•PVT systems in Central Europe are an effective path towards zero carbon buildings.•They can contribute notably to enhancing sustainability and energy security.•Their profitability and success will ...depend on the right policies and regulations.•The consumer right to export energy to the network is vital for this success.
In central European countries, district heating is a common and standard way to cover the residential heat demand. While the consumers are connected to the heat network and electricity grid, they are being increasingly encouraged to become prosumers by having own distributed renewable energy generation. At the same time, the energy performance requirements for new and renovated buildings are setting progressively higher energy efficiency standards. This tendency is effectively reducing the carbon footprint of the residential sector in Central Europe and will eventually lead to low and zero carbon buildings becoming the standard. One of the emerging technologies within this approach are Photovoltaic thermal hybrid solar collectors, which combine heat and power generation and are easy to integrate in buildings. In this study, the possibility to use such a system, supported by a heat pump, in a Central European multi-family house is addressed. Three configurations are considered; the building, the hybrid and district heating configuration. In the building configuration the heat from the solar collectors is used directly for domestic hot water and space heating and no use is made of excess heat. In the hybrid configuration, the direct heat consumption in the building is prioritized, while excess heat is exported to the district heating network. Finally, in the district heating configuration, the solar system operates as a micro-plant that supplies all produced heat to the district heating network. The study shows that the use of Photovoltaic thermal hybrid solar collectors in combination with district heating provides important benefits in terms of sustainability, energy security, carbon abatement and costs. Thereby, configurations that can export heat to the network have better energy efficiency and result more profitable.
Solar energy is an important alternative energy source that leads to sustainable development of district heating (DH) systems. The aim of this paper is to analyze optimal integration of photovoltaic ...thermal hybrid (PVT) technology in DH systems by covering industrial power consumption and heat demand of buildings in the Northern European climate.
The article compares several different scenarios for the particular case study in order to find the optimal solar system design. The scenarios differ with the size of the installed PVT area as well as an excess power utilization setup. The hourly load and solar energy generation alignment analysis determines the total achievable solar fraction and other parameters for each scenario.
The results show that it is economically beneficial to convert excess power to heat when the market price of electricity is lower than the DH heat tariff. This is done with the restriction that the heat demand is higher than solar heat generated. The higher solar fraction is obtained in scenario of maximal PVT area (3000 m2) installation with a power accumulation added. Solar fraction reaches 38% of total heat and power consumption. However, this scenario also has the highest costs and incomes. The calculated value of levelized costs of energy (LCOE) for all scenarios is lower than used reference costs of energy.
The total avoided emissions are higher for the scenarios without power accumulation. The specific avoided CO2 emission costs show that the optimal scenario is with 2000 m2 PVT area installed.
•The solar power and heat generation were modeled on hourly bases.•The obtained results were aligned with the heat consumption.•Excess solar power is used in three different ways.•Most of income from installed PVT system comes from heat selling.•The calculated value of LCOE is lower than used reference costs of energy.
This paper addresses the requirements of electrical energy for an isolated island of Masirah in Oman. The paper studied the possibility of using sources of renewable energy in combination with ...current diesel power plant on the island to meet the electrical load demand. There are two renewable energy sources used in this study, solar and wind energy. This study aimed to design and evaluate hybrid solar/wind/diesel/battery system in terms of cost and pollution. By using HOMER software, many simulation analyses have been proposed to find and optimize different technologies that contain wind turbine, solar photovoltaic, and diesel in combination with storage batteries for electrical generation. Four different hybrid power systems were proposed, diesel generators only, wind/diesel/battery, PV/diesel/battery, and PV/wind/diesel/battery. The analysis of the results shows that around 75 % could reduce the cost of energy by using PV/wind/diesel hybrid power system. Also, the greenhouse emission could be reduced by around 25 % compared with these by using diesel generators system that currently utilize in the Masirah Island. The solar/wind/diesel hybrid system is techno-economically viable for Masirah Island.
In support of the clean energy transition, rooftop photovoltaics (RTPV) deployment has been globally advocated, enabling citizens as energy prosumers within their localised building environment. ...However, the effectiveness of RTPV implementation is influenced by diverse bioclimatic conditions. Here, we provide a critical climate-related RTPV characterisation across the globe, consisting of a comprehensive assessment of RTPV performance, taking into account global horizontal irradiation (GHI) and local environmental parameters, including space conditioning requirements in different climatic zones. Additionally, we examine the technological advancements aimed at improving efficiency in RTPV systems.
Within a meta-data analysis, we find that the RTPV systems offer various advantages in terms of building overall energy performance, particularly in moderate and warm climates. We observe that typical or increased insulation values can offset the RTPV effect in uninsulated roofs. This is essential in regions with cold climates and helps to mitigate increased heating requirements during winters or higher cooling demands during summer nights. A relationship between the ratio of building space coverage to PV surface and GHI is proposed for low-energy buildings to calculate the space requirements for achieving net zero buildings, globally. Moreover, in hot climates, cooling the RTPV surfaces can enhance efficiency by up to 20 % and increase power output by up to 15 %. By advancing RTPV efficiency to 30 % with emerging technologies, the decarbonisation of high-rise buildings can be facilitated, alongside energy efficiency and RTPV implementation measures. Striking a balance between thermal insulation needs, we conclude that RTPV offers wide benefits across different climatic conditions.
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•Rooftop PV deployment is crucial for decarbonisation and clean energy transition.•RTPV is energy-beneficial in moderate and warm climate conditions.•RTPV energy drawbacks in cold climate and hot climates can be mitigated.•PV efficiency of 30 % can accelerate the transition to NZEB in all climatic conditions.
The efficiency of metal halide perovskite solar cells (PSCs) has skyrocketed; however, defects created by aging precursor solutions and during crystallization pose a significant barrier to the ...reproducibility and efficiency of solar cells. In this work, fluoro‐N,N,N″,N″‐tetramethylformamidinium hexafluorophosphate (F‐(CH3)4CN2PF6, abbreviated as TFFH) is introduced to stabilize precursor solution and improve crystallization dynamics simultaneously for high‐performance formamidinium lead iodide (FAPbI3)‐based perovskite indoor photovoltaics. The TFFH stabilizes the precursor solution by inhibiting oxidation of I− and reducing newly generated I0 to I−, and passivates undercoordinated Pb2+ by interacting with the Pb─I framework. Time‐resolved optical diagnostics show prolonged perovskite crystallization dynamics and in situ defect passivation due to the presence of strong FA+···TFFH···Pb─I interaction. Simultaneous regulation of precursor solution and crystallization dynamics guarantee larger perovskite grain sizes, better crystal orientation, fewer defects and more efficient charge extraction in PSCs. The optimized PSCs achieve improved reproducibility and better stability and reach an efficiency of 42.43% at illumination of 1002 lux, which is the highest efficiency among all indoor photovoltaics. It is anticipated that the concurrent stabilization of solutions and regulation of crystallization dynamics will emerge as a prevalent approach for enhancing the reproducibility and efficiency of perovskite.
It is found that the TFFH additive can inhibit the oxidation of I−, eliminating I0, Pb0, and uncoordinated Pb2+ defects and control crystallization kinetics by the strong FA+···TFFH···Pb─I interaction. Simultaneous regulation of precursor solution and crystallization dynamics mean the optimized solar cells achieve improved reproducibility and stability, and reach an efficiency of 42.43% at illumination of 1002 lux.
Photovoltaic (PV) energy conversion of sunlight into electricity is now a well-established technology and a strong further expansion of PV will be seen in the future to answer the increasing demand ...for clean and renewable energy. Concentrator PV (CPV) employs optical elements to concentrate sunlight onto small solar cells, offering the possibility of replacing expensive solar cells with more economic optical elements, and higher device power conversion efficiencies. While CPV has mainly been explored for highly efficient single-crystalline and multi-junction solar cells, the combination of thin-film solar cells with the concentration approach opens up new horizons in CPV. Typical fabrication of thin-film solar cells can be modified for efficient, high-throughput and parallel production of organized arrays of micro solar cells. Their combination with microlens arrays promises to deliver micro-concentrator solar modules with a similar form factor to present day flat-panel PV. Such thin-film micro-concentrator PV modules would use significantly less semiconductor solar cell material (reducing the use of critical raw materials) and lead to a higher energy production (by means of concentrated sunlight), with the potential to lead to a lower levelized cost of electricity. This review article gives an overview of the present state-of-the-art in the fabrication of thin-film micro solar cells based on Cu(In,Ga)Se2 absorber materials and introduces optical concentration systems that can be combined to build the future thin-film micro-concentrator PV technology.
•Application of RCM, based on FMEA, to photovoltaic systems.•MBS and FMEA determine RPN.•New maintenance plan aimed to reduce fixed RPN of criticalities.•Lower values of RPN by FMEA and major ...reliability of system obtained.
There have been many scientific advances in the improvement of renewable energy systems. Recently, considerable interest has been given to their optimized management during their service life due to a large increase in the number of new renewable energy source power plants. High reliability levels are as important as high yields in order to maximize the useful green energy produced. Solar energy has been one of the most popular and exploited renewable sources in the market and therefore improvements in its efficiency and reliability have had a considerable impact. All energy systems require an increase in their conversion efficiency to reduce the consumption of primary energy. Moreover, the optimization of the performance of photovoltaic systems has increased their incidence as renewable sources in global power generation and has boosted their profitability. A failure of the components and sub-components of a working energy system cause two main issues; the first direct implication for the plant is the damage of the components and sub-components, and the second indirect implication is the consequent lack of energy production due to the plant being out of order. Furthermore, unforeseen failures of the components increase the uncontrollability of photovoltaic power systems, which worsens electric grid dispatching.
The work presented here provides, for the first time, a complete and new assessment of Reliability Centered Maintenance carried out using a failure mode and effect analysis approach to photovoltaic systems. We use a large volume of data derived from a database of real maintenance activities carried out by a multinational company. These data were interpreted by the opinions of experts with specialist experience in the installation, operation, and maintenance of photovoltaic power systems, from small to multi-megawatt size. The present work here has advantages over many previous studies since the information was derived from real experiences of photovoltaic systems which allowed for a more realistic risk analysis and, especially, this information was also used to revise the maintenance plan of photovoltaic installations and to optimize their effectiveness, concentrating on various failure modes which mostly affect production or which can be easily removed/reduced.
This article presents a perspective on the experimental and theoretical work to date on the efficiency of carrier multiplication (CM) in colloidal semiconductor nanocrystals (NCs). Early reports on ...CM in NCs suggested large CM efficiency enhancements. However, recent experiments have shown that CM in nanocrystalline samples is not significantly stronger, and often is weaker, than in the parent bulk when compared on an absolute photon energy basis. This finding is supported by theoretical consideration of the CM process and the competing intraband relaxation. We discuss the experimental artifacts that may have led to the apparently strong CM estimated in early reports. The finding of bulklike CM in NCs suggests that the main promise of quantum confinement is to boost the photovoltage at which carriers can be extracted. With this in mind, we discuss research directions that may result in effective use of CM in a solar cell.
An optimal PCE of 17.81% is achieved in LbL type OPVs by employing solvent additives for the layered optimization, which should be among the top level for all the LbL type binary OPVs. The ...performance improvement should be benefited from simultaneously improved JSC and FF due to the individually optimized photon harvesting and molecular arrangement, as well as suppressed charge recombination.
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•A PCE of 17.81% is achieved in the optimal LBL type OPVs.•The additives can act as photon harvesting reinforcer and morphology regulator.•The increased crystallize with additive can facilitate more swell matrix for exciton diffusion.
In this work, layer-by-layer (LbL) type OPVs are constructed with wide bandgap polymer PNTB6-Cl as donor and nonfullerene material BTP-4F-12 as acceptor. The layered optimization strategy is employed via separately incorporating the diphenyl ether (DPE) and 1,8-diiodooctane (DIO) into PNTB6-Cl chlorobenzene solution and BTP-4F-12 chloroform solution. A power conversion efficiency (PCE) of 17.81% was achieved from the optimal LbL type OPVs with two solvent additives, which should be among the top level for LBL type binary OPVs. The incorporation of DPE and DIO can separately induce more ordered PNTB6-Cl and BTP-4F-12 orientation, which should contribute to charge transport with suppressed charge recombination in active layers. Meanwhile, BTP-4F-12 crystallization is strongly increased with the incorporation of DIO, which should facilitate more swell matrix for exciton diffusion in active layers. Over 13% PCE improvement can be realized in LbL type OPVs by incorporating two additives, benefiting from simultaneously improved short circuit current density (JSC) of 26.89 mA cm−2 and fill factor (FF) of 75.79%. Meanwhile, the PCE of optimized LbL type OPVs is higher than that of 17.33% for the optimized OPVs with bulk-heterojunction (BHJ) configuration, which reveals that layered optimization strategy should be a promising approach to achieve highly efficient LbL type OPVs.
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