As much as we love the good, old-fashioned internal combustion engine, it's rather hard to avoid discussions around electrification and hybrids, especially when shopping for a new car. The hybrid moniker is bandied about left, right, and centre these days as virtually all manufacturers try and reduce their carbon footprint by electrifying their model lineup in some shape, way, or form.
Related: What is the difference between electric and hybrid cars?
All of the various ways that this can be executed can become somewhat confusing and we get that. There are Plug-In Hybrids, Series-Parallel Hybrids, Range Extenders and yes, Mild Hybrids. Some of these make logical sense but there still seems to be some grey area around mild hybrids.
What is a hybrid?
In short, any vehicle that receives some assistance from an electrical system to help reduce fuel consumption or improve performance is considered a hybrid. It bridges the gap between full-electric vehicles and traditional vehicles that use fossil fuels for propulsion. These fossil fuel vehicles are also commonly referred to as ICE vehicles (Internal Combustion Engine).
Hybrid vehicles still use an ICE power plant but this unit is supplemented by a battery pack and often an electric motor to help improve performance or reduce fuel consumption.
What is a mild hybrid?
Mild hybrids are, as the name suggests, a stripped-down version of regular hybrids in many instances. This system will use a considerably lower voltage to supplement the ICE unit and in most instances improve fuel consumption only. Some manufacturers do use the lower-power 48-volt system to help boost the engine but this isn't used for outright speed and power but more to fill in the gaps where the ICE unit is less effective (ie: out of boost or between gear changes).
Most mild hybrid systems use the electric system to restart the engine when it has shut down as part of the stop/start system. The stop/start system helps reduce the waste of petrol or diesel by shutting down the engine when the vehicle stops at an intersection or in heavy, gridlocked traffic. The mild-hybrid system is then used to restart the engine as it's more efficient than activating the regular starter. This also helps with the concerns over premature wear and tear on the starter motor in stop/start-equipped vehicles.
The mild-hybrid system usually consists of an integrated starter/generator and will often employ regenerative braking to help charge the small battery unit that is called upon when the electric motor is used to assist the ICE unit or when restarting the ICE unit.
Mild hybrids do not have a full-electric mode and they do not require any additional input from the driver in the way of charging or setting up the system. Mild hybrids are not as fuel-efficient as full hybrids or fully electric vehicles.
