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In the context of energy conversion from renewable sources to distribution grids (insulated or not), a converter is often required to transfer energy from a low voltage source towards three-phase grids. This paper presents the HW design, the simulation results, and the conversion performance of a CSI converter intended to interface low-voltage renewable sources to three-phase grids. The main focus of this paper is to obtain the best performance in terms of voltage increase towards the output stage while maximizing the conversion efficiency. In comparison with the currently used energy conversion systems for small photovoltaic systems, hereafter some solutions were adopted to level and maximize the energy flow from the source to the DC-link and improve the quality of current supplied in terms of harmonic distortion. The proposed system is composed of two conversion stages: the first, voltage-to-current, the second current-to-current via a three-phase CSI bridge modulated with the SVM technique. The stages are not completely decoupled from an electrical point of view; therefore, in order to mitigate the effects of these interactions, synchronization strategies have been adopted. [ABSTRACT FROM AUTHOR]

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

Fossil fuels, the predominant energy source in the United States, have been identified as major contributors to environmental pollution through the release of harmful emissions. As a countermeasure, there has been an increasing focus on the exploration and development of cleaner energy alternatives to alleviate the environmental degradation caused by fossil fuels and to satisfy the growing energy needs. This study conducted scenario analyses to evaluate the impact of integrating solar energy into specific US power grids on reducing carbon emissions. The analysis encompassed electrical systems within California, New England, New York, and the Southwest, utilizing datasets from the Energy Information Administration and National Renewable Energy Laboratory. The Energy Information Administration dataset includes information on net generation according to each source and carbon emissions according to fuel type, whereas the National Renewable Energy Laboratory dataset provides hourly projections for 6000 theoretical photovoltaic installations and detailed solar energy output data every five minutes over a year. Our findings indicated a notable decrease in carbon dioxide emissions following the introduction of solar power facilities. The most significant reductions were observed in the Southwest and California, attributed to solar plant integration. Conversely, New York and New England were identified as regions requiring additional policy measures and incentives to meet the emission reduction goals. [ABSTRACT FROM AUTHOR]

The constant increase in energy demand and the need to reduce the carbon footprint on the environment has put countries in a race against time, looking for alternative resources or ways to supply this need. One of the main resources is solar radiation, which can be used to generate energy, initially on a small scale, but in recent years has been directed towards supplying large cities. The economic, political, and social investment must respond to planning and expansion criteria in order to generate feasible proposals. Through simulation of a real electrical system, the voltage instability was determined, which was corrected at software level by entering a photovoltaic solar plant, being this dimensioned from the PV curve obtained. Finally, the optimal location for the development of a solar photovoltaic plant among four possible scenarios was obtained through the application of an optimization algorithm. This approach was converted into an alternative applicable to different geographical locations. [ABSTRACT FROM AUTHOR]

In the context of energy conversion from renewable sources to distribution grids (insulated or not), a converter is often required to transfer energy from a low voltage source towards three-phase grids. This paper presents the HW design, the simulation results, and the conversion performance of a CSI converter intended to interface low-voltage renewable sources to three-phase grids. The main focus of this paper is to obtain the best performance in terms of voltage increase towards the output stage while maximizing the conversion efficiency. In comparison with the currently used energy conversion systems for small photovoltaic systems, hereafter some solutions were adopted to level and maximize the energy flow from the source to the DC-link and improve the quality of current supplied in terms of harmonic distortion. The proposed system is composed of two conversion stages: the first, voltage-to-current, the second current-to-current via a three-phase CSI bridge modulated with the SVM technique. The stages are not completely decoupled from an electrical point of view; therefore, in order to mitigate the effects of these interactions, synchronization strategies have been adopted.

The exponential growth of population and industries has brought about an increase in energy consumption, causing severe climatic and environmental problems. Therefore, the move towards green renewable energy is being ever more intensified. This study aims at estimating the rooftop solar power production for Tehran, the capital city of Iran, using a Geospatial Information System (GIS) to assess the big data of city building parcels. Tehran is faced with severe air pollution due to its excessive fossil fuel usage, and its electricity demand is increasing. As a result, this paper attempts to provide the quantified solar power potential of city roof tops for policymakers and authorities in order to facilitate decision-making in relation to integrating renewable energies into the power production infrastructure. The results shows that approximately 3000 GWh (more than 14% of the total electric energy consumption) of solar power can be produced by the rooftop PV installations in Tehran. The potential nominal power of rooftop PV installations is estimated to be more than 2000 MW, which is four times the current installed PV capacity of the whole country. The findings of the study suggest that there is great potential hidden on the rooftops of the city, which can be utilized to assist the power systems of the city in the longer run for a more sustainable future. [ABSTRACT FROM AUTHOR]

Copyright of Energy Policy Journal / Polityka Energetyczna is the property of Mineral & Energy Economy Research Institute of the Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two types of Cu(In,Ga)Se2 (CIGS) thin-film solar modules, differing only in the patterning procedures, were exposed to a high voltage (1 kV) across the thickness of the soda-lime glass substrate. Both module types utilized a cell stack, and in particular, a molybdenum back contact, which was optimized for CIGS solar cells with enhanced stability against potential-induced degradation (PID). A standard module with regular patterning lines for monolithic interconnection consists of P1, P2, and P3 lines, with P1 separating the back contact, P2 establishing the contact between the front contact TCO of one cell to the Mo back contact of the next cell, and P3 isolating the front contact from one cell to the next cell. However, modules employing this cell stack with regular patterning lines P1, P2, and P3 suffered considerably from PID while modules with a P1 groove filled with an insulator showed greatly enhanced stability similar to the pure single cell without P1 patterning. PID manifests once a specific quantity of charge has been transmitted through the soda-lime glass substrate, while the molybdenum back contact of the cell functions as the cathode, maintaining a negative bias relative to the substrate's backside. As a consequence of PID, sodium is increased in the adsorber for susceptible cells. Therefore, inhibiting sodium transport through the P1 groove by filling it with an insulating material enhances the PID stability of the modules considerably. As a result, the modules with a filled P1 groove showed similar stability to the single solar cells with an improved PID stable cell stack, while modules without a filled P1 patterning were much more susceptible to PID, although a cell stack with greatly enhanced PID stability was used. In summary, the presented strategy to fill the P1 groove offers a viable and novel path to improved PID stability of CIGS modules. [ABSTRACT FROM AUTHOR]

Fossil fuels, the predominant energy source in the United States, have been identified as major contributors to environmental pollution through the release of harmful emissions. As a countermeasure, there has been an increasing focus on the exploration and development of cleaner energy alternatives to alleviate the environmental degradation caused by fossil fuels and to satisfy the growing energy needs. This study conducted scenario analyses to evaluate the impact of integrating solar energy into specific US power grids on reducing carbon emissions. The analysis encompassed electrical systems within California, New England, New York, and the Southwest, utilizing datasets from the Energy Information Administration and National Renewable Energy Laboratory. The Energy Information Administration dataset includes information on net generation according to each source and carbon emissions according to fuel type, whereas the National Renewable Energy Laboratory dataset provides hourly projections for 6000 theoretical photovoltaic installations and detailed solar energy output data every five minutes over a year. Our findings indicated a notable decrease in carbon dioxide emissions following the introduction of solar power facilities. The most significant reductions were observed in the Southwest and California, attributed to solar plant integration. Conversely, New York and New England were identified as regions requiring additional policy measures and incentives to meet the emission reduction goals.

This report describes the design development process and recommendations of a Community-Scale Zero Net Energy Master Plan for a residential block in Oakland, the Oakland EcoBlock. The recommended master plan includes an integrated system of energy efficiency retrofits, a direct current solar/storage/electric vehicle microgrid, alternating/direct current houses, and water efficiency retrofits with rainwater capture. The recommended master plan is projected to be close to zero-net energy (95 percent) for homes, reduce carbon emissions by 65 percent at the block scale (including transportation), and reduce water use 60–70 percent. The integrated system of energy efficiency and a direct current solar/storage/electric vehicle (EV) charging microgrid is the first of its kind at the residential block scale. This breakthrough because the deep energy efficiency retrofit savings free up enough capacity in the solar supply and storage to enable residents to switch from natural gas to electricity for heating and domestic hot water and to provide EV charging for 33 percent of vehicle miles traveled. The savings in household transportation costs are a game changer because when combined with savings in the electric and water utility bills, the total cash flow savings are projected to fund the capital improvements of the proposed systems. This project’s benefits include lower and more predictable utility bills; greater resiliency because the system can operate during outages, and vastly improved indoor air quality by reducing natural gas consumption. The local energy storage reduces peak demand for the utility. California benefits from a model that exceeds the targets for reductions in energy consumption and carbon emissions and the reductions in water use address California’s severe water challenges. The Oakland EcoBlock is a transformative model for accelerating the rapid deployment of advanced energy communities.

In non-uniform conditions, the power curve of a solar plant can vary significantly, which can affect the performance of the system. In such conditions, the configuration of the panels can help reduce the mismatch losses. Although dedicated electronics may be helpful in reducing a panel's mismatch, the panel configuration is a recent solution that can also reduce a panel's overall power consumption and mismatch losses. Hence in this paper Sider Web Tie (S-B-T) PV panel configuration is proposed. A test case of 5 X 5 200 W PV panel is considered. The proposed S-B-T PV configuration is implemented under real time PSC’s in comparison with Series-Parallel (S-P), Total Cross-Tied (T-C-T), Triple-Tied (T-T), Bridge-Link (B-L) configurations. The factors such as PV mismatch losses, Max. current and voltage, OC Voltage, SC Current that influence the performance of the system are investigated. In all the cases proposed Spider Web Tie (S-B-T) PV configuration exhibits the superior performance. [ABSTRACT FROM AUTHOR]

The exponential growth of population and industries has brought about an increase in energy consumption, causing severe climatic and environmental problems. Therefore, the move towards green renewable energy is being ever more intensified. This study aims at estimating the rooftop solar power production for Tehran, the capital city of Iran, using a Geospatial Information System (GIS) to assess the big data of city building parcels. Tehran is faced with severe air pollution due to its excessive fossil fuel usage, and its electricity demand is increasing. As a result, this paper attempts to provide the quantified solar power potential of city roof tops for policymakers and authorities in order to facilitate decision-making in relation to integrating renewable energies into the power production infrastructure. The results shows that approximately 3000 GWh (more than 14% of the total electric energy consumption) of solar power can be produced by the rooftop PV installations in Tehran. The potential nominal power of rooftop PV installations is estimated to be more than 2000 MW, which is four times the current installed PV capacity of the whole country. The findings of the study suggest that there is great potential hidden on the rooftops of the city, which can be utilized to assist the power systems of the city in the longer run for a more sustainable future.

Using the desktop tool (Energy3D) for modelling sustainable buildings and solar power generation, this work predicts the performance of a scalable photovoltaic (PV) power plant composed of south-facing parallel racks in Muscat (the capital of the Sultanate of Oman, latitude 23.6 degrees North). The pilot PV power plant has 3,535 PV panels of peak capacity 300 Wp, leading to a total theoretical peak capacity of 1,060.5 kWp. It covers a land area of 10,000 square meters (1 hectare). The work focuses on the sensitivity of the output electricity to the tilt of the PV panels. The analysis shows that a fixed year-round optimum tilt angle offers 6.6% less annual yield than the single-axis-horizontal tracking system (continuously varying tilt). Adopting a dual-tilt system (tilt of 8.6 degrees during April–September and 38.6 degrees during October–March) reduces this gap to 2.5%. The PV power plant can provide an annual yield of 1.794 GWh under a dual-tilt setting, and 1.92 GWh with single-axis-horizontal solar tracking. Some results are provided on a per-square-meter basis, for easy estimation of land needs. The accuracy of estimating electric annual yield was tested by benchmarking with the Global Solar Atlas (GSA) online tool by the World Bank, for the case of fixed optimum tilt.

According to the 7th goal of sustainable development concluded by the United Nations (UN), energy should become clean and accessible for every human being on the planet in the upcoming decades. Clean energy is often used as a synonym for renewable, sustainable or green energy, words which are associated with a concept of low-impact technologies. However, renewable energies (REs) also have a set of negative environmental impacts (EIs), which can be identified and assessed through an EI Assessment (EIA) and/or a Life Cycle Assessment (LCA). This article focuses on the revision of EIs documented in LCA studies for solar photovoltaic (PV) systems (SPVSs), the most common type of modern REs to satisfy energy demand globally. Although different LCA studies include various environmental assessment categories, five categories were selected for analysis, namely global warming potential (GWP), land use, biodiversity loss, human health (HH) and waste generation. The results show that documented EIs of SPVSs from LCAs depend not only on the technology, context and scale of the project, but also on the objective and scope of each study. Still, this article summarizes orientational values for the GWP, land use and fatal bird accidents related to SPVSs. Further, the research reveals the need for complementary approaches such as EIAs or toxicity studies for the assessment of biodiversity loss as well as the impacts on HH, and the lack of an existing waste management system for the million tons of waste soon to be disposed. [ABSTRACT FROM AUTHOR]

Using the desktop tool (Energy3D) for modelling sustainable buildings and solar power generation, this work predicts the performance of a scalable photovoltaic (PV) power plant composed of south-facing parallel racks in Muscat (the capital of the Sultanate of Oman, latitude 23.6 degrees North). The pilot PV power plant has 3,535 PV panels of peak capacity 300 Wp, leading to a total theoretical peak capacity of 1,060.5 kWp. It covers a land area of 10,000 square meters (1 hectare). The work focuses on the sensitivity of the output electricity to the tilt of the PV panels. The analysis shows that a fixed year-round optimum tilt angle offers 6.6% less annual yield than the single-axis-horizontal tracking system (continuously varying tilt). Adopting a dual-tilt system (tilt of 8.6 degrees during April–September and 38.6 degrees during October–March) reduces this gap to 2.5%. The PV power plant can provide an annual yield of 1.794 GWh under a dual-tilt setting, and 1.92 GWh with single-axis-horizontal solar tracking. Some results are provided on a persquare-meter basis, for easy estimation of land needs. The accuracy of estimating electric annual yield was tested by benchmarking with the Global Solar Atlas (GSA) online tool by the World Bank, for the case of fixed optimum tilt. [ABSTRACT FROM AUTHOR]

Abstract Background The 2018 European Renewables Directive sets a binding target of 32% of renewable energy generation by 2030. Free-field photovoltaic plants are characterised by significant land use and material flows. Although country-level data on installed power is available, information about the spatial distribution of PV plants is rare. When the first photovoltaic systems will reach their end-of-life on a large scale in 2035, economic, technological and ecological challenges will arise. Methods The study explores the market development of photovoltaic power in the EU countries from 2008 to 2017 by preparing statistical data and Google mapping of free-field PV plants. Different approaches to assessing the land use of free-field PV systems compared to other energy systems are investigated. A comprehensive literature review addresses key issues of PV module waste treatment, hazardous constituents and their leakage in case of module breakage as well as financial issues of decommissioning and recycling and re-use of used modules. Results Most of the European PV electrical energy is generated by approximately 17,000 widely distributed free-field plants predominantly installed in lowlands. A local in-depth study shows that roof-top plants contribute less than 5% to the total PV energy generation in an area without extensive expansion to industrial buildings. Small amounts of hazardous substances that are typically present in PV modules are unlikely to affect the environment during normal operation of the system, but the question of leakage from broken end-of-life modules is not sufficiently clarified. While in the EU, the recycling and disposal costs are covered by producer fees and expected raw material profits; the financing of the decommissioning of thousands of PV free-field plants is still an open issue. Conclusions The land use of free-field PV systems should be analysed in more detail. Concerning hazardous substances, there seems to be an emerging consensus in literature that the leaching behaviour of metals from broken PV module pieces is inadequately simulated by current waste characterisation protocols. It is recommended to pay greater attention to financing the decommissioning of free-field commercial and industrial scale PV systems.

Roof with metal sheets and PV‐systems – practical knowledge Recently it was legally stipulated in some German states that a solar power system has to be installed on new buildings. A legislative initiative on a federal level is also prepared. A solar power system (named PV‐system in the following) can consist of photovoltaic elements for producing electricity or solar elements for heating primarily water. Light weight metal sheets are often used for the roofing of industrial buildings, on which the PV‐system is installed. Prefabricated metal sheets consist of e. g. trapezoidal profiles, standing seam profiles and sandwich panels. Special fixing systems are used that fit for the individual type of metal sheet. The experience has shown that even though PV‐systems are put on metal sheets since many years, the special topics for the application are not known or not taken into account. The following article goes into detail to the before mentioned metal sheets regarding the formal basis, loadings, static design, occasional or repeated access of persons and requirements due to corrosion. [ABSTRACT FROM AUTHOR]