Solar Pavement Research Articles

Structural optimization and performance testing of concentrated photovoltaic panels for pavement

Solar pavement can convert sunlight shining on the pavement surface into clean electricity through photovoltaic panels, thereby transforming the energy structure of road transportation. In order to balance the light transmittance and anti-skid resistance of the solar pavement surface, this study proposed a concentrated photovoltaic panel (CPP) structure for pavement. The panel structure was optimized, and a laboratory model was developed. The mechanical properties and durability of the panel were tested by the multi-functional material test system (MTS) and the model mobile load simulator 3 (MMLS3). Furthermore, the electrical performance was evaluated by an outdoor test, followed by an economic evaluation. The results show that the optimal structural dimensions of the CPP for pavement are 540 mm long × 540 mm in length × 144.62 mm in thickness. The maximum flexural tensile strength of its anti-skid concentrated panel is 61.67 MPa, satisfying the requirements of the traffic load. After 1.35 million cycles of loading, the surface of the anti-skid concentrated panel is free of cracks and deformation and has no obvious wear, exhibiting good transmittance durability and excellent wear resistance. In addition, the overall structure of the panel counteracts the light loss effect of the material and improves the light concentration performance, providing a gain effect on the power generation of the panel, especially in the case of high irradiance. The return on investment (ROI) of CPP for pavement is 54.42%, with cost recovery in 9.87 years. The levelized cost of energy is 0.67 CNY/kWh, indicating significant economic benefits. At the same time, 1539.3 kg/m2 of CO2 emissions can be avoided during the operation cycle, and the environmental benefits are also considerable. This study can provide a reference for the promotion and application of photovoltaic power generation technology in road engineering.

Pioneering the Path to Sustainable Construction: Unveiling the Triumphs and Trajectories of Innovative Materials

In the dynamic realm of sustainable construction, innovation in materials is a compelling strategy to overcome the limitations of conventional products. This study delves into two extraordinary case studies - Rammed Earth and Solar Pavement - to uncover their successes and potential impact. It navigates through a landscape of innovative materials, from research to real-world implementations, focusing on materials that harness nature's gifts and promote eco-consciousness, reducing carbon footprints. This investigation employs a comprehensive methodology, analysing scholarly manifestos, journal chronicles, historical documents, and credible references. It explores material identity, utility, attributes, virtues, vices, construction prowess, industry impact, journalistic coverage, ecological footprints, societal engagement, and tangible projects. Comparisons are made based on sustainability impact, economic viability, and current trends. The findings reveal that Rammed Earth stands as a sustainability luminary, leaving a minimal environmental footprint. In contrast, Solar Pavement holds intriguing promise, requiring further research, development, and audacious pilot endeavours to fully unleash its potential. This saga offers valuable insights into the strengths and weaknesses of these avant-garde materials. Armed with this knowledge, decision-makers in sustainable construction can lead us towards a harmonious future for our built environment.

THE THERMAL CONDUCTIVITY ENHANCEMENT OF ASPHALT SOLAR COLLECTOR: LITERATURE REVIEW

This comprehensive review article presents an in-depth examination of the augmentation of thermal conductivity in asphalt solar collectors, emphasizing the importance of modified asphalt mixtures and their influence on the efficiency and longevity of solar pavements. The manuscript elaborates on the implications of thermal conductivity for the physical, mechanical, and thermal attributes of asphalt, and investigates various methodologies for modifying asphalt mixtures, such as the integration of thermoplastic elastomers, crumb rubber, polymers, poly-phosphoric acid, and nanomaterials. Moreover, the review accentuates techniques for amplifying thermal conductivity, encompassing the incorporation of metallic particles, carbon nanotubes, graphene, graphite, and phase change materials. Subsequently, the article delineates distinct approaches for assessing thermal conductivity in modified asphalt, comprising steady-state and transient methodologies, and underscores the necessity of selecting a suitable technique based on project specifications and limitations.This review shall add to local knowledge an important engaged in the advancement of effective and sustainable asphalt solar collectors.

A comparison of solar and conventional pavements via life cycle assessment

The sustainable and green development of roads is lately receiving significant attention. As a multi-functional road capable of both accommodating traffic loads and generating clean energy, solar pavements exhibit a strategic opportunity for the future path of development in the road engineering. Although solar pavements have significant environmental benefits during their operation, they can lead to increased carbon emissions during the process of material preparation, construction, maintenance, etc. Therefore, it is essential to implement the framework of Life Cycle Assessment (LCA) to investigate their potential environmental impacts and/or benefits. Hence, this paper systematically analyzes the energy consumption and emissions of solar pavements based on LCA. The results show that the total energy consumption and gas emissions of the solar pavement are far greater than those of the traditional asphalt pavement. Nevertheless, in long-term the power generation function of the solar pavement has significant energy and environmental benefits.

Numerical Investigation of the Mechanical Response of Solar Pavement Based on Cement Concrete Under Vehicle and Temperature Loading

Numerical Investigation of the Mechanical Response of Solar Pavement Based on Cement Concrete Under Vehicle and Temperature Loading

Joint design and load transfer capacity analysis of photovoltaic/thermal integrated pavement unit

The fossil energy on the earth is limited, and with the energy shortage and the environment deterioration, there is an urgent need to develop and use renewable energy. Therefore, solar roads came into being. The current research on the structural performance of solar pavement is relatively lacking, especially the joint design between photovoltaic (PV) pavement unit structures. In order to fill this research gap, in this study, two different PIPVT unit joint designs for photovoltaic/thermal integrated pavement (PIPVT) are proposed, namely, dowel bar joint design and tongue-and-groove joint design. The load transfer capacity of the two joint designs is compared and analysed by ABAQUS simulation. By the result of simulation, the most unfavourable load position was determined, and the load transfer coefficients of the two joint designs were calculated to verify the reasonability of the two joint designs, and to compare and select the scheme. The results showed that the load transfer coefficient of the dowel bar is 75.7%, and its load transfer grade is medium; the load transfer coefficient of the tongue-and-groove joint is 88.9%, and its load transfer grade is excellent. It is recommended to use the tongue-and-groove joint design.

Simulation of structure and power generation for Self-Compacting concrete hollow slab solar pavement with micro photovoltaic array

To explore new solar pavements, a self-compacting concrete hollow slab solar pavement based on a micro photovoltaic array was proposed. The hollow slab solar pavement is composed of three layers: a surface transparent protection slab, a middle micro photovoltaic array, and a bottom concrete base slab. Using ANSYS software and PVsyst software, through the 3D finite element numerical simulation and power generation simulation of the pavement structure, based on orthogonal experimental design and single-factor sensitivity analysis, the structure size of the hollow slab and the layout mode of the micro photovoltaic array were optimized. Then, the optimal hollow slab model was determined. The results show that the optimal size of the hollow slab is 1000 × 1000 × 250 mm; the tilt, azimuth, pitch and edge distance of the solar cells in the best layout mode of the micro photovoltaic array are 18°, 0°, 45 mm and 65 mm, respectively; the power generation capacity in the first year is 140.697 kWh. The life cycle economic analysis indicates that the increased cost can be recovered through the power generation income after 10.2 years, and 1 km of two-way four-lane pavement could reduce by 2.15 × 107 kg of CO2 emissions, with good economic, social, and environmental benefits.

Preparation and performance study of solar pavement panel based on transparent Resin-Concrete

In order to realize the transformation and utilization of renewable energy, a new solar pavement module, which can harvest solar energy using often uncovered pavement/road surfaces, is proposed and investigated in this paper. The module consists of a protective layer made of transparent resin-concrete and a built-in solar panel. The effect of different gradations and resin quantities (five gradation type of the glass aggregate, three kinds of resin content) on the optical properties, volume index, and mechanical properties are studied, and the pavement performance. Then a prototype of the module is built according to the optimized mix ratio. The pavement performance and photoelectric performance of solar pavement module were tested. Finally, the glare performance, sustainability of the transparency was conducted, and the economic-environment benefits were evaluated. The observed results of mix ratio design of optimal show that both the gradation type of the glass aggregate and the resin quantity have a significant impact on the optical properties and the mechanical properties but little effect on the volume index. Both the optical properties and compressive strength of the transparent resin-concrete improve with increasing resin fraction, while its density and void-ratio degrade. Considering material properties and cost, the optimal resin content is 43.7%. It was proved that solar pavement module had excellent high-temperature stability, low-temperature crack resistance, good water stability, good impermeability, and good skid resistance. The daily power generation of the solar pavement panel module is 0.152 kWh/m2, which is about 16.28% of the original solar panel. The surface glare of transparent resin-concrete is 1.3 ∼ 1.5 and 1.7 ∼ 5.9 times than that of concrete and asphalt pavements, respectively, and the light-transmission decreases with increasing surface pollutants. The LCOE of transparent resin-concrete solar pavement is 0.175 $/kWh, and can bring considerable economic, and emission reduction benefits.

A review on solar pavement and photovoltaic/thermal (PV/T) system

In recent years, highway construction field has made huge efforts to develop energy harvesting solutions, such as solar pavement, which mainly on photovoltaic (PV) pavement and thermal energy harvesting pavement. Due to low energy utilisation efficiency and short operating life of PV cells without heat dissipation, the concept of pavement integrated photovoltaic/thermal system (PIPVT) is proposed, which organically combines the above two main solar pavements. Since there is no available research on PIPVT technology for roads, a comprehensive review on building integrated photovoltaic/thermal (BIPVT) system, the PV pavement, and thermal energy harvesting pavement were made to explore the technical feasibility of PIPVT. The initial design of PIPVT has been proposed according to the findings of our previous works, which can improve solar comprehensive utilisation efficiency, as well as the life of PV cells in theory. This review can provide new ideas for future research on energy harvesting pavement.

Development of structure model of hollow slab for solar pavement based on light-guide concrete

To develop a reasonable structure type of solar pavement, a kind of structure model of hollow slab was proposed for solar pavement based on light-guide concrete in this paper. It is composed of two parts: a rectangular hollow slab of light-guide concrete with an arch chamber as well as a solar panel which is installed in the arch chamber. Each light-guide body is compounded of a convex lens, a prism and a light-guide fiber. Through building a three-dimensional finite element model for the pavement structure of hollow slab, the mechanical responses of hollow slab were numerically simulated, thus the geometric sizes of arch chamber were optimized according to the requirements of bearing capacity. By establishing a simulation analysis model of light path for the light-guide body, the total solar energy of single day transmission for the light-guide body were numerically simulated, then the geometric sizes and optical parameters of light-guide body were optimized according to the condensing and light-guide performances. Accordingly, the steel shaping die was designed and manufactured, and the hollow slab model of light-guide concrete was prepared by taking self-compacting concrete as slab matrix. The mechanical properties and the power generation efficiencies were tested for the model. The results show that the developed hollow slab of solar pavement based on light-guide concrete has high strength, and its working voltage and maximum output power increase with the increase of the number of light-guide bodies. Therefore, the model can meet the dual function requirements of safe driving and clean power generation.

Engineering Tests to Evaluate the Feasibility of an Emerging Solar Pavement Technology for Public Roads and Highways

Concrete and asphalt are the primary materials used to construct roadways for motor vehicles, paths for pedestrians and bicyclists, and runways for aircraft. Solar Roadways®, Inc. (SR) proposed a novel solar pavement technology (i.e., solar road panels (SRP)) as an alternative material and energy source. SR performed load, traction, and impact testing to use SRPs in non-critical applications like parking lots. To use SRP in public roads, engineering tests including freeze/thaw, moisture absorption, heavy vehicle, and shear testing were accomplished on “SR3” prototypes. Testing was performed at Marquette University in the Engineering Materials and Structural Testing Laboratory and the SR Pilot Project area. Moisture absorption and freeze/thaw tests showed “SR3” resistant to extreme weather and moisture environments. Heavy vehicle testing revealed no physical damage to the “SR3” after approximately 989,457 equivalent single axle loads were continuously rolled over a prototype pavement. Shear testing was conducted to investigate “SR3” laminate structure properties. In all cases, electrical failure was defined when “SR3” photovoltaic voltage dropped to zero volts. The maximum shear stress and applied torque for “SR3”’ (S/N’s Paver 1, 002B, 007C, and 004B) were 1756 kPa, 1835 kPa, 1643 kPa, 2023 kPa; and 121.2 kN·m, 131.3 kN·m, 117.6 kN·m, 144.8 kN·m, respectively. In addition, the “SR3” “heartbeat” light emitting diode (LED) remained operational (i.e., indicates computer bus traffic) in all phases of shear testing. Overall, the results show “SR3” prototypes to be robust, resilient, and functional when subjected to “real-world” test conditions.

A review on the latest trend of Solar Pavements in Urban Environment

Renewable Energy has evolved into an integral part of the future Energy Landscape. Their unique feature of being perpetual and consumed close to the loads and thus within the urban environment, leads to new ways of their integration. Solar Collector Pavements are the latest trend of integrating Renewables within the urban mesh by creating operational and efficient sources of energy for different applications. Solar collector pavements harvest energy from sun to provide ancillary services within the smart city concept. They alleviate the city environment from the thermal capacity by storing energy (thermal or electrical) and when necessary use it to cover buildings’ thermal loads, power lights, street signs or even cover electric bicycles needs.This paper reviews the latest progress on solar collector pavement technology and categorizes the different technologies of this trend by their potential applications in the urban environment. It also reviews and sum up the features of each application and the barriers that may hinder the solar pavement approach at the time. It also presents the related pilots around the world and discusses what steps need to be taken before the trend gets mainstream.

Current Situation and Development Trend of Solar Pavement Technology

This study focused on the current situation and application examples of the solar pavement technology across the globe. The development trend and application potential of this technology were analyzed systematically in terms of surface structure, load-bearing capacity, road performance, security and the integrated smart control function. The technological difficulties and research directions were then proposed. After that, the recommendations for further progress in the technology are provided, giving suggestions on the development of the solar pavement technology in China.

Solar pavement: A new emerging technology

The present work is conducted to evaluate the feasibility of using solar pavements as a sustainable energy producer to supply electrical energy. For this purpose, we prepared two prototypes entitled as “solar panel” (solar cell embedded in rubber and Plexiglas) and “solar pavement” (solar cell embedded between two porous rubber layers) which both are capable of harvesting and converting the solar energy into photovoltaic cells. In this work, components of the new solar pavements were introduced. These two designed pavements were evaluated in terms of supply energy, surface safety movement, and structural performance. The British Pendulum Tester (BPT) and Universal Test Machine (UTM) were used for measuring surface frictional properties and determining the dynamic property of solar pavement, respectively. Moreover, the drainage test was investigated for both prototypes. To survey the feasibility of solar pavement to achieve the electrical energy through solar cells, I-V (current-voltage) measurements were carried out to record the current and voltages of the solar cells embedded in the pavement under different conditions and determine their power conversion efficiency (PCE). The BPT values for solar panel and solar pavement under the wet condition were measured as 42 and 47.8, respectively. Also, the drainage test showed that the average volumetric flow rates of solar panel and solar pavement are 0.018 and 0.042L/s, respectively. Moreover, the value of drainage test was 0.0224L/s in asphalt pavement. The solar pavement in comparison to solar panel showed a higher PCE value of 5.336%. Besides, based on the UTM results, the flow number (FN) is 1002 with 49mm deformation for solar panel and 1260 with 65mm deformation for solar pavement. The UTM results also showed that solar pavement improves rutting performance in comparison with a solar panel. Thus, adding a new layer of the solar cell and rubber solar pavement could enhance strength parameters and electricity generation for transportation application.

The Potential of Heat Collection from Solar Radiation in Asphalt Solar Collectors in Malaysia

The implementation of asphalt solar collectors as a means of an energy source is being widely studied in recent years. Asphalt pavements are exposed to daily solar radiation, and are capable of reaching up to 70°C in temperature. The potential of harvesting energy from solar pavements as an alternative energy source in replace of non-renewable energy sources prone to depletion such as fuel is promising. In Malaysia, the sun intensity is quite high and for this reason, absorbing the heat from sun radiation, and then utilizing it in many other applications such as generating electricity could definitely be impressive. Previous researches on the different methods of studying the effect of heat absorption caused by solar radiation prove to be quite old and inaffective. More recent findings, on the otherhand, prove to be more informative. This paper focuses on determining the potential of heat collection from solar radiation in asphalt solar collectors using steel piping. The asphalt solar collector model constructed for this research was prepared in the civil engineering laboratory. The hot mixed asphalt (HMA) contains 10% bitumen mixed with 90% aggregates of the total size of asphalt. Three stainless steel pipes were embedded into the interior region of the model according to the design criteria, and then put to test. Results show that harvesting energy from asphalt solar collectors proves highly potential in Malaysia due its the hot climate.

Asphalt Concrete Road Surface Summer Temperature Prediction Based on Radiant Balance Theory

By using energy balance method and considering the balance among solar short wave radiation, atmospheric and pavement surface long wave radiations, latent heat fluxes and sensible heat fluxes, a prediction model for AC road surface temperature is established. The pavement temperature and meteorological observation data of Ningbo city (from 2009 July 15 to 2009 August 13) have been used to validation of the model. The results show that a high accuracy was existed between the measured and calculated temperature in the clear days. when S (daily sunshine-ratio)>60%, the maximum absolute error of calculated daily maximum pavement temperature is less than 3 °C, and the multi-day mean absolute error is 1.5 °C. But in cloudy or rainy days, the model’s accuracy will be lower than the clear days.