The impact of height installation on the performance of PV panels integrated into a green roof in tropical conditions

Abstract

This paper presents a study on the effect of the height installation of PV panels in a green roof integrated photovoltaic system (GRIPV) considering warm and humid climate conditions. According to recent work, there is mutual benefit between these two applications in temperate conditions. However, it is necessary to study this interaction in tropical conditions and to establish the significance of height as a factor of installation. Therefore, an experiment was designed using three PV panels of 250 W in portrait configuration with 10° of inclination; each PV panel uses a micro-inverter. The monitoring system can gather data such as ambient temperature, PV panel temperatures, solar radiation and electrical variables. The green roof used (440 m 2 ) is located on the Electrical Engineering Building of Universidad Industrial de Santander (Colombia), where the latitude is +7.1° and the ambient temperature varies between 24°C and 30°C during daily sun-time (6 am and 6 pm), while the relative humidity fluctuates between 60% and 90%. The experiment considers two height installations (50 cm and 75 cm) for both types of roof -black and green -for three weeks. According to the results, the lower height installation and the green roof increases the power output by 2.0% and 1.0%, respectively and the combined effect is nearly 2.8%.

Modeling the Effect of Green Roof Systems and Photovoltaic Panels for Building Energy Savings to Mitigate Climate Change

“…In addition, the energy-saving ability of green roofs did exhibit seasonality. The above findings agree with the results of previous studies [19,20,28,36,41]. However, this study further found that green roofs have different energy-saving abilities on different types of buildings with different technologies, which has received very little attention in previous studies.…”

“…However, an increase in soil thickness will also increase the weight of the green roof, which may exceed the load-bearing capacity of some building roofs. In addition, the distance between PV and green roofs, which can affect PV-power production [39][40][41], cannot be set up using the current version of EnergyPlus. Therefore, this study followed the settings of Sailor [20], which were based on validated data from two monitored buildings with green roofs at Portland State University, Oregon, instead of applied the optimal settings.…”

“…However, no evidence of this effect can be found if the PV installation heights were greater than 100 cm [40]. Osma et al indicated that PV system with separation height of 0.5 m was higher when compared with 0.75 m in their experimental site in Columbia [39,41]. Scherba et al indicated that the replacement of a traditional black membrane roof with a PV-green roof would reduce the total sensible flux by 50% [34].…”

Modeling the Effect of Green Roofs for Building Energy Savings and Air Pollution Reduction in Shanghai

“…This method can be further developed if more datasets, such as air pollutant monitoring data, are available. The dataset of the solar potential of individual roofs will also be helpful, as the integration of green roofs with solar panels can be beneficial for each other [65,66]. The city government can identify the most suitable buildings for green roof installation with the information on the actual amount of air pollution reduction through both direct (absorption) and indirect (energy savings through green roofs and solar panels) ways.…”