Transportation and Energy Harvesting
Energy Harvesting from Infrastructure
Transportation system is one of the largest and most important infrastructures in modern society. According to Federal Highway Administration (FHWA), a total lane mile of the public roads in the US is 8.6 Million miles in 2012. In the US, 28% of total produced energy was consumed by transportation sector in 2012. While the moving of vehicle is the major energy consumption of the transportation sector, the transportation facilities uses 25×10^12 BTU of electrical energy for the roadway lighting, signal, and various sensing and monitoring systems. Additionally about 51×10^12 BTU, which is about twice that actually consumed, is lost from transmission during power delivery. This is caused by the widespread nature of roads.
Energy harvesting reclaims otherwise dissipated or wasted energy, and is highly sustainable power generation approach. While energy harvesting technology has successfully been explored in numerous electronics and mechanical systems applications, its application to roadway pavements is currently at its infancy. Since asphalt pavement is a huge storage of solar energy, the pavement energy harvesting technology promises a significant breakthrough in attaining renewable energy at a massive scale. The specific attributes of harnessing energy from pavements are: 1) the size of roadways is massive, and hence, relatively large amount of energy can be collected, 2) there exist various types of available energy sources, e.g., geothermal, solar, mechanical, etc., and 3) a long-distance power transmission is not necessary because the collected electrical energy can be consumed in place by traffic facilities. In situ generation of electrical power can decidedly offset the aforementioned transmission loss of electrical energy. In addition, it can eliminate the installation and maintenance cost of power delivery infrastructures. I am conducting collaborative research with experts in electrical engineering for developing materials and systems that can generate and store electrical power from civil structures.
Energy harvesting reclaims otherwise dissipated or wasted energy, and is highly sustainable power generation approach. While energy harvesting technology has successfully been explored in numerous electronics and mechanical systems applications, its application to roadway pavements is currently at its infancy. Since asphalt pavement is a huge storage of solar energy, the pavement energy harvesting technology promises a significant breakthrough in attaining renewable energy at a massive scale. The specific attributes of harnessing energy from pavements are: 1) the size of roadways is massive, and hence, relatively large amount of energy can be collected, 2) there exist various types of available energy sources, e.g., geothermal, solar, mechanical, etc., and 3) a long-distance power transmission is not necessary because the collected electrical energy can be consumed in place by traffic facilities. In situ generation of electrical power can decidedly offset the aforementioned transmission loss of electrical energy. In addition, it can eliminate the installation and maintenance cost of power delivery infrastructures. I am conducting collaborative research with experts in electrical engineering for developing materials and systems that can generate and store electrical power from civil structures.
Charging with Harvested Energy While Driving
While the electric vehicle technology has higher energy efficiency and reduced pollution than fossil fuel vehicles, the widespread of electric vehicles have been hindered by some barriers such as long charging time at power station and short travel time. The dynamic (charging while driving) inductive charging system is the solution to resolve these issues. In addition, energy harvesting is highly sustainable method of power generation, and can be cost effective at interstate highways away from the existing power grid. The combination of the highly sustainable power generation and inductive charging technologies will lead a breakthrough for sustainable transportation system.
Thermoelectric Energy Harvesting
With the goal of optimizing the thermoelectric energy harvesting system for the pavement application, various factors affecting the efficiency of the energy harvesting system were investigated. A series of experiments are conducted using a prototype thermoelectric energy harvesting system composed of the heat exchanger and thermoelectric generator (TEG). The results obtained from the theoretical and experimental investigations indicate that the controlling of the heat flow within the system has significant effect on the useful power output. The methods of electrical and thermal impedance matching in selecting an efficient TEG are proposed and experimentally verified. The effects of the thermal impedance and insulation of the heat exchanger are also evaluated. Among the various combinations of the TEGs and the heat exchanger geometries, the best combination of the device configuration and setup yielded over 40 mW at the load. Design optimization process has produced a system that achieves power output greater than 25 times that of the default design in this study. Given the stated temperature differential, and the device capacities, the power results obtained is about 800 times higher than the power output of the one of the most recently reported study on the pavement energy harvesting using TEG.