The Mercedes S-class is a remarkable and class-leading car in a lot of ways, but with the arrival of the S300 Hybrid this luxury saloon is now spectacularly efficient too.
Combining a 2.1-litre diesel with a small, 20hp-equivalent electric motor has created an S-class with a 61.4mpg official figure to go with 120g/km of CO2.
The best the Mercedes’ main rivals can manage in long-wheelbase form is 146g/km for the Audi A8 hybrid, 148g/km for BMW’s 730d and 167g/km for the Jaguar XJ saloon
The electric motor kicks in at low speed to run the car independently while the diesel engine shuts down, and will be useful in heavy London traffic, for example, although it is a challenge to feather the throttle to the extent where the diesel engine doesn’t kick-in.
This is helped by the dashboard indicator of how far you are away from maximum electric power, while the right foot can be adjusted accordingly to keep it on electric only. Unlike a plug-in hybrid, the battery is recharged exclusively from energy recouped when the car is braking.
However, a full plug-in hybrid S-class is due by the end of the year, offering a 69g/km figure that will mean London congestion charge exemption and a 5% BIK band. As it is, this S300 Hybrid is only in the 17% band, five better than any rival. The next-best A8 petrol hybrid costs a 40% tax payer an additional £82 each month in BIK, if the owner is paying such a thing.
Overall, the S300 isn’t the most rapid form of luxury travel, and the 231hp is down on rivals’ power, but this sort of car is more likely to focus on being comfortable and classy, and that is where it excels – even more so now it is capable of silent running at low speed with the engine off thanks to the hybrid system.
The huge efficiency lead, with its fuel and tax advantages, and a strong comparative RV, means a clear cost per mile victory for the Merc. At 130.4p per mile, it is at least 4.8p ahead of any rival, despite starting out at around £5k more expensive than the Audi, BMW or Jag.
