In order to comply with new regulations, carmakers are revving up their eco credentials. Shane O'Donoghuereports on new, greener models
A BARRAGE OF new brand names has hit the car market in recent years, each designed to convey a car's green credentials. Volkswagen was one of the first, launching its BlueMotion brand across Europe, swiftly followed by Ford's ECOnetic models. Skoda markets the GreenLine; Seat's take is called Ecomotive; Mitsubishi is planning Clear Tec models, while BMW/Mini's EfficientDynamics already features on over one million cars globally.
There are many more, and though some of these have yet to hit Irish shores, they are well-suited to our new vehicle taxation system and will no doubt feature strongly in 2009.
All of these new models are designed with one common aim in mind: to reduce fuel consumption and hence lower the rated CO2 emissions figure.
Despite protestations from European carmakers, the EU is pushing ahead with plans to introduce new legislation from 2012 that limits average CO2 emissions to 120 grams per kilometre.
Severe financial penalties will be applied to car manufacturers exceeding the limit, so it's not surprising that huge engineering effort is being put into reducing fuel consumption.
In the long term, it's likely that electric and possibly even hydrogen cars will play a larger part in society, but even hybrids are in their infancy, and with the EU legislation deadline looming, carmakers have no choice but to increase the efficiency of current models using proven technology, especially when the plans for a 95g per kilometre limit by 2020 are taken into consideration.
VW's BlueMotion models are a case in point: utilising already efficient turbodiesel engines, the gearbox ratios are tweaked to ensure the engine speed is kept down during the all-important European combined test cycle, while the engine management software is rewritten to provide more torque lower down the rev range.
To maximise these gains, VW also lowers the BlueMotion cars and fits an aerodynamic body kit to reduce drag at speed. Finally, low-rolling resistance tyres are fitted as standard, further improving fuel economy. Unsurprisingly, the VW Group's other brands - such as Skoda and Seat - follow the same strategy, though notably, the BlueMotion, GreenLine and Ecomotive cars are standalone models in their respective ranges, rather than an option across the board.
Ford takes a similar approach with its ECOnetic Fiesta, Focus and Mondeo, with tweaked aerodynamics and low-rolling resistance tyres - though the gearbox is unchanged from the standard car other than the inclusion of low viscosity transmission oil. Volvo's forthcoming DRIVe models are virtually the same, with the addition of smarter control of ancillaries - such as the engine coolant pump - so that they only sap energy from the engine when required.
BMW admits its EfficientDynamics suite of fuel-saving measures came about at just the right time. Unlike virtually all other carmakers, BMW's new technology is standard across a wide range of vehicles, though the number of features varies from model to model. The simplest aspect is a gearshift indicator in the dashboard - now also featured on several other manufacturers' cars - that advises the driver of the ideal gear ratio for best fuel economy.
On top of that, a stop-start function cuts the engine when at a standstill, which has a huge effect on the rated CO2 figure (as the official test cycle includes 12 instances where the vehicle is at a standstill). Less obvious to the driver are the active aerodynamic flaps in the radiator grille and a form of brake energy regeneration.
Kia, Mitsubishi and Mazda have all revealed details of their stop-start systems due for introduction next year, but unfortunately only on specific models. The aim of these models is, on one hand, to reduce the average emissions and, on the other, to conveniently slot into favourable tax bands.
For instance, Kia will launch a new ISG (Idle Stop and Go) version of the Cee'd hatchback next year. Thanks to the stop-start system and low-rolling resistance tyres, CO2 emissions drop from 145g to 137g per kilometre. That seems like an awful lot of trouble to go to for such a small gain, but in some countries it will make a difference between one tax band and another.
Reduced annual road tax aside, there needs to be a compelling reason for buyers to choose the greener models. This means that not only should there be little or no compromise, but the greener model must reward the buyer with reduced running costs. The VW Group models all return impressive fuel economy figures, and having run a Polo BlueMotion for a few months, I can report that the gains are significant, even in real-world driving.
However, there are some compromises. The longer gear ratios endow the BlueMotion and other cars with an odd low-rev characteristic, where you pre-empt a requirement for acceleration while the turbocharger spools up to speed, and eventually releases a wave of torque.
It takes getting used to, though reduced fuel bills should be enough to convince most. That aside, the most controversial aspect of many new green cars is the fitment of low rolling-resistance tyres, which certainly reduce friction, but potentially at the expense of grip - especially in wet weather.
In contrast, most of BMW's EfficientDynamics measures go unnoticed by the driver. They can choose to ignore the gearshift indicator if they wish, while the stop-start system may even be disengaged.
However, it's very useful in an urban environment and so long as you go to the effort of putting the gearbox into neutral and taking your foot off the clutch every time you come to a stop (as we are supposed to), it works effectively and restarts quickly enough to not be a nuisance.
Kia's ISG system uses identical components, while Mazda's forthcoming SISS technology restarts the car twice as quickly.
Even with the rollout of efficient new models over the next three years, it's unlikely that more than a handful of the European carmakers will manage to bring their average emissions in line with the new legislation. Drastic measures would see significant drops in the development of high-performance and luxury vehicles, fuelled by the extra costs that car manufacturers will have to pass on to the consumer.
The current economic situation will convince a large proportion of buyers to downsize in any case, which may sound like a helping hand, but the fact of the matter is that profits in small car sales have been traditionally low, and without profits the carmakers can't afford to develop the necessary new technologies.
This month the EU turned down a request from the European carmakers for low-interest loans to assist them to meet the stringent new targets. It'll be a difficult few years for the car industry, no matter what name you put on it.
Tyres Sticking to the roads
LOW-ROLLING resistance tyres are not a new invention, though their prominence has been enhanced by the increased focus on reduced emissions.
Given that as much as 20 per cent of a car's fuel consumption is due to the friction between the tyre and the road, it's hardly surprising carmakers are suddenly interested in fitting low-rolling resistance tyres as standard.
Earlier this year,
Michelin launched its latest Energy Saver tyre, which will be factory-fitted to several European cars in the bid for lower carbon dioxide emissions. The effect of the tyres is claimed to be about four grams per kilometre, which is a useful reduction.
However, Michelin has been bullish with its claims that it has now cracked the grip-versus-friction compromise; yet anecdotal evidence suggests there is notably less wet weather grip from low-rolling resistance tyres.
Until now, Bridgestone has been wary of its competitor's claims, though it too has plans for a new tyre called Ecopia.
Colm Conyngham, marketing and public relations manager, Bridgestone Ireland told Motors: "Ecopia tyres have been developed to offer lower rolling resistance while still providing excellent stopping capability.
"Bridgestone firmly believes that all reductions in rolling resistance should not compromise wet grip. Our tyre development will always reflect this."
New developments in tyre material and construction technology will aid the cause of low-rolling resistance tyres, though buyers should be made aware of potential compromises.