Lotus has unveiled a new hybrid powertrain system called EVE, which it says could allow conventional front-drive cars to be converted to Toyota Prius-style hybrid motivation inexpensively.
Described as a 'technological demonstrator', the drivetrain is based around a conventional 1.8-litre petrol engine and CVT transmission. Lotus engineers have added a stop-start system (which switches the engine off when the car is stationary, before automatically re-starting as the driver wants to drive off) and sandwiched an electric motor between the engine and the CVT box.
This electric motor can provide pure electric running or can be used in conjunction with the petrol engine for better performance. The car can also pull away from rest in pure electric mode to reduce road-side pollution, with the engine cutting in once the car is moving. The drivetrain package also incorporates the complex electrical controller that balances engine and electric motor function when the car is running.
The whole powerpack slots straight into the front of the Proton Gen 2 demonstrator vehicle, and the battery needed to power it takes up around 25 per cent of the boot space.
Lotus engineers say that just adding the stop-start system will reduce fuel consumption by between 5-7 per cent over the factory-fit petrol engine. With a full hybrid powerpack, the savings could be around 28 per cent. The hybrid drive also reduces the 0-60mph time of the stock Gen 2 from 12.5sec to just 9sec, so it's possible that a car maker could take advantage of the full hybrid drive to further downsize the engine, with no loss of performance.
There are no plans for full production as yet, because Lotus says it just wants to prove to potential customers that hybridising a conventional family car is not only possible, but might add no more than 12 per cent to the showroom price.