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Using sky-classification to improve the short-term prediction of irradiance with sky images and convolutional neural networks

Martinez Lopez, V.A. (author), van Urk, G.A. (author), Doodkorte, P.J.F. (author), Zeman, M. (author), Isabella, O. (author), Ziar, H. (author)

Clouds moving in front or away from the sun are the leading cause of irradiance variability. These variations have a repercussion on the electricity production of photovoltaic systems. Predicting such changes is essential for proper control of these systems and for maintaining grid stability. Images from the sky have proven to help with short...

journal article 2024

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Strategies for realizing high-efficiency silicon heterojunction solar cells

Zhao, Y. (author), Procel Moya, P.A. (author), Han, C. (author), Cao, L. (author), Yang, G. (author), Özkol, E. (author), Alcañiz, Alba (author), Kovačević, K. (author), Limodio, G. (author), Santbergen, R. (author), Smets, A.H.M. (author), Weeber, A.W. (author), Zeman, M. (author), Mazzarella, L. (author), Isabella, O. (author)

Silicon heterojunction (SHJ) solar cells have achieved a record efficiency of 26.81% in a front/back-contacted (FBC) configuration. Moreover, thanks to their advantageous high V_OC and good infrared response, SHJ solar cells can be further combined with wide bandgap perovskite cells forming tandem devices to enable efficiencies well...

journal article 2023

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A Comprehensive Workflow for High Resolution 3D Solar Photovoltaic Potential Mapping in Dense Urban Environment: A Case Study on Campus of Delft University of Technology

Zhou, Y. (author), Verkou, M.H. (author), Zeman, M. (author), Ziar, H. (author), Isabella, O. (author)

Photovoltaic (PV) technology is the most promising renewable energy source to be integrated on urban building surfaces. Modeling and simulating urban PV systems pose more challenges than the conventional ones installed in open field due to rich urban morphology. Herein, a comprehensive workflow to estimate urban solar PV potential is...

journal article 2021

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Strategy to mitigate the dipole interfacial states in (i)a-Si:H/MoOxpassivating contacts solar cells

Mazzarella, L. (author), Alcañiz Moya, A. (author), Kawa, Eliora (author), Procel Moya, P.A. (author), Zhao, Y. (author), Han, C. (author), Yang, G. (author), Zeman, M. (author), Isabella, O. (author)

Electrical simulations show that the dipole formed at (i)a-Si:H/MoOx interface can explain electrical performance degradation. We experimentally manipulate this interface by a plasma treatment (PT) to mitigate the dipole strength without harming the optical response. The optimal PT + MoOx stack results in strongly improved electrical...

conference paper 2020

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Realizing the Potential of RF-Sputtered Hydrogenated Fluorine-Doped Indium Oxide as an Electrode Material for Ultrathin SiO _x/Poly-Si Passivating Contacts

Han, C. (author), Yang, G. (author), Montes, Ana (author), Procel Moya, P.A. (author), Mazzarella, L. (author), Zhao, Y. (author), Eijt, S.W.H. (author), Schut, H. (author), Zhang, Xiaodan (author), Zeman, M. (author), Isabella, O. (author)

In high-efficiency silicon solar cells featuring carrier-selective passivating contacts based on ultrathin SiOx/poly-Si, the appropriate implementation of transparent conductive oxide (TCO) layers is of vital importance. Considerable deterioration in passivation quality occurs for thin poly-Si-based devices owing to the sputtering damage...

journal article 2020

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Constructing accurate equivalent electrical circuit models of lithium iron phosphate and lead-acid battery cells for solar home system applications

Yu, Y. (author), Narayan, N.S. (author), Vega Garita, V.E. (author), Popovic, J. (author), Qin, Z. (author), Wagemaker, M. (author), Bauer, P. (author), Zeman, M. (author)

The past few years have seen strong growth of solar-based off-grid energy solutions such as Solar Home Systems (SHS) as a means to ameliorate the grave problem of energy poverty. Battery storage is an essential component of SHS. An accurate battery model can play a vital role in SHS design. Knowing the dynamic behaviour of the battery is...

journal article 2018

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Size control, quantum confinement, and oxidation kinetics of silicon nanocrystals synthesized at a high rate by expanding thermal plasma

Han, L. (author), Zeman, M. (author), Smets, A.H.M. (author)

The growth mechanism of silicon nanocrystals (Si NCs) synthesized at a high rate by means of expanding thermal plasma chemical vapor deposition technique are studied in this letter. A bimodal Gaussian size distribution is revealed from the high-resolution transmission electron microscopy images, and routes to reduce the unwanted large Si NCs are...

journal article 2015

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Raman Study of Laser Induced Heating Effects in Free-Standing Silicon Nanocrystals

Han, L. (author), Zeman, M. (author), Smets, A.H.M. (author)

This paper demonstrates that free-standing silicon nanocrystals (Si NCs) have significantly different thermal conductivity properties compared to Si NCs embedded in a host matrix. The temperatures of Si NCs under laser illumination have been determined by measuring the ratio of the Anti-Stokes to Stokes intensities of the first order Si–Si...

journal article 2015

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Opto-electrical approaches for high efficiency and ultra-thin c-Si solar cells

Ingenito, A. (author), Isabella, O. (author), Zeman, M. (author)

The need for cost reduction requires using less raw material and cost-effective processes without sacrificing the conversion efficiency. For keeping high the generated photo-current, an advanced light trapping scheme for ultra-thin silicon wafers is here proposed, exhibiting absorptances up to 99% of 4n2 classical absorption limit for wafer...

conference paper 2014

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Wet-chemical Treatment for Improved Surface Passivation of Textured Silicon Heterojunction Solar Cells

Deligiannis, D. (author), Alivizatos, S. (author), Ingenito, A. (author), Zhang, D. (author), Van Sebille, M. (author), Van Swaaij, R.A.C.M.M. (author), Zeman, M. (author)

Silicon heterojunction (SHJ) solar cells constantly gain more attention due to their low cost and relatively high efficiency. An important aspect of these solar cells is the incorporation of intrinsic hydrogenated amorphous silicon (a-Si:H) layers at each side of the c-Si wafer, which has increased the efficiency potential due to the excellent...

journal article 2014

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Optimized back Reflectors for Rear Diffused c-Si Solar Cells

Ingenito, A. (author), Ortiz Lizcano, J.C. (author), Luxembourg, S.L. (author), Santbergen, R. (author), Weeber, A. (author), Isabella, O. (author), Zeman, M. (author)

At present, research in c-Si solar cells is focused on increasing the efficiency while reducing the amount of used materials. Since silicon wafer and metal contribute up to 50% to the cost of a module, it is crucial to reduce the amount of these materials to fabricate cost-effective modules. In particular, for reducing the consumption of metal,...

journal article 2014

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Quantum confinement and band offsets in amorphous silicon quantum wells

Jarolimek, K. (author), De Groot, R.A. (author), De Wijs, G.A. (author), Zeman, M. (author)

Quantum wells (QWs) are nanostructures consisting of alternating layers of a low and high band-gap semiconductor. The band gap of QWs can be tuned by changing the thickness of the low band-gap layer, due to quantum confinement effects. Although this principle is well established for crystalline materials, there is still controversy for QWs...

journal article 2014

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Quadruple-junction thin-film silicon-based solar cells with high open-circuit voltage

Si, F.T. (author), Kim, D. (author), Santbergen, R. (author), Tan, H. (author), Van Swaaij, R.A.C.M.M. (author), Smets, A.H.M. (author), Isabella, O. (author), Zeman, M. (author)

journal article 2014

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Enhancing the driving field for plasmonic nanoparticles in thin-film solar cells

Santbergen, R. (author), Hairen, T. (author), Zeman, M. (author), Smets, A.H.M. (author)

The scattering cross-section of a plasmonic nanoparticle is proportional to the intensity of the electric field that drives the plasmon resonance. In this work we determine the driving field pattern throughout a complete thin-film silicon solar cell. Our simulations reveal that by tuning of the thicknesses of silicon and transparent conductive...

journal article 2014

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Micro-textures for efficient light trapping and improved electrical performance in thin-film nanocrystalline silicon solar cells

Tan, H. (author), Psomadaki, E. (author), Isabella, O. (author), Fischer, M. (author), Babal, P. (author), Vasudevan, R.A. (author), Zeman, M. (author), Smets, A.H.M. (author)

journal article 2013

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Plasmonic silicon solar cells: Impact of material quality and geometry

Pahud, C. (author), Isabella, O. (author), Naqavi, A. (author), Haug, F.J. (author), Zeman, M. (author), Herzig, H.P. (author), Ballif, C. (author)

We study n-i-p amorphous silicon solar cells with light-scattering nanoparticles in the back reflector. In one configuration, the particles are fully embedded in the zinc oxide buffer layer; In a second configuration, the particles are placed between the buffer layer and the flat back electrode. We use stencil lithography to produce the same...

journal article 2013

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Designing optimized nano textures for thin-film silicon solar cells

Jäger, K. (author), Fischer, M. (author), Van Swaaij, R.A.C.M.M. (author), Zeman, M. (author)

Thin-film silicon solar cells (TFSSC), which can be manufactured from abundant materials solely, contain nano-textured interfaces that scatter the incident light. We present an approximate very fast algorithm that allows optimizing the surface morphology of two-dimensional nano-textured interfaces. Optimized nano-textures scatter the light...

journal article 2013

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Improved light trapping in microcrystalline silicon solar cells by plasmonic back reflector with broad angular scattering and low parasitic absorption

Tan, H. (author), Sivec, L. (author), Yan, B. (author), Santbergen, R. (author), Zeman, M. (author), Smets, A.H.M. (author)

We show experimentally that the photocurrent of thin-film hydrogenated microcrystalline silicon (?c-Si:H) solar cells can be enhanced by 4.5?mA/cm2 with a plasmonic back reflector (BR). The light trapping performance is improved using plasmonic BR with broader angular scattering and lower parasitic absorption loss through tuning the size of...

journal article 2013

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Dangling-bond defect in a-Si:H: Characterization of network and strain effects by first-principles calculation of the EPR parameters

Pfanner, G. (author), Freysoldt, C. (author), Neugebauer, J. (author), Inam, F. (author), Drabold, D. (author), Jarolimek, K. (author), Zeman, M. (author)

The performance of hydrogenated amorphous silicon (a-Si:H) solar cells is severely affected by the light-induced formation of metastable defects in the material (Staebler-Wronski effect). The common notion is that the dangling-bond (db) defect, a threefold coordinated silicon atom, plays a key role in the underlying mechanisms. To support the...

journal article 2013

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Optical model for multilayer structures with coherent, partly coherent and incoherent layers

Santbergen, R. (author), Smets, A.H.M. (author), Zeman, M. (author)

We present a novel approach for modeling the reflectance, transmittance and absorption depth profile of thin-film multilayer structures such as solar cells. Our model is based on the net-radiation method adapted for coherent calculations and is highly flexible while using a simple algorithm. We demonstrate that as a result arbitrary multilayer...

journal article 2013