Title: UV‐induced degradation of high‐efficiency silicon PV modules with different cell architectures

Abstract

Degradation from ultraviolet (UV) radiation has become prevalent in the front of solar cells due to the introduction of UV-transmitting encapsulants in photovoltaic (PV) module construction. Here, we examine UV-induced degradation (UVID) in various commercial, unencapsulated crystalline silicon cell technologies, including bifacial silicon heterojunction (HJ), interdigitated back contact (IBC), passivated emitter and rear contact (PERC), and passivated emitter rear totally diffused (PERT) solar cells. We performed UV exposure tests using UVA-340 fluorescent lamps at 1.24 W·m^–2 (at 340 nm) and 45°C through 4.02 MJ·m^–2 (2000 h). Our results showed that modern cell architectures are more vulnerable to UVID, leading to a significant power decrease (–3.6% on average; –11.8% maximum) compared with the conventional aluminum back surface field (Al-BSF) cells (<–1% on average). The power degradation is largely caused by the decrease in short-circuit current and open-circuit voltage. A greater power decrease is observed in bifacial cells with rear-side exposure compared with those with front-side exposure, indicating that the rear side is more susceptible to UV damage. Secondary ion mass spectroscopy (SIMS) confirmed an increase in hydrogen concentration near the Si/passivation interface in HJ and IBC cells after UV exposure; the excess of hydrogen could result in hydrogen-induced degradation and subsequentlymore » cause higher recombination losses. Additionally, surface oxidation and hot-carrier damage were identified in PERT cells. Using a spectral-based analysis, we obtained an acceleration factor of 5× between unpackaged cells (containing a silicon nitride antireflective coating on the front) in the UV test and an encapsulated module (with the front glass and encapsulant blocking 90% of the UV at 294 nm and 353 nm, respectively) in outdoor conditions. From the analytical calculations, we show that a UV-blocking encapsulant can reduce UV transmission in the module by an additional factor of ~50.« less

Authors:

Sinha, Archana  ^[1];

• Search DOE PAGES for author "Sinha, Archana"
• Search DOE PAGES for ORCID "0000-0001-5272-1123"

Qian, Jiadong ^[2]; Moffitt, Stephanie L. ^[1]; Hurst, Katherine ^[2]; Terwilliger, Kent ^[2]; Miller, David C.  ^[2];

• Search DOE PAGES for author "Miller, David C."
• Search DOE PAGES for ORCID "0000-0002-4698-5277"

Schelhas, Laura T.  ^[2];

• Search DOE PAGES for author "Schelhas, Laura T."
• Search DOE PAGES for ORCID "0000-0003-2299-1864"

Hacke, Peter  ^[2]

• Search DOE PAGES for author "Hacke, Peter"
• Search DOE PAGES for ORCID "0000-0003-4850-0947"

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+ Show Author Affiliations

1. SLAC National Accelerator Laboratory Menlo Park California USA
2. National Renewable Energy Laboratory Golden Colorado USA

Publication Date:

Thu Jul 07 00:00:00 EDT 2022

Research Org.:

National Renewable Energy Laboratory (NREL), Golden, CO (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)

Sponsoring Org.:

USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office; USDOE Office of Science (SC)

OSTI Identifier:

1875203

Alternate Identifier(s):

OSTI ID: 1877600; OSTI ID: 1885574; OSTI ID: 1889840; OSTI ID: 1902555

Report Number(s):

NREL/JA-5900-81471
Journal ID: ISSN 1062-7995

Grant/Contract Number:  

32509; DE‐AC36‐08GO28308; AC02-76SF00515; AC36-08GO28308

Resource Type:

Published Article

Journal Name:

Progress in Photovoltaics

Additional Journal Information:

Journal Name: Progress in Photovoltaics Journal Volume: 31 Journal Issue: 1; Journal ID: ISSN 1062-7995

Publisher:

Wiley Blackwell (John Wiley & Sons)

Country of Publication:

United Kingdom

Language:

English

Subject:

14 SOLAR ENERGY; bifacial heterojunction; PV modules; UV-induced degradation; UVID