–considering the influence of the relative power, which varies with the sizing factor inverter and the DC input voltage. Determining of the average efficiency with a high degree of accuracy guarantees greater reliability in estimating electricity generation of photovoltaic systems. Depending on the specific behavior of each model and topology of inverter, the adaptive hybrid mathematical model determines the fit functions with highest coefficient R 2 , and estimates with accuracy the DC/AC average efficiency that represents the operation and dynamic behavior of the inverters. [ABSTRACT FROM AUTHOR]

Electrical energy becomes necessary for human being. Generation of electrical energy mostly depends on fossils fuel, they are limited in nature and also responsible for environmental pollution. Renewable energy resources provides a better alternative for future,In comparison to conventional energy resources economical aspect is a major issue of renewable energy sources with the feasibility and efficiency. These limitations are tried to overcome by deployment hybrid renewable energy resources. There are certain criteria to analyze and implement the sized, optimized and cost efficient system. This paper focus on hybrid energy systems based on solar photovoltaic (PV) and wind resources. This paper shed lights on various parameters of economic feasibility, sizing strategies with logical advancements to enhance their utilization, future prospects, and their arrangement. Strategies to develop an effective storage system is also presented here.A brief review on developments in optimization techniques, reliability index and cost analyzing techniques for hybrid renewable energy systems are also presented. [ABSTRACT FROM AUTHOR]

Photovoltaics (PV) and electric vehicles (EVs) are promising technologies for increasing energy efficiency and the share of renewable energy sources in power and transport systems. As regards the deployment, use and system integration of these technologies, spatio-temporal modeling of PV power production and EV charging is of importance for several purposes such as urban planning and power grid design and operation. There is an abundance of studies and reviews on modeling of PV power production and EV charging available in the literature. However, there is a lack of studies that review the opportunities for combined modeling of the power consumption and production associated with these technologies. This paper aims to fill this research gap by presenting a review of previous research regarding modeling of spatio-temporal PV power production and charging load of EVs. The paper provides a summary of previous work in both fields and the combination of the fields. Finally, research gaps that need to be further explored are identified. This survey revealed some research gaps that need to be further addressed. Improving the accuracy of PV power production ramp-rate modeling in addition to quantifying the aggregate clear-sky index on city-scale are two priorities for the PV potential studies. For the EV charging load models, differences in model assumptions, such as charging locations, charging powers and charging profiles, need to be studied more extensively. Moreover, there is an imminent need for metering the load of charging stations. This is essential in developing accurate models and time series forecasting techniques. For studies exploring both the PV and EV impacts, local weak points in a spatial network need to be discovered, especially for the city-scale studies. Cooperation between eminent researchers in the PV and EV fields might propagate state-of-the-art models from the separate fields to the combined studies. [ABSTRACT FROM AUTHOR]

Photovoltaic system is widely installed to increase the share of renewable energy as well as to reduce the environmental impact of fossil fuel based energy. Photovoltaic (PV) is one of the most potential renewable energy based power generation systems. Monitoring of PV system is very important to send information that allows owners to maintain, operate and control these systems to reduce maintenance costs and to avoid unwanted electric power disruptions. Different monitoring systems have been introduced with the time following different requirements. Circuit complexity, availability of friendly graphical user interface, easy to understand system architecture, maintenance facility and customization ability for end user differ from system to system along with cost issues. This paper provides an overview of architectures and features of various PV monitoring systems based on different methods. There are various technologies for PV monitoring and control, developed as for commercial use or research tasks. It has been seen that a large portion of the work is done on classifications, for example, Internet based Monitoring using Servers, TCP/IP, GPRS and so forth. There are various methodologies for data acquisition, for example, PLC (Power Line Communication), PIC, Reference cell, National Instruments etc. Various requirements are considered while selecting a proper monitoring system for an application. Review of various monitoring technologies with system attributes and working structures have been discussed to get a clear view of merits and demerits of existing PV monitoring systems. All the systems discussed in this paper have pros and cons, and these systems were developed following different requirements. In the end, a particular cost effective monitoring system using Arduino microcontroller has been proposed considering both research and user level requirements from perspectives of cost, availability of parts/modules and features, compatibility with sensors and end-devices etc. [ABSTRACT FROM AUTHOR]

Photovoltaic panels are semiconductor materials having electrical efficiency in between 4% and 46% depending upon its material. About 50% of total solar radiation absorb by photovoltaic panel convert into heat causing high operating temperature of photovoltaic panel (PV) results to drop in its electrical performance and permanent structural damages called thermal degradation if a thermal stress remains in PV panel for long. So cooling of photovoltaic panel is very essential for better performance and long life of photovoltaic module. Many researchers have investigated performance of photovoltaic module by using different cooling arrangements having different thermal absorber design, different coolants and different phase change materials (PCMs). Detailed review of various methods related to water based photovoltaic/thermal system (PV/T) and photovoltaic panel with phase change material (PV-PCM) system has been discussed and reported in this paper. This review paper can help to find new cooling arrangements, different thermal absorber design and different phase change materials for improving performance of photovoltaic/thermal system. It has been observed from the literature that photovoltaic panel with phase change material (PV-PCM) is proficient solution for cooling of photovoltaic panel. But problems associated with phase change material are its low thermal conductivity and nocturnal solidification which affect its readiness and thermal drop performance for same day and next day therefore, performance of photovoltaic panel with phase change material (PV-PCM) system can be enhanced by inserting heat transfer elements within PCM and extracting heat from PCM to regulate temperature of phase change material to maintain its heating storage capacity. Extracted heat from PCM can be use for space heating or water heating applications. [ABSTRACT FROM AUTHOR]

In recent years, continuous depletion of conventional energy resources and the fluctuating fuel cost have motivated research on alternative source for power generation. To effectively harvest power from the green energy resources, extensive research have been carried out in literature. Solar energy being the foremost among all other renewable energy resources has evolved as a reliable substitute for the conventional power generation. Unlike other sources, real time research on Photovoltaic (PV) Systems is a difficult assignment as it necessitates an accurate PV emulator that can precisely replicate the nonlinear characteristics of a PV cell. PV Researchers have developed emulators of different type utilizing various configurations. This paper attempts to present a comprehensive review on different PV emulator topologies so as to gather all the research activities that are scattered in this arena under a common umbrella. Further this paper provides a detailed analysis of each technique emphasizing on its (i) Realization cost (ii) Accuracy (iii) Level of complexity (iv) Sensitiveness to varying environmental conditions (v) Hardware implementation and (vi) Efficiency. [ABSTRACT FROM AUTHOR]

In order to meet global sustainability goals, in particular, the rapid decarbonisation of the energy sector in combination with geopolitical energy security issues, as well as further improvement in regional air quality-the so-called renewable energy sources are becoming increasingly critical and important. Photovoltaic power (PV) generation is clearly the most widely deployed (non-hydro) renewable energy source globally, which still has a significant growth potential in many countries, including Hungary. However, due to the intermittent nature and the strong dependency of photovoltaic power production on meteorological factors, continuous adjustment of electric power in the electric grid is needed. This, in turn, requires the most accurate forecast of the photovoltaic energy to be produced in the ultra-short term (15 min) and short term (1 day) in order to minimise last-minute and high-price energy acquisition or unplanned kicks-in of gas-fired auxiliary power plants. In this paper, we evaluate the impacts of large-scale dust transport episodes on the accuracy of forecasts of PV power generation. The numbers and intensities of Saharan dust storm events reaching Central Europe have increased over the last decade, hitting a new record in 2022 with 16 (!) African dust episodes observed over Hungary. We have shown that the semi-direct effect of atmospheric dust particles on high-level cloud formation rather than their direct irradiance-reducing effect is responsible for the reduced accuracies of e short-term (24-h) PV energy production forecasts during these events. • 16 Saharan dust events (SDEs) were identified in Hungary in 2022. • SDEs caused photovoltaic (PV) generation drops and forecast errors. • Indirect effect of dust on irradiance (through cloud formation) was the dominant. [ABSTRACT FROM AUTHOR]

Solar photovoltaic (PV) systems have the greatest potential to meet the scale of sustainable energy demands, yet large surface areas beyond rooftop areas are required. One source of additional surface area that avoids conflict with food production while scaling with population density is noise barriers, which provide dual use of land area both as noise abatement and energy generation. This paper provides a method to quantify the potential of mass scale deployment of photovoltaic noise barrier (PVNB) systems in a country. Based on a feasibility analysis of the irradiation levels and noise barrier locations, the PV power potential and the energy output for the photovoltaic modules is calculated for specific locations using a tool chain of free GIS software. This method, is then demonstrated with a case study for the state of California and the results are then extrapolated for the entire U.S. The U.S. is an ideal candidate country because noise abatement mandates fall well short of World Health Organizations guidelines and PVNB technology has not been implemented on a wide scale. Using conservative assumptions, the results show that the total PVNB power potential for the U.S. ranges from 7 to 9 GW using only existing noise barriers. According to findings of the paper the installed capacity of the large scale photovoltaic system deployed on noise barriers in a single state is comparable to the installed capacities of the largest solar farms in the U.S. and yet due to the unique mounting of PVNB, such systems provide better land utilization ratios for energy production than conventional solar PV farms. [ABSTRACT FROM AUTHOR]

Electricity is the fastest-growing final form of energy. The strong growth of renewable in many countries raises their share in global power generation to one-third by 2040 [1] . Lack of access to electricity is one of the biggest troubles facing the world's poor, with over 1.6 billion left in the dark globally. The substantial majority of human beings live in rural areas of developing countries which is too far away to be reached through the national grid. For their lighting needs they depend on candles, kerosene lanterns, and firewood* This consequence in an each day rate that is high priced in the long run. Long-term, solar energy is the most practical and low-budget way of bringing power to far flung communities. Small-scale, distributed solar home systems provide an effective and affordable way to bring light to people without electricity. Egypt's electricity use has been growing swiftly as a end result of economic growth in the closing decade. However, Egypt has a massive of its populace residing in rural areas access to energy is still a challenge. The power sector is key to Egypt's monetary development and poverty decrease goals. This paper represents support sustainable livelihoods for rural communities. The paper refers to renewable energy for rural populations with no access to centralized electricity power. The focus is on solar electrical energy and its economic applications for village electrification. The Paper goals to compare between electrical energy cost (kWh) using PV panels, diesel generator and the end of result suggests the cost of 1 kWh from the PV system is less than diesel system for rural residential electricity are 0.22$/kWh and 0.5$/kWh respectively. [ABSTRACT FROM AUTHOR]

The classical algorithms for maximum power point tracking ensure proper operation under uniform irradiance conditions. However, when photovoltaic (PV) array is subject to partial shading conditions (PSC), several local maxima appear on the P-V characteristics curve of the PV array which are due to the use of the bypass diodes to avoid hot spots effect. The appearance of these multiple peaks on the characteristics of PV array makes the tracking more difficult under these conditions and requires the integration of a more efficient power control system which is able to discriminate between local and global maxima to harvest the maximum possible energy and therefore increase the efficiency of overall system. In addition to implementing a global maximum power point tracking strategies, the mismatch losses associated to the shading effect can further be reduced by using alternative PV arrays’ configurations such as Total-Cross-Tied (TCT), Bridge Linked (BL) and Honey-Comb (HC). For this purpose, the main aim of this paper is to design an intelligent MPPT controller that allows predicting and extracting the global maximum power point (GMPP) from PV array under partial shading conditions (PSC) whatever is the used configuration or its size. This intelligent MPPT controller is based on adaptive neuro-fuzzy inference system (ANFIS). The adopted ANFIS network has two inputs and one output. The two inputs of the proposed ANFIS consist of voltage and current while, the output is the output power of each configuration. The ANFIS network is trained using the data derived from performances analysis of different PV array configurations. Furthermore, the ANFIS network uses a hybrid learning algorithm that combines the least-squares estimator and the gradient method. The Bishop model of a PV module which describes best the solar cell behavior at negative voltages is considered in this paper for modeling the PV arrays, and it is implemented by using the Simulink and SimPower software. The effectiveness of the proposed method is investigated for TCT configuration under partial shading conditions for various shading scenarios and sudden irradiance change. The results show that the proposed algorithm can track the global MPP effectively and is robust to various shading patterns. Simulation results show high tracking performances in terms of efficiency, tracking speed and system stability. The results are also presented for different configurations such as HC, BL and Series-Parallel (SP) to show the ability of the proposed technique to detect the right peak regardless of the used configuration. [ABSTRACT FROM AUTHOR]

This paper provides useful insights regarding the financial implications of the currently applied Net Energy Metering (NEM) practice in Cyprus through analyzing the implemented policy under: a) the customers’ perspective and b) the utility (Electricity Authority of Cyprus) perspective. These two perspectives are known in the scientific literature as the participant cost test and the utility cost test respectively. Within the paper, the financial analysis from the customers’ perspective, it embraces the impact resulting from a series of factors influencing the viability of net-metered PV systems’ investments. Furthermore, the analysis from the utility's perspective relates to the expected costs and benefits that EAC may experience due to the current NEM rules and applied charges. Finally, the key findings pertaining to the current NEM policy's hidden financial and policy implications are critically discussed. This discussion is performed to facilitate a more diligent NEM policy that will allow further penetration of roof-top PV systems through well-informed and transparent decisions. [ABSTRACT FROM AUTHOR]

Costly and eco-destructive diesel based systems are usually used for electrifying rural areas in Malaysia. Fuel transportation is another obstacle in this regard. Moreover, unpredictable fluctuation of fuel price makes the system cost unstable. The diesel based systems can be replaced with renewable energy (RE) based systems. Thus, a feasibility analysis is necessary to assess the potentiality of RE resources. This paper analyzes the potentiality of renewable energy in Sarawak, East Malaysia. The wind speed is insufficient, but solar energy is abundant at the location. Hence, the feasibility of photovoltaic (PV), Battery and Fuel Cell (FC) based systems are investigated for the load of a village longhouse comprising 50 families located in Kapit, Sarawak. Both systems, including FC (PV/Battery/FC) and excluding FC (PV/Battery) are analyzed and compared with conventional diesel based system. The analysis focuses on net present cost (NPC) and cost of energy (COE). Other cost parameters such as installation cost, operation and maintenance cost (O&M), operating cost are also analyzed. HOMER software provided by National Renewable Energy Laboratory (NERL) is used as an analyzing tool. This paper also focuses on the operational strategy and sensitivity analysis of the hybrid system for optimal performance. The HOMER optimization results and sensitivity analysis show that the PV/Battery system is economical and environmentally friendly with total net present cost of $ 335,297 and cost of energy of 0.323 $/kWh with no emission. Thus it can be a suitable replacement of diesel based system. The FC based system has higher costs; thus despite of its benefits, it is not suggested as the best system for the situation. [ABSTRACT FROM AUTHOR]

This paper first presents an overview on traditional Maximum Power Point Tracking (MPPT) algorithms. Traditional algorithm can be easily implemented using analog or digital devices. As traditional algorithms suffer from low efficiency, oscillations in steady state power and poor dynamic performance, a novel MPPT scheme using Linear Tangents based Perturb & Observe (LTP&O) is proposed in this paper. In order to validate their performance, proposed scheme and other traditional algorithms are simulated using Matlab/Simulink. Simulated results provide evidence that the proposed method has better accuracy, increased efficiency, low oscillation, improved steady state and dynamic performance compared to traditional methods. [ABSTRACT FROM AUTHOR]

In this paper, five most emerging renewable energy sources are analyzed. These emerging renewables are either special or advanced forms of the mainstream energy sources (solar, wind, geothermal, biofuels, biomass, and hydro) or brand new technologies. The five emerging renewable technologies discussed in this paper include marine energy, concentrated solar photovoltaics (CSP), enhanced geothermal energy (EGE), cellulosic ethanol, and artificial photosynthesis. Marine energy is divided into wave energy, tidal energy, tidal/ocean currents, salinity gradient, and ocean thermal energy conversion. CSP technologies are divided into parabolic troughs, linear Fresnel reflectors, parabolic dishes, and solar towers. The process for developing EGE reservoirs is also explained in detail. Cellulosic ethanol energy extraction is explained for both cellulolysis and gasification. Artificial photosynthesis is explained by considering semiconductor particles, electrolyzers, artificial leaves, and dye-synthesized solar cells. Each emerging renewable source's explanation is followed by its market share, challenges, implications for increased adoption, future prospects, and drawbacks. [ABSTRACT FROM AUTHOR]

Today solar power is still dominantly presented to be expensive source of electricity. However, the profitability of solar and other electricity generation technologies is typically evaluated with the Levelized Cost of Electricity (LCOE) approach. This paper questions the traditional investment evaluation logics of power production (LCOE) in the interesting case of rooftop PVs and based on customer value generation logics presents a new approach for evaluating the profitability of rooftop PV investments. The approach recognizes the value that PVs produce to real estate owners and utilize basic real estate investment models to evaluate the profitability of PVs. The results imply that, if PVs are considered as a part of the underlying property, rooftop PV systems are already today profitable in many European cities and can provide substantial returns on investment for property owners. More interestingly, the results imply that rooftop PV investments are most profitable in the dense urban cores instead of more remote (industrial) locations, and thus the current trend of urbanization seems to further strengthen the profitability of rooftop solar power. This paper points out that spatial locations drive the economic analysis of real estate, and thus it is likely that it will drive the economic analysis of decentralized on-site energy investments as well. [ABSTRACT FROM AUTHOR]

Owing to the rapid developments in the semiconductor and power electronics techniques, Photovoltaic energy is one of the interest area of concern in electrical power applications. Similarly, photovoltaic energy is clean, easily accessible, pollution-free and inexhaustible. It is normally important to operate the photovoltaic energy conversion systems closer to the maximum power point, to perk-up the output efficiency of the photovoltaic arrays. This paper elaborates the illustration and operating principles of twenty-seven state-of-the-art Maximum Power Point Tracking techniques that are prevalent in the photovoltaic systems. The selection of the photovoltaic system is dependent on diverse factors like cost, efficiency, complexity, technology and array dependency. Therefore, to come out with the design of a resourceful system, various aspects of different Maximum Power Point Tracking techniques have to be considered. An expressive comparative chart has been entailed at the end of this paper, which in future , will serve as a valuable reference to the photovoltaic system engineers. [ABSTRACT FROM AUTHOR]

In Australia during the past decade there has been a significant transformation of the electricity demand and supply sector. In five years from 2008 to 2013 the number of Australians installing solar photovoltaic (PV) technology grew from 8000 to more than one million. Governments in Australia used a range of policy incentives such as feed-in tariffs (FiTs) to encourage the uptake of solar PV and this had a range of consequences. Solar PV technology has transformed the residential consumer electricity market providing some consumers with greater choice in demand and supply of their power. This study contributes to the growing understanding of the role that demographic factors play in household uptake of solar PV technology. Based on a review of relevant literature and a multi-phased statistical analysis of more than 2 million people in south-east Queensland over five years, the paper highlights the complex interplay between socio-economics and household uptake. The paper identifies key demographic variables and quantifies their relative influence, and provides new insights into the role of age in solar PV uptake. This more nuanced explanation of the socio-economic variables influencing solar PV uptake offers an opportunity to more effectively and efficiently shape future policies and incentives. [ABSTRACT FROM AUTHOR]

In recent years solar energy has received worldwide attention in the field of renewable energy systems. Among the various research thrusts in solar PV, the most proverbial area is extracting maximum power from solar PV system. Application dof Maximum Power Point Tracking (MPPT) for extracting maximum power is very much appreciated and holds the key in developing efficient solar PV system. In this paper, a state of the art review on various maximum power point techniques for solar PV systems covering timeworn conventional methods and latest soft computing algorithms is presented. To date critical analysis on each of the method in terms of (1) tracking speed, (2) algorithm complexity, (3) Dynamic tracking under partial shading and (4) hardware implementation is not been carried out. In this regard the authors have attempted to compile a comprehensive review on various solar PV MPPT techniques based on the above criteria. Further, it is envisaged that the information presented in this review paper will be a valuable gathering of information for practicing engineers as well as for new researchers. [ABSTRACT FROM AUTHOR]

Building-integrated photovoltaics (BIPV), which can be integrated into the surface of a building (roof or facade), replacing conventional building materials, offer significant contributions to the achievement of net-zero energy buildings. However, fire safety is of vital concern in using BIPV as a construction system in buildings, and it is essential that the application of BIPV as building facades and roofs does not adversely affect the safety of construction products, building occupants and firefighters. As multifunctional products, BIPV modules must satisfy the fire safety requirements of both electrical and building-related sectors. This paper provides a comparison of normative frameworks applicable to BIPV modules in different countries. The comparisons show that IEC 61215 and IEC 61730 are the PV standards used in almost all countries, while the USA and Canada comply with UL1703. Regarding building regulations, the fire safety requirements of BIPV must comply with national/local building regulations. In the countries investigated, each country has fire regulations to guide the fire performance of building elements to which BIPV modules could be applied, including external walls, roofs/skylights, windows and other openings, and ancillary elements/attachments. This report also points out future research directions which would help develop BIPV fire prevention strategies globally. The review of regulations and standards in this paper makes a contribution to the clarification of the performance requirements of fire safety for BIPVs in the investigated countries for BIPVs, which remain barrier to the development of BIPV around the world. Furthermore, the future research directions suggested in this paper will inspire further research in this field. [Display omitted] • BIPV fire hazards include ignition, fire propagation, and hazards to building occupants and rescue operations. • The electrical fire safety requirements of PV modules are based on the same international standards. •The studied countries have different fire safety requirements for building elements. [ABSTRACT FROM AUTHOR]

Renewable Energy Sources (RESs) particularly photovoltaic (PV) and wind are becoming important sources for power generation. Frequently varying output of PV and wind caused by clouds movement, weather condition and wind speed make them an intermittent and unreliable sources when connected to grid. Connecting intermittent sources to grid introduces challenges in various technical aspects such as power quality, protection, generation dispatch control and reliability. In this context , leveling intermittent source׳s output is necessary inorder to maintain grid׳s stability. This paper is aimed at bringing out the latest comprehensive literature review on problems associated when the intermittent PV is connected to grid and the methods of smoothing the output power fluctuation from PV. This paper also briefly discusses control strategy built for battery energy storage pertaining to this issue. [ABSTRACT FROM AUTHOR]

China wishes to put more efforts in achieving its energy saving and emission reduction targets, for which photovoltaic (PV) power generation has showed great potential in many economic entities around the world. China also shows a strong sign of renewable energy booming: wind power and photovoltaic installed capacity soared in recent years. Actually, many countries around the world especially European countries have a longer history than China in PV application. But China has a unique energy industry development route, which may lead to a different PV prospective. To determine the uniqueness of China׳s PV development, data from China and 26 Organization for Economic Cooperation and Development (OECD) countries are collected. The Characteristics of China׳s PV industry is quantified and extracted in this paper. Indicators are selected from aspects of energy source, energy generation and energy consumption. Indicator distribution analysis, correlation analysis, and country cluster analysis methods are applied. 3 major characteristics of China׳s PV industry are extracted. Based on the key findings of this paper, it can be concluded that some inertial elements in the energy industry may be the biggest obstacles for China׳s PV development, and off-grid and distributed PV solutions are suggested to be better ways than concentrated PV power generation. [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]

Photovoltaics (PV) and air source heat pump (ASHP) are very important techniques for energy conservation and carbon reduction. It is essential to master the completed design idea and thermodynamic analysis method for the integration of PV and ASHP. Then, a design idea depending on the biggest power load of building appliances for the PV system was proposed in this paper. The thermodynamic analysis method for the PV integrated ASHP system considering the building process of PV modules was also provided here. To show the idea and method, the feasibility and exergy performance of an integrated PV-ASHP system (ASHP system driven by AC power inverted from PV) for domestic residential applications in Central-south China was investigated. Exergy efficiency and exergy consumption cost of the household PV-ASHP system were modelled based on the max PV conversion efficiency. The analyses show adequate efficacy of the PV-ASHP system with good thermodynamic and economic performance for their application in Central-south China. The PV-ASHP integrated system would have the best performance if the installed capacity of the individual PV system was decided by the required rating power of the ASHP system for HVAC (Heating, Ventilation and Air Conditioning). It could also be supported by the thermodynamic analysis results. The design idea and analysis method in this paper not only illustrate the potential and the validity of the integrated system in Central-south China but also would enable sustainable development and applying of solar energy and other renewable energy. [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]

Currently, energy development and utilisation are facing two problems in China: the energy crisis and the effects of global warming. An important means to solve the above problems effectively is to increase the intensity of the development and utilisation of photovoltaic system, which directly transforms the inexhaustible solar energy into the powerful green electrical energy. However, some problems plague the development of the photovoltaic industry. Due to these problems, the photovoltaic industry is seriously hindered in its efforts to develop sustainable. Therefore, accurately understanding the developing situation of the photovoltaic industry and analysing and solving the problems that occur during the development process of the photovoltaic industry in China are important topics of current research. This paper presents research results regarding these topics. First, this paper considers the present situation of the photovoltaic industry in China from three aspects: the power market, power generation industry policy and power generation technology level. Second, a discussion of the existing problems of the above three aspects is presented; in addition, based on the developing trends of renewable energy in China, development orientation of the photovoltaic industry are identified for years to come. Finally, strategies are proposed to promote the rapid development of the distributed photovoltaic industry in China. [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]

In order to promote the growth of renewable energy sector in Malaysia, feed-in tariff (FiT) mechanism has been introduced by Malaysian government in 2011, in accordance with Renewable Energy Act 2011 and Sustainable Energy Development Authority Act 2011. The tariff was enacted to overcome the shortcomings identified in the small renewable energy power (SREP) Program from 2001 to 2010. This paper highlighted some measures adopted to rectify the shortcomings identified during SREP, and the role of Sustainable Energy Development Authority (SEDA) in achieving the above mentioned task. The paper also includes the latest progress on renewable energy projects, especially those related to solar photovoltaic system. It is predicted that solar energy will become the main source of renewable energy in Malaysia by the year 2050. [ABSTRACT FROM AUTHOR]

Influenced by the international environment, price of photovoltaic (PV) products has continued to drop in recent years. The production enthusiasm of manufacturers was affected, and the market was in depression at once. To realize the expansion of domestic market, China has implemented many incentives since early 2009. This paper reviews the present status and development trend of the Chinese PV industry. It focuses on the turning point problem and draws the conclusions: First, there are still some obstacles to overcome, the key ones are the too low PV product price, industry overcapacity, unbalanced industrial demand and supply, cutbacks in foreign PV market and uncompetitive technologies. Second, the turning point of PV industry in China will come in the future if the problems in PV industry can be solved and the large-scale of the industry can be achieved. Third, the Chinese government is gradually clearing up the obstacles of the development of PV industry, and the turning point is on the way, maybe not later than 2020. At the end of the paper, suggestions are offered as references for the government. [ABSTRACT FROM AUTHOR]

This paper provides a review of methodologies for measuring the degradation rate, R D , of photovoltaic (PV) technologies, as reported in the literature. As presented in this paper, each method yields different results with varying uncertainty depending on the measuring equipment, the data qualification and filtering criteria, the performance metric and the statistical method of estimation of the trend. This imposes the risk of overestimating or underestimating the true degradation rate and, subsequently, the effective lifetime of a PV module/array/system and proves the need for defining a standardized methodology. Through a literature search, four major statistical analysis methods were recognized for calculating degradation rates: (1) Linear Regression (LR), (2) Classical Seasonal Decomposition (CSD), (3) AutoRegressive Integrated Moving Average (ARIMA) and, (4) LOcally wEighted Scatterplot Smoothing (LOESS), with LR being the most common. These analyses were applied on the following performance metrics: (1) electrical parameters from IV curves recorded under outdoor or simulated indoor conditions and corrected to STC, (2) regression models such as the Photovoltaics for Utility Scale Applications (PVUSA) and Sandia models, (3) normalized ratings such as Performance Ratio, R P , and P MPP / G I and, (4) scaled ratings such as P MPP / P max , P AC / P max and kWh/kW p . The degradation rate results have shown that the IV method produced the lowest R D and LR produced results with large variation and the largest uncertainty. The ARIMA and LOESS methods, albeit less popular, produced results with low variation and uncertainty and with good agreement between them. Most importantly, this review showed that the R D is not only technology and site dependent, but also methodology dependent. [ABSTRACT FROM AUTHOR]

Curtailment of distributed photovoltaic (PV) and battery energy storage systems will have significant implications for power system transition around the world. Australia offers a unique case study as it has highest installation rate of distributed-PV and growing fleet of battery energy storage systems. Distributed-PV and battery inverters in Australia are required to exhibit voltage-responsive power-quality response modes to prevent excessive voltage rise caused by increasing day-time energy exports, but these modes can curtail power output and limit the value that can be gained from the renewable energy assets. For the first time in Australia, this paper studies all three inverter power-quality response modes and develops novel algorithms to assess curtailment. The algorithms are applied to a real-world dataset of 1-sec distributed-PV and battery power measurements from 1300 residential households; therefore, data resolution is higher and sample size is larger than previous related studies. Using these datasets, the study compares the experienced curtailment between distributed-PV only sites and distributed-PV coupled with battery sites for the first time. The study investigates and quantifies the energy loss due to curtailment within the South Australia region with over 40% distributed-PV penetration which has the highest uptake in the world. The results show that average curtailment loss was 1.5% for distributed-PV only sites and 0.2% for distributed-PV coupled with battery sites, however, some sites were heavily impacted losing up to 25% of generation. The reasons for the larger curtailment loss were identified as wiring and network connection faults and high voltage set-points at households' respective local substations. Other potential reason for the heavily impacted sites is being located towards the end of the low voltage feeder, however this couldn't be verified due to lack of spatial data. The large variation in curtailed generation across sites raises concerns for system owners and suggests further inquiry into the power-quality response mode design and regulations. The study also examines inverter conformance using real-world operational data for all three power quality response modes for the first time, and the results showed a low rate of conformance according to the Australian Standards and there were various discrepancies in the execution of these modes which raises concerns considering the increasing importance of distributed-PV and battery inverter fleet in supporting network operations and security. The results therefore warrant further investigation into the reasons behind these discrepancies and devising appropriate mechanisms to tighten inverter conformance checks. • Energy curtailment is calculated for D-PV only and D-PV coupled with BESS sites • Average loss due to curtailment is less than 2% of total D-PV generation • Curtailment is greater for D-PV only sites than D-PV coupled with BESS sites • Some sites lose up to 25% of generation due to curtailment • The large variation of curtailment losses across sites raises concerns • Inverters showed low conformance in power quality response mode standards [ABSTRACT FROM AUTHOR]

In recent decades, Photovoltaic (PV) energy has made significant progress towards meeting the continuously increasing world energy demand. Besides that, the issue of conventional fossil fuels depletion as well as environmental pollution both contribute to the growth of PV technology. However, the deployment and implementation of photovoltaic systems remain as a great challenge, since the PV material cost is still very high. The low PV module conversion efficiency is another factor that restricts the wide usage of PV systems, therefore a power converter embedded with the capability of maximum power point tracking (MPPT) integrated with PV systems is essential to further the technology. This paper provides a comprehensive review of the available MPPT techniques, both the uniform insolation and partial shaded conditions. In order to appreciate the knowledge of MPPT concepts, several types of PV cell equivalent models are explained too. Conventional MPPT techniques have proven the ability to track the maximum power point (MPP) under uniform solar irradiance. However, under rapidly changing environments and partially shaded conditions, conventional techniques have failed to track the true MPP. For this reason, stochastic based methods and artificial intelligence have been developed with the ability to seek the true MPP under multiple peaks with good convergence speed. This paper analyses and compares both conventional and stochastic MPPT techniques based on the true MPP tracking capability, design complexity, cost consideration, sensitivity to environmental change and convergence speed. Comparatively, the stochastic algorithms and artificial intelligence show excellent tracking performance. The research on MPPT techniques is ongoing towards achieving a better performance in terms of the ease of implementation, low system cost and better tracking efficiency. [ABSTRACT FROM AUTHOR]

This paper compares and benchmarks different methods to calculate the hosting capacity of low voltage distribution systems for residential photovoltaic generation. The low voltage distribution system hosting capacity provides insight to the network planner and operator regarding the capability of the distribution system to accommodate new photovoltaic installations. In the literature, many different methods to calculate the hosting capacity of the distribution network exist, but they are demonstrated using different feeders and with different assumptions, making it difficult to compare different approaches. In this paper, a consistent benchmark of existing hosting capacity methods is performed. A publicly available real network of a semi-urban area is used to compare the different approaches in a consistent manner. A reference stochastic hosting capacity method is proposed, which considers all sources of uncertainty as well as operational and probabilistic limits. Hosting capacity definitions, based on both deterministic and stochastic methods, are evaluated based on their performance parameters and benchmarked. The performed analysis allows selecting the most appropriate hosting capacity definition and comparing results amongst systems. • Hosting capacity of low voltage distribution system is benchmarked. • Proposed reference stochastic hosting capacity method for solar photovoltaics. • Evaluated the influence of uncertainty sources, operational and probabilistic limits. • Real distribution system with actual load information was used. • Analysis helps to select the most appropriate hosting capacity definition. [ABSTRACT FROM AUTHOR]

Residential consumers in the U.S. have demonstrated a growing interest in rooftop photovoltaic (PV) systems, resulting in increased adoption over the last decade. However, this has diminished utility revenues, and policymakers have expressed concerns about inequitable consumer access to publicly-funded rooftop PV adoption incentives. In response to these concerns, policymakers and utility companies are changing their policies to discourage rooftop PV adoption. Alternative renewable energy models, such as utility-provided community solar programs, offer a potential solution. However, when designing such programs, it is important to consider the potential impacts on different system stakeholders, including utilities, policymakers, and solar installers. This paper describes an agent-based model that predicts the performance of different residential distributed solar models with respect to these stakeholders' objectives. In this model, consumer agents residing in an urban utility territory decide in each time-step whether they will adopt a particular renewable energy model, and the impacts of their adoption decisions on stakeholder performance metrics are captured over time. Simulation results suggest that if community solar program premium prices are set appropriately, all stakeholders can benefit: the utility can recover part of its revenue losses even as rooftop PV adoption increases, solar installers' businesses can thrive, and increased renewable energy adoption can be achieved equitably. The proposed modeling methodology can help to inform design decisions of distributed solar energy models that avoid benefiting some stakeholders at the unnecessary expense of others. • An agent-based model is developed to study solar adoption in the residential sector. • Consumer adoption behavior is studied for multiple solar-based energy models. • System-level approach with key energy stakeholders' objectives is considered. • Results show all stakeholders can benefit within a mutually beneficial arrangement. • Empirical examples are provided in support of the simulation results. [ABSTRACT FROM AUTHOR]

In this paper, some aspects of the performance of photovoltaic systems and wind generators are discussed. The performance of technologies for different types of wind generators is briefly explained, including the advantages and disadvantages of each type, and for different wind speeds. Technologies and techniques that improve the performance of different photovoltaic systems are also presented in a general way. In addition, a case study is presented to evaluate the use of wind generators and photovoltaic systems for small-scale industrial applications in the Tomar region (Portugal). The approach presented puts the focus on the small-scale applications for small/medium scale industries. These industries have a small/medium power consumption and most of them occupy limited spaces and the environmental conditions are those which exist in the place. The simulations show that there is a significant financial risk associated with the small-scale wind and photovoltaic systems. The purpose of this comparison is to ensure their technical and economic evaluation, leading to a better choice towards achieving zero net energy in buildings. The results obtained for the two technologies allow some important conclusions regarding their applications: photovoltaic systems have better performance than wind generators, photovoltaic systems have high-energy density, which leads to less need for space. • Performance analysis of small size wind generators and PV systems. • Brief review of performance enhancement techniques for PV and WT systems. • Evaluation of the WT and PV systems for small-scale industrial applications. • Technical and economic comparison of WT and PV small sizes. [ABSTRACT FROM AUTHOR]

Reference rules-of-thumb advise equator-facing orientations and slopes near the site's latitude as the optimal conditions for photovoltaic (PV) systems to maximize annual solar electricity production. However, if the electricity consumption profile is considered, this layout will most likely increase net load variance on the electricity grid at sunrise and sunset, which ought to be avoided. Making use of a variety of orientations and inclinations can help to minimize this impact, especially in cities where plentiful area of diversely oriented façades and rooftops is particularly relevant for broadening the peak of PV production throughout the day. Providing electricity not only around solar noon but also in the morning and late afternoon, when demand from residential buildings increases, helps to maximize self-consumption/-sufficiency and reduces costs for end-users and utilities. Until recently, due to high installation costs, there was little interest in this non-optimal PV systems configurations. In the last five years, however, the paradigm started to shift, triggered by the growing interest from municipalities that seek energy transition through currently more affordable PV systems and, on the other hand, by the duck-curve phenomena reported in pioneering "solar cities". This paper reviews studies that address the use of non-optimal azimuths and tilts to better match utility- and distributed-scale demand and supply. • Review of PV systems in non-optimal conditions and their value to the prosumers and the electricity system. • Reference rule of "south-/northwards, latitude ±10°" rarely applies. • Load-matching should be the main driver for PV systems sizing. • Urban environment has potential to load-match with PV at utility-scale. [ABSTRACT FROM AUTHOR]

Abstract Pumping of water requires excessive energy for its operation by consuming a massive amount of diesel, gasoline, electric power etc. The more promising alternative energies to perform the same operation without any energy cost are solar photovoltaic (PV) and wind. These fastest growing renewable energies are more reliable and well suitable for remote villages where there is no possibility of extending transmission lines. Furthermore, these systems are optimal for conditions like only small amount of water needed to be pumped for a particular time. Unlike conventional energy sources of electric power, the renewable energy sources are not dispatchable its power output cannot be controlled. In that case, it involves power conversion stages so that it would necessitate to design an advanced control strategy technique. Those control strategies greatly avoid and protects the system from detrimental operating conditions by monitoring input voltage, water flow, torque, power, pressure, speed and motor vibration etc. Henceforth the use of efficient control strategy not only increase the performance of system it also helps to increase the number of operational hours of solar PV and wind energy systems. In this manuscript, the research work of various control strategies carried out in solar PV and wind energy-based water pumping systems are presented. Additionally, this paper intends to discuss the energy management strategies applied for renewable energy fed water pumping system when the system assisted with third energy system (battery bank, fuel cell, etc). These benefited systems ensure good design, guarantees the control speed required for the motor, regulates the flow of water, assuring accurate operation for all conversion and finally, it maintains precise balance in between the renewable energy generated and power required by the load (pump). Highlights • The cost of water pumped by solar PV or wind is lower than the diesel systems along with the avoidance of CO 2 emissions. • In solar PV fed water pumping system the selection of suitable PV material with new technology will have great impacts on the reliability and performance of systems. This may also reduce the utilization of number of PV modules. • When looking for a simple solar PV fed water pumping system without any control unit complexity DC motors are much preferable. However, for submersible applications the regular maintenance of replacing brushes makes it to be unfit for it. • The finest power matching between the wind turbine and water pump must be ensured with generator and motor specification because the mismatch may lead to give poor overall efficiency along with degradation in rotor speed range. • The development on single stage power conversion stage for hybrid systems are needed to reduce complexity and to increase the efficiency of system. [ABSTRACT FROM AUTHOR]

Abstract This paper provides a critical literature review of the impact of snow accumulations on photovoltaic (PV) system electricity generation. The review quantifies the impact of snow, identifies factors that influence the generation loss, examines existing snow impact estimation techniques, and identifies mitigation strategies to reduce the impact of snow accumulations. Reported annual and monthly electricity generation losses resulting from snow accumulations on photovoltaic systems show that annual electricity generation losses were less than 10% in most climates; however, monthly generation losses throughout the winter were generally higher than 25%. The influences of climatic characteristics and system characteristics on the impact of snow were examined individually, and the codependence between influence factors was also discussed where relevant. Estimation techniques for electricity generation loss due to snow cover were summarized. Relatively accurate estimates are achievable by several models when considering ambient temperature, solar irradiance, and snow depth. Ten mitigation methods were identified as having the potential to reduce the impact of snow on PV system electricity generation and were discussed qualitatively. This review provides system designers and operators with the information required to identify how to manage the effect of snow on PV systems and highlights the need for researchers to develop ways to reduce and predict the impact. Highlights • Electricity generation loss due to snow on PV systems is generally less than 10%. • Winter month generation loss due to snow is generally higher than 25%. • Climate and system characteristics have a significant impact on loss. • Threshold type snow coverage prediction models are most effective. • No method currently exists to mitigate the impact of snow on PV panels. [ABSTRACT FROM AUTHOR]

Abstract Owing to the wind and photovoltaic (PV) potential in Brazil, the country has recently seen increased exploration into the construction of wind-PV hybrid plants. However, as specific criteria for contracting this type of project have not yet been developed, this paper presents a model to assist the government in contracting projects that maximize the socioeconomic well-being of the Brazilian electricity sector. For this, multiobjective programming is used to simultaneously handle two objective functions—maximally reducing emission density and minimizing the levelized cost of electricity (LCOE)—with the aid of the mixture arrangement technique. In this respect, the optimization method called normal boundary intersection (NBI) is applied to solve the multiobjective problem and construct the Pareto frontier. Additionally, a metric based on the ratio between entropy and the global percentage error (GPE) is used to identify the optimal Pareto solution. The model was applied to determine optimal configurations for wind-PV powerplants in twelve Brazilian cities, and the results obtained reveal the capacity of the model to indicate the optimum configuration according to the wind and PV potential of each city. Highlights • The use of renewable energy sources has been encouraged in Brazil. • The construction of PV-wind hybrid plants has been recently explored. • Normal Boundary Intersection is used to simultaneously handle two objective functions. • Reduced emission density and LCOE were optimized in twelve Brazilian cities. • Results reveal the capacity of the model to indicate the plants optimum configuration. [ABSTRACT FROM AUTHOR]

The Sun is the primary energy source for all life on Earth. Solar energy is clean and is available all over the world. The total energy produced, in 2016, was 7236 MWh, while the total consumed was 6660 MWh. The average photovoltaic energy generated was 255 MWh, which accounts for 3.5% of the total production and 8.2% of the RES (3096 MWh). Investments in renewable energy in Romania began in late 2008, when Green Certificates were granted by Law no. 220. In this paper, we review the photovoltaic system development in Romania, from 2011, when the market began to develop, to the present day. The climate change and air pollution have to be slowed down and reduced by implementing renewable and sustainable solutions in order to generate electricity. The photovoltaic industry has an important role in Romania's development, both economically and environmentally and by having the “unlimited resource” advantage, it is a good alternative to fossil fuels. Now, the largest solar park in Romania, with 332,000 operational PV units, located in Ucea de Sus, Brasov County and commissioned in 2013, has an installed capacity of 82 MW, and covers a land surface of 200 ha. 178 years ago, French physicist Edmond Becquerel discovered the photoelectric effect, in 1839. At the moment, the typical power of solar PV modules is less than 500 W, depending on efficiency and temperature sensitivity. Currently, long-term research on photovoltaic cells focus on increasing the power output, increasing the efficiency and reducing the temperature sensitivity. [ABSTRACT FROM AUTHOR]

Energy is essential for economic development and growth. With the rapid growth of development and the drive to expand the economy, society demands more electricity. Coupled with the realisation that unsustainable energy production can have a detrimental effect on our environment. Solar energy is the most prolific method of energy capture in nature. The economic drive to make solar cells more cost effective and efficient has driven developments in many different deposition technologies, including dipping, plating, thick film deposition and thin film deposition. Typically, in order for solar energy to work efficiently and supply energy to a building, a very large amount of space is required, in the form of rooftops or land, in order to install solar panels; these solar panel space requirements are a large impediment to practical usage. This drawback drove researchers to come up with transparent solar cells (TSCs), which solves the problem by turning any sheet of glass into a photovoltaic solar cell. These cells provide power by absorbing and utilising unwanted light energy through windows in buildings and automobiles, which leads to an efficient use of architectural space. There are approximately nine transparent photovoltaic (TPV) technologies under development, and studies regarding these technologies aim to achieve high transparency along with electrical performance that is compatible with solar panels that are sold in the market. The main objective of this review paper is to state all the latest reported technologies from the year 2007 onwards on transparent photovoltaic technologies with at least 20% average transmission. This includes demonstrating the process used in each technology (including the materials and the methods) and explaining its advantages and disadvantages from a performance, aesthetic and financial perspective. Therefore, this study provides a crucial review on the latest developments in the field of TSCs. [ABSTRACT FROM AUTHOR]

Renewable energy generation has experienced rapid growth in the last few years, with close to $ 330 billion investment in 2017. To promote renewable energy generation, the European Union established an objective of achieving 20% renewables in the consumption by 2020. Compared to other renewabl e sources, solar power has reduced environmental impact. An MPPT (maximum power point tracking) controller is used to increase the energy gathered from a solar panel. Selection of appropriate converter is one of the challenge since that has an impact on behaviour of the PV (photovoltaic) system. In recent years, many converters have been reported in the literature. This paper presents a detailed review of various converter topologies such as SEPIC (single-ended primary-inductance converter), boost, buck-boost and flyback which are used to achieve the desired voltage level on grid output. The pros and cons of these converters are discussed. Review shows that interleaving and coupled inductor based topologies can offer advantages such as high efficiency and reduced switching loss. This study is not limited to reviewing topologies, rather discusses PV array configurations, advanced MPPT methods, advanced converters and comparisons in terms of hardware complexity, cost and efficiency. Finally, a summative analysis of topologies suitable for PV applications along with MPPT techniques are listed. This review can be employed for evaluating appropriate topology of converter in PV applications. [ABSTRACT FROM AUTHOR]

From the last few decades, due to the escalating requirement of heat and electricity, the relative utilization of Photovoltaic/thermal (PV/T) system has enlarged as compared to the photovoltaic or solar thermal system alone due to better performance of combined PV/T systems when compared to the conventional ones. PV/T hybrid systems generate both electrical and thermal energy concurrently, giving it a broad variety of applications. Recently, different nanoparticles mixed with base fluid (Nanofluid) have been used in these hybrid systems resulting in attracting the attention of numerous researchers. Due to its improved thermal conductivity nanofluid can be used as an optical filter and proficient coolant in PV/T systems. In the last years, much research has been focused on this domain because it is crucial for the design of sustainable and environmentally friendly energy systems. The primary focus of this review is to accomplish the briefing of diverse PV/T technologies at the outset together with aspects of their efficiencies, structure, thermal governing expressions and their applications as well as the latest technologies and parameters which profoundly affect the PV/T collector performance. We have also reviewed the various positive and adverse effects on the environment safety level by applying these solar techniques for the energy production as compared to the conventional energy sources techniques. As the solar techniques are tremendously helpful for the environment in several ways but at the same deployment of these resources on the wide-scale may lead to adverse implications for the environment. Moreover, the variations in the performance efficiency of the PV/T system using nanofluids, and finally, the suggestions for future research directions are presented. The outcome of this review paper would give an overview of further enhancements in solar PV/T systems with high practicability for extensive relevance in energy supply at all levels in the vicinity of future. [ABSTRACT FROM AUTHOR]