Applications

Transportations

Supercapacitors are wide use in the diesel hybrid electric bus, stop-start systems, Automatic Guided Vehicle (AGV), and more.

Automotive Start-Stop

In a stop-start system, the engine is turned off by the engine management system every time the car stops in traffic. When the driver goes to move off – for example, by depressing the clutch in a manual, or releasing the brake and depressing the accelerator in an automatic – then the engine management system starts the engine.

This means the car never idles, saving fuel and reducing pollution. Depending on the traffic conditions, this could save anywhere from 2% to 10% in fuel and emissions reduction.

Hybrid Electric Vehicles

A common implementation of supercapacitors in wide use is the diesel hybrid electric bus. Typically, this is a series hybrid system that uses only supercapacitors for energy storage, but parallel hybrid systems are also in use. These buses are able to downsize the diesel engine by 50%. In the series hybrid, the supercapacitors are used for high power acceleration until the bus reaches cruising speed, and can then be switched to diesel. The supercapacitors are also used to recapture energy during braking, which is highly efficient due to the high-power capability. These buses achieve greater than 25% fuel savings and 10+ year life for the supercapacitors.

AGV (Automatic Guided Vehicle)

An application for supercapacitors growing in popularity is the AGV application. The AGVs have typically used batteries, but suffer from reliability issues, short life, poor power performance, and long recharge times. Compared to the batteries, supercapacitor AGV solutions are lighter, have a much longer life, are more reliable, have high power capability (for lifting operations), and can be rapidly recharged.