Supercapacitor technologies for renewable energy application

Abstract

Supercapacitors are increasingly gaining popularity since the advent of “world campaign” for clean energy generation. They are characteristically high power-dense energy storage devices with very low ESR. They are known to have more cycle life and less prone to explosion than the conventional lithium-ion batteries. With Research activities on the rise, supercapacitors could be potential alternatives for the less durable battery energy storage systems.

This paper explores the behaviour of different supercapacitor technologies as energy storage devices. Three different technologies are analysed, they include; The Electrochemical double-layer capacitor, the hybrid supercapacitor and the battery-type supercapacitor. More emphasis was laid on the battery type supercapacitor as the latest supercapacitor technology with a capacitance of 40,000F. Empirical tests were conducted on the devices with the charge and discharge characteristic curves obtained to further analyse their behaviours. To investigate the supercapacitor’s storage capability, a boost converter was designed. The converter enables the 2.7V supercapacitor power a 12V LED. A 150W push-pull converter was also designed to enable a bank of supercapacitors to power a 120V LED floodlight. This was done to demonstrate the commercial applicability of the battery type supercapacitor for street lighting system. Detailed design procedures of the two converters are described, including the Printed circuit board and the push-pull transformer.