Small petrol engine will be backed up by an electric motor

Saab is planning to introduce a hybrid assist system on its new 9-5, using a small petrol engine backed up by an electric motor in a bid to cut fuel consumption and emissions.

The Swedish company is developing a 9-5 with a turbocharged 1.4-litre petrol engine. This unit will be assisted during periods of acceleration by an electric motor sandwiched between the engine and transmission.

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The big advantage of an electric motor is that it offers high levels of torque from idle. In the Saab the electric motor will come on stream when the driver is pulling away or accelerating.

However, when the car is cruising the 120bhp 1.4-litre engine has more than adequate power on its own. The result should be diesel-matching economy with petrol engine refinement, lower pollutant levels and impressive acceleration.

The system works on a similar principle to the drivetrain in the BMW Vision Efficient Dynamics, which has a 1.5-litre diesel powerplant boosted by a pair of motors.

Because the hybrid assist is only used in short bursts, the car’s battery pack can be small and relatively cheap — a key factor, given that Saab wants the 9-5 to undercut its main German rivals.

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9 September 2009

So its roughly the same system used by Honda and Toyota then. Sounds more like the Honda version though, so it shouldnt add too much to the price. Its going to be be very hard in the years to come getting used to the idea of cars this size running with tiny engines, but i guess we have to get used to it.

I look forward to hearing more. I hope for Saabs sake its a decent effort.

9 September 2009

thats the way, small capacity, lightweight and cheap battery packs. good strong electric motors and a decent petrol punchy engine to keep things in order. i approve.

this is where the technology needs to be for 10 years to develop and for the prices to come down, not in mass market medium to small family cars.

i'm for the KERS type effect seen in F1 this is how i think the development should go, and extra 80bhp on tap for short intervals is all that any driver needs on public roads. even for the boy racer in us all when we give it full beans on empty country roads we only need that power for say 5 minutes at a time, only tiny battery packs are needed for this short duration power shots, the rest of the time we can make do with very small output petrol engines which are very efficent. which can recharge the capictors/battery pack with some assitance for kinetic energy recovery.

i am disappointed F1 is standardising KERS and not allowing a technology war, this is where the money needs to be researched. hopefully the £40 million budget cap will come in and them the regualtions will change.

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