The Sportage MHEV (Mild Hybrid Electric Vehicle) will greatly assist in reaching the average vehicle emission target of 95 g/km CO2 in 2020.
Ahead of the open weekend at Gay Lawton Motors, Edenderry Topic spoke to Gay to find out more about MHEV, what exactly it is, the benefits and how it works.
What is a MHEV?
A Kia Mild Hybrid Electric Vehicle consists of an Internal Combustion Engine (ICE) and a small electric motor which assists the ICE when it is under heavy load (E.g. accelerating or climbing hills).
What are the benefits of MHEVs ?
A MHEV has better fuel economy and is more eco-friendly than a conventional engine.
Kia MHEVs save up to 4% fuel consumption and emit 15% less CO2 compared to traditional combustion engines.
The EU target of average vehicle CO2 emissions in 2020 is 95 g/km. A fine of €95 will be imposed for each g/km that is over the limit (average vehicle sold emissions).
MHEVs will greatly assist in reaching this target.
What components are fitted to an MHEV
A small electric motor called the Mild Hybrid Starter & Generator (MHSG).
The MHSG is positioned on the side of the engine and provides power through the Ribbed Drive Belt to the internal combustion engine via the crankshaft pulley.
A 48v battery: Located in the rear of the vehicle (inside the boot area) which provides power to the MHSG.
The 48V battery is Lithium-Ion. It has 12 cells and a rating of 0.44kWh
A 12v battery: Located in the engine bay, it powers the normal electrical systems (lights, ICE engine, wipers etc.).
A 12v starter motor: This is only used for cold starting (further explanation below).
A 12v alternator is NOT fitted to this system as the 12V battery is charged by “stepping down” some of the voltage from the 48V system.
How does it work ?
Cold Starting: The MHEV system makes use of a normal 12 V starter to crank the engine under cold engine conditions.
Low speed /load driving: During low speed driving, the vehicle only uses engine generated power to drive the vehicle.
When moving from a stopped position, accelerating or driving the vehicle uphill: The MHSG provides power assist to the ICE through the ribbed drive belt.
This power assist will provide additional output in the low and high rpm range of the engine, where the torque curve is not ideal.
By doing so the ICE does not need to generate as much torque in these inefficient operating ranges, which reduces fuel consumption/emissions
Stop-Start: Whenever the vehicle is coasting, braking, or stopped, the combustion engine will shut off to save fuel and reduce emissions.
To restart quickly (and quietly) the vehicle uses the MHSG as a starter.
Unlike standard ISG (Idle Stop and Go, or Stop/Start) systems the MHEV can turn the engine off at speeds lower than 30 km/h to save more fuel.
The MHSG can then seamlessly re-ignite the engine – in any situation – if the driver presses the throttle pedal.
Mild hybrids do not operate in electric-only mode.
Charging the 48V battery: During deceleration/overrun the Sportage MHEV uses some regenerative braking to recover energy to the 48V battery.
Also, when the available engine output exceeds the required load, the MHSG charges the 48 V battery via the combustion engine.
The the new Kia Sportage Diesel Hyrbrid MHEV is available to see at Gay Lawton Motors, Edenderry. Why not attend their Open Day this Saturday, or Sunday, 9th / 10th November to see for yourself the benefits of this spectacular SUV.