Analysis of the properties of supercapacitors and possible applications for the technology

Supercapacitors have a lot of excellent qualities that would make them a great substitute for batteries when it comes to electrical energy storage systems. Supercapacitors can discharge and charge very rapidly, they have a lifespan in the realm of millions of cycles, and they are much more efficient than batteries. Unfortunately, they cannot hold nearly as much charge as batteries. This paper seeks to further investigate the properties of supercapacitor technology and the best way to exploit these properties with the purpose of integrating them into renewable energy systems. There is currently a lot of research occurring around the world with supercapacitors. This research mostly revolves around improving advanced carbon materials that will allow supercapacitors to have an even higher capacitance so that may begin to truly compete with batteries. Other research is looking to incorporate supercapacitors into renewable systems. This ranges from wind generation systems to solar energy systems to even hybrid battery/supercapacitor storage systems. Undertaking my own experiments, I sought to better understand the properties of supercapacitors by comparing them to standard batteries and by constructing a hybrid energy system that utilizes supercapacitors in tandem with batteries. Over the course of this research, it was determined that, while supercapacitors certainly have very unique and advantageous properties, with their current limits they would best be used in tandem with a battery. However, a hybrid system is possible and supercapacitors can charge a battery, which greatly increases the voltage range that a battery can be charged with. The system constructed contained six 10 F supercapacitors wired in series to a 12 V 20 A battery. The supercapacitor bank was able to charge the battery up to 0.009% of its full charge with one cycle. While this seems to be an insignificant percentage, it demonstrates that a hybrid system would be effective, and scaling up the supercapacitor bank would yield better results. In the future, it would be worthwhile to create a more sophisticated circuit to test this system outside with a real wind turbine. Through future testing, it will be determined how much more efficient it is to capture wind energy with a hybrid system compared to a wind turbine with only batteries for storage

Numerical and Experimental Investigation of Nanostructure-Based Asymmetric Light Transmission Interfaces for Solar Concentrator Applications

Research in asymmetric light transmission interfaces has been recently gaining traction. While traditionally considered for optical circuitry applications, there is a new interest to use these interfaces in luminescent solar concentrators. Previous studies have shown that applying them to the top surface of a concentrator could mitigate surface losses. This paper presents experimental results for proof-of-concept asymmetric light transmission interfaces that may have potential applications in luminescent solar concentrators. The interfaces and the underneath substrate were created in a single step from polydimethylsiloxane using silicon molds fabricated on <100> wafers via anisotropic wet etching. The resulting structures were pyramidal in shape. Large surface areas of nanostructures repeating at 800 nm, 900 nm, and 1000 nm were tested for backward and forward transmission using a spectrometer. Results showed a 21%, 10%, and 0% average transmissivity difference between the forward and backward directions for each periodicity, respectively. The trends seen experimentally were confirmed numerically via COMSOL simulations