Photovoltaic (PV) panels installed on building rooftops yield a positive influence on the thermal performance of the building due to the shading of the PV panels, decreasing cooling loads while causing a smaller increase in heating loads.
As the first type of the studies mentioned above, the shading effect of rooftop PV panels on energy consumption and thermal performance of buildings have been investigated in several studies. For instance, the effect of four different roofs was assessed on the building's thermal loads.
Can photovoltaic roofs save energy?
Finally, a quantitative method for evaluating the comprehensive potential for energy savings is proposed, considering the electricity generation gain of photovoltaic panels and the comprehensive energy-saving efficiency of photovoltaic roofs, which generates a total potential for energy savings rate of 61.06%.
How does a roof-added PV system affect energy consumption?
Using PV panels are considered one of the main strategies to generate electricity from sun exposure. Besides energy generation, a roof-added PV system affects the building's energy consumption due to its shading effect. Shading effects would differ depending on the roof's thermal properties, climate, and PV system design.
Zheng and Weng tested the potential mitigative effects of green roofs and photovoltaic systems on the increased building energy demand caused by climate change in Los Angeles County, California.
Do solar panels improve the efficiency of green roofs?
However, the efficiency improvement depends on the plant type of green roof (Abderrezek & Fathi, 2017). Jahanfar et al. have evaluated the shading effect of PV panels on green roof capacity for rainwater retention and vegetation growth.
Do rooftop photovoltaic panels reduce indoor heat gain?
Rooftop photovoltaic panels can serve as external shading devices on buildings, effectively reducing indoor heat gain caused by sunlight. This paper uses a numerical model to analyze rooftop photovoltaic panels' thermal conduction, convection, and radiation in hot summer areas as shading devices.