Capturing Solar Energy from Asphalt Pavements

The concept of extracting heat energy from asphalt pavements has been investigated in this study. The scope of work consisted of finite element modeling and testing with small and large scale asphalt pavement samples. Water flowing through copper tubes inserted within asphalt pavements samples were used as heat exchangers in the experiments. The rise in temperature of water as a result of flow through the asphalt pavement was used as the indicator of efficiency of heat capture. The results of small scale testing show that the use of aggregates with high conductivity can significantly enhance the efficiency of heat capture. The efficiency can also be improved by using a reflectivity reducing and absorptivity increasing top layer over the pavement. Tests carried out with large scale slabs show that a larger surface area results in a higher amount of heat capture, and that the depth of heat exchanger is critical. An effective heat exchanger design will be the key in extracting maximum heat from the pavement.