Energy in the Future series: What is the potential of Supercapacitors for energy storage and transfer?
Like the automotive industry, the rail industry can use supercapacitors onboard rolling stock for regenerative braking and start-stop systems. The supercapacitor can use surplus energy from braking to provide energy for acceleration, while a battery can provide range and recharge the supercapacitor between surges. Excess energy could be used to power train stations via reverse-supply power substations. Consequently, this could reduce operational costs, maintenance costs, energy dependence, improve voltage stability and increase energy efficiency. In addition, supercapacitors with load levelling control can be used in conjunction with fuel cells, which could result in hybrid rolling stock with a fast and dynamic response. Results from simulations carried out by the Institute of Transportation Studies have suggested that automotive vehicles could achieve greater fuel efficiency and reduce the electrical and mechanical stress on fuel cells through the use of supercapacitors.