- A group of researchers in China has developed a prototype of a photovoltaic pavement for road applications.
“The system is not yet ready for commercial production, as it has only been tested indoors and no road has been paved to prove its long-term durability,” the research’s corresponding author, Xudong Zha, told pv magazine.
The pavement was built with a transparent resin-concrete material made with waste glass and unsaturated polyester resin, with the latter being used as cementing material, as well as a curing agent and accelerator. “The transparent resin-concrete completely encapsulates the solar panel module, forming a whole and increasing the stability of the structure,” the scientists claimed, referring to the mechanical stress that pavement PV systems have to endure when they come in contact with vehicles or persons.
The system was equipped with built-in amorphous silicon solar modules. The modules are built with 130x120mm solar cells and have a size of 150x150x2mm. Their rated power is 3W and the power conversion efficiency reaches 15.51%. The resin pouring body has an irradiance ratio of 88.3%, a brightness ratio of 88.2%, and an open-circuit ratio of 97.5%.
The compressive strength of the 100×100×25mm prototype was measured using a microcomputer-controlled electro-hydraulic servo pressure-testing machine and its optical properties were measured in a dark room.
The daily power generation of the solar pavement module was found to be 0.152 kWh/m2, which is about 16.28% of the original solar panel. The scientists specified that the low power-generation efficiency of the solar pavement module was due to the low solar irradiance of the testing location in Changsha, Central China, in November, as well as to the loss of light caused by the reflection of the module surface, the light loss through the transparent resin-concrete, and the heat released during resin curing, which may have had some effect on the solar panel.
The proposed system is said to achieve a levelized cost of energy of $0.175/kWh, which is claimed to make the solar pavement cost-effective compared to other types of solar pavement. “Although the investment cost of transparent resin-concrete solar pavement is higher than cement pavement and asphalt pavement in the early stage, its intangible economic, environmental influences and social benefits are considerable in the long run,” the academics concluded.
Their findings were presented in the study Preparation and performance study of solar pavement panel based on transparent Resin-Concrete, published in Sustainable Energy Technologies and Assessments.
Author: Emiliano Bellini
This article was originally published in pv magazine and is republished with permission.