UNMASKING THE MILD HYBRIDS
Land Rover Philippines recently announced the pricing for the new Range Rover Evoque and it's available with MHEV (mild-hybrid electric vehicle) power. I'm a big fan of mild hybrid vehicles and believe they save fuel while increasing performance. That's having your cake and eating it too.
What is a hybrid vehicle? Hybrid vehicles are vehicles with an internal combustion engine (gas or diesel) and at least one electric motor. They can run on the engine alone, by the electric motor or combined. Having an electric motor sharing the burden improves fuel economy.
Mild hybrids, on the other hand, can't often run on electric power alone. And, if they do, range is very limited to a few miles. The Ferrari LaFerrari and the McLaren P1 supercars are case-in-point.
Mild hybrids are always Parallel Hybrids in the sense that both power sources con
nect to a common transmission. Since the electric motor simply aids the internal combustion engine ( ICE) in mild hybrids they cannot be of Series design. Series Hybrids rely on the electric motor for propulsion and the job of the engine is simply recharge the battery.
Mild hybrids can't save fuel as much as full hybrids but they are easier to adapt to traditional powertrain vehicles which may not have been initially designed to have a hybrid system. When Mercedes-Benz introduced the mild hybrid S400 in 2010, it sandwiched an electric motor between the engine and the 7speed transmission. The standard S-Class drivetrain layout remained and the same 7GTronic transmission transferred power to the wheels. Mild hybrid cars also simply look like their non-hybrid counterparts.
Mild hybrid systems can be found on the aforementioned Range Rover, Jeep Wrangler, 1500 RAM pickup, many Benzes, some Audis, Volvos, Kias and Hyudais, and optional on many U.S.-market GMvehicles.
Mild hybrids allow stopstart capability, can shut- off the engine while coasting and often employ regenerative braking to aid in charging the battery. All of these burns less fuel and cuts emissions by reducing engine load. The electric motor in mild hybrids may not always be intended for fuel savings but to increase overall power and lowend torque. Electric motors produce maximum torque from zero rpm while engines do not. Adding an electric motor to assist a high- revving supercar ( LaFerrari, P1 and 918) engine or small- displacement Jeep Wrangler engine solves the problem of a peaky engine with less than ideal low- end grunt. The result can be slingshot acceleration or rockcrawling ability at idle speeds.
The practicality, cost, weight, compactness and performance of the mild hybrid method will eventually allow manufacturers to "hybridize" all their models. And, unlike the flu, a case of the mild hybrid is a good thing.