Complimentary roles
Supercapacitors and batteries complement each other in a range of applications, with supercapacitors smoothing out any short-term disruptions in power quality while batteries store current for longer term load levelling applications.
An important application for supercapacitors is ‘dynamic sag correction’ in electric power grids. This requires that energy be delivered to or extracted from the grid at specific locations to prevent voltage oscillations that can occur when loads are abruptly removed or added.
In addition grid storage using supercapacitors and batteries allows stored electricity from non-peak demand periods to be used during peak load times (load levelling). Supercapacitors are also useful for solving power reliability issues since they can be sized to deliver sufficient energy over the period of time needed for example to start a back-up diesel generator set.
Renewable energy production through wind turbines and solar panels requires similar storage capability and load levelling because of the unpredictable nature of wind and sunshine. Stored energy (in the form of batteries and supercapacitors) is required to even out the peaks and troughs in production so that a predictable source of power is always available.