What Is A Supercapacitor?
A supercapacitor is a high power density energy storage device that can be used in smaller UPS systems (up to 30 kVA) instead of the usual batteries to protect against momentary mains power supply failures.
Supercapacitors differ from an ordinary electrolytic capacitor in two main ways: their plates are much bigger, while the distance between them is smaller because the separator works differently to a conventional dielectric. This means supercapacitors can store 10-10,000 times more energy per unit volume than a standard capacitor.
Compared to traditional sealed lead-acid UPS batteries, which have a higher energy density, a supercapacitor’s power density can be up to 100 times greater, so it can release energy far quicker.
This means supercapacitors are perfect for critical power applications where loads might be sensitive to small breaks in mains electricity (i.e. from 1 second to 1 minute). For example, they can provide sufficient backup for a standby generator to start-up.
Supercapacitors have a typical service life of up to 10 years and can operate at a wide temperature range of -30°C to +45°C.
They currently remain an emerging technology so are more expensive than a standard UPS battery set. However, their longer lifespans and high number of cycles offer long-term savings if you take into account reduced battery monitoring, maintenance, replacement and removal costs.