Building Energy Modeling and Life Cycle Assessment of Semi-Transparent Photovoltaic Windows

Author

• Bahareh Pourhosseini Akbarieh, Portland State UniversityFollow

Sponsor

Portland State University. Department of Mechanical and Materials Engineering

First Advisor

Ilke Celik

Term of Graduation

Summer 2026

Date of Publication

8-25-2026

Document Type

Thesis

Degree Name

Master of Science (M.S.) in Mechanical Engineering

Department

Mechanical and Materials Engineering

Language

English

Subjects

Building energy simulation, Building-integrated photovoltaics (BIPV), Energy saving, Global warming potential (GWP), Life cycle assessment, Semi-transparent photovoltaics (STPV)

Physical Description

1 online resource (vii, 72 pages)

Abstract

Semi-transparent photovoltaics (STPVs) are promising building-integrated technologies that can improve building energy performance while generating electricity and transmitting daylight. This study evaluates four STPV technologies with a consistent 20% average visible transmittance (AVT): a-Si, thin CdTe, perovskite, and organic. The systems were integrated into a reference medium office building with a 60% window-to-wall ratio in Los Angeles, Portland, Denver, and Baltimore. Optical properties were calculated using the transfer matrix method and incorporated into OpenStudio, while annual electricity generation was calculated using HelioScope. Life-cycle indicators, including global warming potential (GWP), energy payback time (EPBT), and net energy benefit (NEB) over a 30-year lifetime, were evaluated using the Ecoinvent database. STPV integration reduced cooling energy consumption by an average of 37%, while heating-energy impacts were smaller and climate-dependent, ranging from a 7% reduction to a 18% increase. The combined effects on building energy demand and on-site electricity generation resulted in annual energy savings of 17–37 kWh m^-2 yr^-1, with the highest savings for perovskite STPV in Los Angeles. Organic STPV had the lowest manufacturing-stage GWP (~29 kg CO₂-eq m^-2), while the other technologies showed comparable impacts (41–45 kg CO₂-eq m^-2). At the building level, STPV integration reduced use-phase GWP by up to 79%, with the largest reductions achieved by perovskite STPV. The normalized NEB values ranged from 4.56 to 9.52 GJ-eq m^-2 building, with the maximum achieved by perovskite STPV in Los Angeles. These energy benefits translated into EPBT of 65 to 466 days, highlighting the favorable life-cycle energy performance of STPV-integrated buildings.

Rights

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Comments

This study was partially supported by the U.S. National Science Foundation under Grants #2350522 and #2403520.

Persistent Identifier

https://archives.pdx.edu/ds/psu/45122

Recommended Citation

Pourhosseini Akbarieh, Bahareh, "Building Energy Modeling and Life Cycle Assessment of Semi-Transparent Photovoltaic Windows" (2026). Dissertations and Theses. Paper 7193.