Abstract
Purpose: The Cape Town City energy goal for 2020 included significant small-scale embedded
generation units, primarily in the form of a photovoltaic (PV) system on rooftops in the commercial
sector. However, severe storms (synoptic or convective) subject the photovoltaic panels to harsh
wind conditions, lift forces and drag.
Methodology: This study simulates the wind effects on flat roof-mounted photovoltaic panels at
various panel tilt angles (25° to 35°) and various wind directions (0° to 180°). Furthermore, a wind
speed magnitude of 120 km/h is used.
Findings/Results: The results show that flow structures are significantly affected by the panel tilt,
wind direction and wind speed. A higher tilt angle induces more substantial vortex fluctuations
and higher velocity zones shedding frequency. The net pressure of the solar panel increased with
the higher panel tilt angle.
Conclusions: Based on the results and insights, it was concluded that attention should be paid to
roofs with lower heights as they cause remarkable variation of wind pressure on the photovoltaic
panels. The photovoltaic panels fixed at a tilt between 25 ° and 35 ° are recommended.
Contribution to knowledge:
Since the implementation of photovoltaic panels in the construction industry in the early 90s in
Japan, most researchers have shown interest in attempting to more fully understand these panels'
behaviour when subjected to harsh wind and storm conditions. Researchers have made a concerted
effort to invest in this need regarding investigations and the number of published papers. However,
despite the available literature demonstrating the advantages that solar panels offer, the structural
reliability of the panels by the South African construction industry and new homeowners is still
relatively minimal. This is due to the lack of specifications and limitations in understanding its
structural behaviour adapted to local conditions. This work contributes to the current knowledge
about flat roof mounted photovoltaic panels by providing information about storm interaction and
its effects. Finally, this work notes that using photovoltaic panels provides a clean, reliable alternative to fuel
and coal-based power generation systems, often associated with pollution and depletion of nonrenewable
sources. Although the benefits related to the wide usage of solar panels on roof tops
outweighs the implementation costs as well as proven technical attributes and safety capability of
the enhanced mounting frames, there are still much work to be done by policymakers to support
the establishment of tilted solar panels among the alternatives to solve the current energy crises.
Keywords: Photovoltaic panels, wind, storm and rooftops.