@article{Bredemeier2023,

title = {Large-scale spatiotemporal calculation of photovoltaic capacity factors using ray tracing: A case study in urban environments},

author = {D Bredemeier and C Schinke and R Niepelt and R Brendel},

doi = {10.1002/pip.3756},

year  = {2024},

date = {2024-04-01},

urldate = {2023-11-29},

journal = {Progress in Photovoltaics: Research and Applications},

volume = {32},

issue = {4},

pages = {232-243},

abstract = {Photovoltaics (PVs) on building facades, either building-integrated or building-attached, offer a large energy yield potential especially in densely populated urban areas. Targeting this potential requires the availability of planning tools such as insolation forecasts. However, calculating the PV potential of facade surfaces in an urban environment is challenging. Complex time-dependent shadowing and light reflections must be considered. In this contribution, we present fast ray tracing calculations for insolation forecasts in large urban environments using clustering of Sun positions into typical days. We use our approach to determine time resolved PV capacity factors for rooftops and facades in a wide variety of environments, which is particularly useful for energy system analyses. The advantage of our approach is that the determined capacity factors for one geographic location can be easily extended to larger geographic regions. In this contribution, we perform calculations in three exemplary environments and extend the results globally. Especially for facade surfaces, we find that there is a pronounced intra-day and also seasonal distribution of PV potentials that strongly depends on the degree of latitude. The consideration of light reflections in our ray tracing approach causes an increase in calculated full load hours for facade surfaces between 10% and 25% for most geographical locations.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Min2024,

title = {Wet-Chemically Grown Interfacial Oxide for Passivating Contacts Fabricated With an Industrial Inline Processing System},

author = {B Min and P Noack and B Wattenberg and T Dippell and H Schulte-Huxel and R Peibst and R Brendel},

doi = {10.1109/JPHOTOV.2024.3352836},

year  = {2024},

date = {2024-03-01},

urldate = {2024-01-22},

journal = {IEEE Journal of Photovoltaics},

volume = {14},

issue = {2},

pages = {233-239},

abstract = {This article presents for the first time the application of wet-chemical interfacial oxide from an industrial inline processing system for poly-Si-based passivating contacts. An excellent passivation quality is achieved by creating an interfacial oxide with a very short exposure time of 90 s in ozonized water and by adjusting the annealing temperature in a tube furnace, resulting in surface recombination current densities of 4 fA/cm 2 and 1.2 fA/cm 2 before and after a hydrogenation step, respectively. Detailed electrical characterization reveals the interplay of in-diffusion of P into the wafer and hydrogenation step. Our investigation shows that the optimum annealing temperature can differ before and after the hydrogenation step. The developed wet-chemical interfacial oxide is successfully implemented in back junction solar cells on large-area gallium-doped p-type silicon wafers (156.75 × 156.75 mm 2 ) featuring a phosphorus-doped poly-Si-based passivating contact at the rear side. The best cell has an efficiency of 23.6% and an open-circuit voltage of 719 mV, independently confirmed by ISFH CalTeC in Germany. Our cost calculation shows a saving of up to 17.2% in capital expenditure, 5.2% p.a. in operating expense, and 9.0% in the footprint if the interfacial oxide is formed by an inline wet-chemical processing system instead of a plasma chamber.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Green2024,

title = {Solar cell efficiency tables (Version 63)},

author = {M A Green and E D Dunlop and M Yoshita and N Kopidakis and K Bothe and G Siefer and X Hao},

doi = {10.1002/pip.3750},

year  = {2024},

date = {2024-01-01},

urldate = {2024-01-01},

journal = {Progress in Photovoltaics: Research and Applications},

volume = {32},

number = {1},

pages = {3-13},

abstract = {Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July 2023 are reviewed.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Salomon2024,

title = {Assessment of the Required Maximum-Power-Point-Tracking Speed for Vehicle-Integrated Photovoltaics Based on Transient Irradiation Measurements and Dynamic Electrical Modeling},

author = {L Salomon and G Wetzel and J Krügener and R Peibst},

doi = {10.1002/solr.202300795},

year  = {2024},

date = {2024-01-01},

urldate = {2023-11-13},

journal = {Solar RRL},

volume = {8},

issue = {2},

pages = {2300795},

abstract = {Fast changing irradiation on vehicle-integrated photovoltaic (VIPV) modules may impose demanding requirements for maximum power point tracking (MPPT) to ensure high energy conversion efficiency. In this work, the results of simulations regarding the output and efficiency of an exemplary VIPV module under real-life irradiation conditions as measured with high time resolution are resulted. Herein, resistive as well as voltage source load is used as two idealized models of the MPPT. The simulations show that, in most cases, tracking with a resistive load at 1 Hz preserves above 90%rel of the convertible energy determined by the cell performances under given irradiance levels. With a voltage source load, these values do not undercut 97%rel at 0.1 Hz. Herein, it is also found that partial shading across the exemplary series connected module can reduce the converted energy in the range of 5–10%rel in relation to complete negligence of this effect.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Schulte-Huxel2024,

title = {Novel busbar design for screen-printed front side Al metallization of high-efficiency solar cell},

author = {H Schulte-Huxel and T Daschinger and B Min and T Brendemühl and R Brendel},

doi = {10.1016/j.solmat.2023.112601},

issn = {0927-0248},

year  = {2024},

date = {2024-01-01},

urldate = {2024-01-01},

journal = {Solar Energy Materials and Solar Cells},

volume = {264},

pages = {112601},

abstract = {The need to reduce the silver consumption for future global PV production requires novel approaches for cell metallization and module integration. A screen-printed aluminum cell metallization on the front side could contribute here, but requires a redesign of the solder pads and busbars. A compromise between shading and resistive losses is needed. We investigate the inclusion of Ag solder pads in high-aspect-ratio Al finger grids on the front side of p-type back junction solar cells featuring passivating polysilicon on oxide (POLO) contacts on the rear side. In order to determine the optimal geometric dimensions of the solder pads, we characterize the resistance at the interface between the Ag solder pads and the Al finger grid in dependence on the size of the overlap between the two paste. A contact resistance of 285 mΩ is determined for 200 μm-narrow Al busbars and small solder pads of 750 μm in length. This would require tens of solder pads per busbar for acceptable power losses below 0.5 % coming along with significant shading. Therefore, a new metallization design is developed. We use narrow Ag busbars with a widened intersection to the Al fingers in order to reduce the contact resistance caused by the Ag–Al alloy. Thereby, the shading losses of the solderable busbars and pads are less than 1.5 %.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Herz2023,

title = {Identify, analyse and mitigate—Quantification of technical risks in PV power systems},

author = {M Herz and G Friesen and U Jahn and M Koentges and S Lindig and D Moser},

doi = {10.1002/pip.3633},

year  = {2023},

date = {2023-12-01},

urldate = {2023-01-01},

journal = {Progress in Photovoltaics: Research and Applications},

volume = {31},

number = {12},

pages = {1285-1298},

abstract = {Technical risks are important criteria to consider when investing in new and existing PV installations. Quantitative knowledge of these risks is one of the key factors for the different stakeholders, such as asset managers, banks or project developers, to make reliable business decisions before and during the operation of their PV assets. Within the IEA PVPS Task 13 Expert Group, we aim to increase the knowledge on methodologies to assess technical risks and mitigation measures in terms of economic impact and effectiveness. The developed outline provides a reproducible and transparent technique to manage the complexity of risk analysis and processing in order to establish a common practice for professional risk assessment. Semi-quantitative and quantitative methodologies are introduced to assess technical risks in PV power systems and provide examples of common technical risks described and rated in the new created PV failure fact sheets (PVFS). Besides the PVFS based on expert knowledge and expert opinion, an update on the statistics of the PV failure degradation survey is given. With the knowledge acquired and data collected, the risk and cost–benefit analysis is demonstrated in a case study that shows methods for prioritising decisions from an economic perspective and provided important results for risk managing strategies.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}