The Korean manufacturer is considering shelving its planned hybrid diesel engine because of increasingly tight emissions legislation
22 August 2016

Kia is considering shelving its electrically boosted hybrid diesel engine project as the Dieselgate fallout continues.

Although the project is still officially under way, Kia performance development boss Albert Biermann has admitted it is becoming hard to justify the development of more expensive diesel engines in the face of increasingly tough emissions standards.

“The research project is still going on,” Biermann told Autocar, “but the cost of electric motors and batteries in a hybrid is already significant. The question is whether it is really necessary to throw in a more expensive diesel engine.”

The research is unlikely to be wasted. Biermann suggested the hybrid system might well be re-engineered to work with a petrol engine. He said: “We also have a very efficient Atkinson-cycle gasoline engine, so I think that is the good choice here.”

The project was introduced with the Optima T-Hybrid, which was first shown at the 2014 Paris motor show. This featured the familiar Hyundai-Kia 1.7 CRDi diesel engine, which was boosted by a 48V electric supercharger - similar in principle to the one Audi has just introduced on the considerably more expensive V8-powered SQ7 TDIThis set-up worked in conjunction with a 48V starter/generator that turned it into a mild hybrid.

Kia estimated that a production version would be able to cut the emissions and fuel consumption of any car it was fitted to by 15-20%. 

Our Verdict

Kia Optima

The Kia Optima has looks, practicality and value on its side. But in a class of talented models, it is an also-ran.

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22 August 2016
Common sense prevails. At the lower end of the market it made me wonder how such intelligent people would think it such a good idea to put a bigger, more expensive, noisey, heavy, harsher engine next to a silent Electric motor when it's only mpg advantage over petrol is smaller when compared to normal petrol versus diesel running costs due to it being a hybrid.

typos1 - Just can’t respect opinion

22 August 2016
The opposite is true - for a hybrid you want to improve on C02 and MPG figs, so its best to start with an engine that already achieves this (ie diesel). Whats the point in starting with an engine that has poor C02 and mpg figs (petrol), throwing expensive batteries and electric motors at it only to produce a car with worse C02 and mpg figs than a diesel car ? Stupid.

XXXX just went POP.

22 August 2016
They already have a great petrol engine hybrid system fully developed they are rolling out in the new Niro. There its been usefully put to use to create a direct Nissan Qashqai crossover competitor but with a significantly lower company car tax liability attached to it, with no downsides.

22 August 2016
Diesel hybrid is a terrible idea on cars, for reasons stated above. I can see the technology working for long distance road haulage though, with a diesel motor acting largely as a generator for an electrified drivetrain.

22 August 2016
Ditching the diesel in a family size hybrid car that is likely to spend much of its time in the urban environment only makes sense given the diesel's inevitably higher NOX emissions but Kia could use similar technology in larger cars or trucks and tractors just as the article says Audi did in the Q7. Otherwise they have just introduced a petrol hybrid that at last rivals Toyota's Prius.

22 August 2016
It's all down to cost. If the exhaust after treatment for diesels wasn't so expensive then diesel hybrids would be more common as they would achieve higher mpg than the equivalent petrol.

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