Basics

They are more commonly reffered to as "Start-Stop" or "Stop-Start" systems, however Idle-Stop Systems is used in papers etc
Systems for Internal Combustion Engines , typically for Vehicles, where when idle for a certain amount of time (long enough that it isn't a small pause), the engine will turn off automatically
Then when the "gas pedal" is pressed again, or new power is needed for ongoing electronic/mechanical devices once the "reserve" has been used up, it will automatically turn back on
The Starter Motor is typically upgraded to make this faster as well
In situations such as start-stop traffic this can significantly reduce fuel use, and decrease Emissions

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