- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Effects of a defected GaP/Si interface on a Si heterojunction interdigitated back contact (IBC) solar cell
摘要: Analyses have shown that electric vehicle (EV) loads may considerably affect the secondary service voltage quality. One of the ways to mitigate voltage drop concerns is to use a time-of-use (TOU) pricing scheme. A TOU pricing scheme utilizes the off-peak generation for EV charging, thus deferring any immediate grid upgrade and improving the grid sustainability. This paper evaluates various aspects of EV charging under a TOU schedule, with off-peak rates starting at hours ranging from 8 P.M. to 3 A.M. The study is conducted using an actual residential distribution circuit. A best practical time to begin the off-peak rates is determined so that the effects of EV charging on the secondary service voltages are minimized while ensuring that EVs are fully charged by 7 A.M., thus maximizing both grid and customer benefits. The analysis suggests that the best time to begin off-peak rates is between 11 P.M. and 12 A.M. Furthermore, the analysis also suggests that setting up TOU off-peak rates at the latter half of the peak load demand, for example, at 8 P.M., is detrimental to the distribution circuit voltage quality. The result indicates that the existing utility TOU scheme may exacerbate voltage drop problems due to EV load charging.
关键词: electric vehicle (EV),Distribution system,time-of-use (TOU) pricing,electricity market
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Evaluating the Impact of and Solutions to Light-induced Degradation in Silicon Heterojunction Solar Cells
摘要: Analyses have shown that electric vehicle (EV) loads may considerably affect the secondary service voltage quality. One of the ways to mitigate voltage drop concerns is to use a time-of-use (TOU) pricing scheme. A TOU pricing scheme utilizes the off-peak generation for EV charging, thus deferring any immediate grid upgrade and improving the grid sustainability. This paper evaluates various aspects of EV charging under a TOU schedule, with off-peak rates starting at hours ranging from 8 P.M. to 3 A.M. The study is conducted using an actual residential distribution circuit. A best practical time to begin the off-peak rates is determined so that the effects of EV charging on the secondary service voltages are minimized while ensuring that EVs are fully charged by 7 A.M., thus maximizing both grid and customer bene?ts. The analysis suggests that the best time to begin off-peak rates is between 11 P.M. and 12 A.M. Furthermore, the analysis also suggests that setting up TOU off-peak rates at the latter half of the peak load demand, for example, at 8 P.M., is detrimental to the distribution circuit voltage quality. The result indicates that the existing utility TOU scheme may exacerbate voltage drop problems due to EV load charging.
关键词: electricity market,time-of-use (TOU) pricing,Distribution system,electric vehicle (EV)
更新于2025-09-19 17:13:59
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Artificial neural network based assessment of grid-connected photovoltaic thermal systems in heating dominated regions of Iran
摘要: In this paper, an artificial neural network (ANN) is developed to assess hybrid photovoltaic thermal (PVT) systems for grid-connected (GC) electricity generation, space heating and domestic hot water providing in heating dominated regions of Iran. To do so, monthly and annual performance of a 5 kWp GCPVT system is simulated for a single-family house. The simulation results show that the GCPVT system is very promising whereas the annual yield factor varies from 1506 kWh/kWp to 1891 kWh/kWp. Also, an appropriate solar fractions for covering hot water are achieved in a range from 74.5% to 49.4%. A multilayered perceptron feed-forward neural network which is trained by Levenberg-Marquardt algorithm is used to predict AC electrical energy and solar thermal output of the GCPVT system. The developed ANN is based on global horizontal irradiance, ambient temperature, ambient relative humidity and wind speed as inputs. The proposed configuration of ANN presents a high accuracy in predicting output energy of the GCPVT system according to minimum mean square error and maximum correlation coefficient. Analysis of variance is performed to determine the significant control parameters influencing the output energy of the GCPVT system.
关键词: Solar heating,AC electricity,Grid-connected PVT,Artificial neural network,Performance assessment
更新于2025-09-19 17:13:59
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[IEEE 2017 IEEE 44th Photovoltaic Specialists Conference (PVSC) - Washington, DC (2017.6.25-2017.6.30)] 2017 IEEE 44th Photovoltaic Specialist Conference (PVSC) - Industry relevant RIE texturing for mc-Si diamond wire or Direct Wafer?? product: optimized reflectivity, uniformity, and throughput
摘要: Presently, America’s average electrical power consumption is ~1.3 kW/p; in the world as a whole, it is ~0.33 kW/p. If, for 2050, a world goal of 1 kW/p is adopted, this implies an average electric power draw of 1 GW for each population cohort of 1 000 000 residents; and the Earth will have ~10 000 such cohorts. Multi-hour outages are already common; demand peaks daily; and renewable generation is intermittent. Hence, as a hedge against rare supply failures, each cohort would profit from local backup storage of electricity/energy in the order of 1–2 GWd. For comparison, the biggest electrochemical storage scheme yet seriously proposed will contain ~240 MWh, while most of the largest pumped hydro storage reservoirs are <50 GWh. In approximately 50 years, when fossil fuels have become scarce, we should already have constructed this bulk storage. This review argues that the principal contenders for the storage of electricity in bulk are: 1) electrochemical storage in flow batteries; 2) chemical storage in agents, such as ammonia, hydrogen, methanol, or light hydrocarbons; 3) compressed air energy storage; and 4) underground pumped hydro. Finally, it will argue that not one of these four contenders has yet been built, tested, and perfected, while virtually none of the needed storage capacity exists today.
关键词: exhaustion of fossil fuels,intermittency challenge,massive electricity storage,underground pumped hydro,Energy storage
更新于2025-09-19 17:13:59
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[IEEE 2019 4th International Conference on Mechanical, Control and Computer Engineering (ICMCCE) - Hohhot, China (2019.10.24-2019.10.26)] 2019 4th International Conference on Mechanical, Control and Computer Engineering (ICMCCE) - Video Based Fire Detection in Photovoltaic System
摘要: This paper presents a novel energy-management method for a microgrid that includes renewable energy, diesel generators, battery storage, and various loads. We assume that the microgrid takes part in a pool market and responds actively to the electricity price to maximize its profit by scheduling its controllable resources. To address various uncertainties, a risk-constrained scenario-based stochastic programming framework is proposed using the conditional value at risk method. The designed model is solved by two levels of stochastic optimization methods. One level of optimization is to submit optimal hourly bids to the day-ahead market under the forecast data. The other level of optimization is to determine the optimal scheduling using the scenario-based stochastic data of the uncertain resources. The proposed energy management system is not only beneficial for the microgrid and customers, but also applies the microgrid aggregator and virtual power plant. The results are shown to prove the validity of the proposed framework.
关键词: energy management,Controllable load,stochastic optimization,microgrid,risk management,smart grid,renewable energy,electricity market
更新于2025-09-19 17:13:59
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Qualitative and quantitative risk assessment of expanding photovoltaics in the Netherlands
摘要: Expanding photovoltaics (PV) is important for reaching Dutch renewable energy and climate targets. In this paper, we assess risks of scaling up PV in the Dutch electricity sector and economy. With a computable general equilibrium model setup to analyse scenarios until 2050, we show that increasing PV shares initially lead to higher costs of electricity supply and thus retail prices. Until 2025, large storage investments will be required, leading to lower consumption possibilities presenting a critical barrier to initiate PV expansion. However, from 2025 onwards PV installation costs are expected to become competitive to wind power, leading to lower costs of electricity supply and electricity retail prices, with positive macroeconomic effects. Overall, we find positive long-term effects of PV expansion on GDP, welfare and employment from 2025 until mid-century. With stakeholders we then investigate system-level obstacles for PV expansion in the Netherlands. A key observation is that inconsistent policy mixes are an obstacle to successful PV implementation.
关键词: Intermittent,Photovoltaics,Stakeholder engagement,CGE,Risks,Electricity
更新于2025-09-16 10:30:52
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Supplemental intracanopy far-red radiation to red LED light improves fruit quality attributes of greenhouse tomatoes
摘要: Off-season greenhouse tomatoes have a poor reputation relative to their in-season, field-grown counterparts. Previously, we reported that supplemental intracanopy far-red (700–800 nm, FR) radiation in addition to red (600–700 nm, R) light with light-emitting diodes (LEDs) significantly decreased fruit water content compared to R LEDs alone and high-pressure sodium (HPS) lamps, the most common supplemental lighting used in commercial greenhouses. We hypothesize that supplemental R + FR LEDs during production improves fruit quality attributes (i.e., physicochemical properties, mineral concentrations, and sensory properties) in greenhouse tomatoes compared to R LEDs and HPS lamps. Both intracanopy LED lights increased fruit yield and biomass compared to HPS lamps. R LEDs increased dry matter ratio and improved overall physicochemical proprieties such as total soluble solids (TSS), titratable acidity (TA), and pH; however, R + FR LEDs had more significant effects on all measured attributes than did R LEDs. Similarly, R LEDs increased potassium, magnesium, and calcium content in whole fruit by 30, 74, and 40% compared to HPS lamps, and the addition of FR to R LEDs further increased sodium (Na) content and concentration. Consumer sensory panelists rated higher for sensory attributes (aroma, sweetness, acidity, and texture) of R + FR LED-supplemented tomatoes on a hedonic scale compared to R LED-supplemented ones. Importantly, HPS lamp-supplemented tomatoes had the least desirable quality attributes even when compared at the same ripe stage as LED-supplemented ones. Energy use efficiency (EUE) was not different between R + FR LEDs and R LEDs, which was 5 times higher than that of HPS lamps. Our results demonstrate for the first time that fruit quality attributes of greenhouse tomatoes can be improved by supplemental intracanopy lighting with R + FR LEDs to a degree that consumer panelists could perceive the differences. Therefore, we conclude that supplemental R + FR LEDs is indispensable for improving fruit quality of greenhouse tomatoes during off-season production.
关键词: Sensory evaluation,Electricity consumption,Hydroponics,Mineral nutrients,Solanum lycopersicum,Chromaticity,Intracanopy lighting
更新于2025-09-16 10:30:52
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Photovoltaic performance of one axis multiple-position sun-tracked PV panels
摘要: In this article, the photovoltaic performance of one-axis multiple-positions sun-tracked photovoltaic panels (MP-PV) is investigated based on solar geometry and dependence of photovoltaic conversion efficiency on the incident angle (IA) of solar rays on PV panels. For such PV system, the azimuth angle (AZA) of PV panels is daily adjusted several times (M) from eastward in the morning to westward in the afternoon by rotating PV panels about inclined north-south axis (INSA) to ensure the projected incident angle (PIA) of solar rays on the plane perpendicular to INSA is always less than the specified angle θa. Results show that, the annual electricity generation (AEG) of MP-PV increases with the increase of M, but such increase is not noticeable when M>5. For MP-PV with the tilt-angle (β) of INSA being yearly fixed (1T-MP-PV), the optimal θa of 3P-,5P- and 7P-PV for maximizing AEG are respectively 24o, 15o and 11.5o, and their AEGs are respectively about 92%, 94% and 95% of that from similar 2-axis tracked PV panels (2A-PV). Whereas for MP-PV with the β being yearly adjusted four times at three tilts (3T-MP-PV), the optimal θa of 3P-, 5P- and 7P-PV are respectively about 22.5o, 14.5o and 11o, and the Pa are respectively about 96%, 98% and 99% of that of similar 2A-PV systems.
关键词: photovoltaic conversion efficiency,azimuth angle,annual electricity generation,solar geometry,sun-tracked PV panels,incident angle,photovoltaic performance
更新于2025-09-16 10:30:52
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A comparison of arrangements for increasing self-consumption and maximising the value of distributed photovoltaics on apartment buildings
摘要: As subsidised feed-in-tariffs for distributed photovoltaic (PV) generation are reduced or abolished in many jurisdictions, there is growing interest in increasing self-consumption to realise greater value from rooftop PV generation. However, deployment of PV on apartment buildings lags behind other residential deployment despite the potential advantages of load aggregation. We present a study of electricity and financial flows in ten ‘virtual’ Australian apartment buildings under a range of technical implementations and financial arrangements, using real load profiles and simulated generation profiles. Aggregation of diverse household and shared loads, either through an embedded network or ‘behind the meter’ of individual dwellings, can increase self-sufficiency and self-consumption of on-site generation compared to separate systems supplying common property or individual apartments. While embedded networks can enable access to more beneficial retail arrangements, behind the meter solutions may allow residents to avoid regulatory complexities and additional costs. The relative benefits of each arrangement are dependent on building characteristics and financial settings.
关键词: Load aggregation,Apartments,Self-consumption,Embedded network,Residential electricity,Photovoltaics
更新于2025-09-16 10:30:52
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Investigation on Industrial Screen-Printed Aluminum Point Contact and Its Application in n-PERT Rear Junction Solar Cells
摘要: As compared with the traditional back surface field (BSF) solar cells, the n-type passivated emitter rear and totally diffused rear-junction (n-PERT-RJ) solar cells have much lower carrier recombination losses on their rear sides. In order to obtain more benefits (higher open-circuit voltages) from the currently passivated rear sides, the implementation of the point contact concept is an intuitive solution. In this article, we present industrial screen-printed point contacts that are metallized with aluminum (Al) pastes containing silicon additives (Si-add). To understand the impacts of the Si-add on the performance our n-PERT-RJ solar cells, the detailed loss analysis on the open-circuit voltage (VOC), short-circuit current density (JSC), and fill factor are performed separately. The effect of Si-add and pitch of laser contact openings (LCO) on the point contact characteristics are also investigated. In the last part, we introduce an innovative “point-line” contact concept on the rear side, which is composed of dot-shaped LCO and Al metal finger design, resulting in an n-PERT-RJ solar cell to reach VOC of 692 mV and peak efficiency of 22%. The 60% bifaciality of the device opens the way for an additional power output on module level, which further reduces the levelized cost of electricity. These features make the rear-side point contact design more flexible to be applied in industrial mass production.
关键词: laser contact opening (LCO),levelized cost of electricity,Aluminum (Al) paste,n-type passivated emitter rear and totally diffused (n-PERT),bifaciality,silicon solar cell,industrial,point contacts,screen printed,n-type,rear junction
更新于2025-09-16 10:30:52