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Two cars launched in Auckland within the past 24 hours point to the start of a new generation of fuel-saving technology for internal combustion engines that German component specialist Bosch says is more efficient than petrol-electric hybrids.
The two-door BMW 1-Series coupe and convertible that go on sale here in the first week of June won't have the technology - but later models will, although BMW New Zealand is not sure when.
One of the technologies only works with lean-burn engines running on petrol with a maximum sulphur content of 15 parts per million. The 50ppm of sulphur in New Zealand petrol is too high. BMW - and other carmakers - will leave this country out of the latest cleaner-burning technology loop until the fuel is cleaner.
The Marsden Pt refinery is working on reducing sulphur content in petrol but the Government has been criticised for dragging the chain. Sulphur in diesel, however, will be reduced to 10ppm next year. In theory, high-tech diesel cars only will be able to take full advantage of the technology - for the next few years at least.
Stop-start and brake energy regeneration is part of BMW's "efficient dynamics" technology, a package of engine add-ons and equipment upgrades often referred to as mild hybrids. Brake energy regeneration is already available here on the high-performance BMW M3 range.
Stop-start is the fuel-critical system. It switches off the engine when the vehicle is stationary, like at traffic lights. Brake energy regeneration harnesses energy lost during braking. BMW says combining both technologies cuts fuel consumption and CO2 exhaust emissions by between 8 and 15 per cent.
Bosch developed stop-start for BMW and chairman Bernd Bohr says it is cheaper and more efficient than hybrid technology. He expects it to make up 20 per cent of the European market - one in five cars - by 2015. Citroen is a user while Mercedes Benz is about to introduce it as Europe has less sulphur in its fuel than this country.
Stop-start is available only on 1-Series BMWs with manual gearboxes. The 3-Series and 5-Series manuals are expected to get it in Europe soon as are the manual Minis. Adapting it to work with automatic transmissions is trickier. "It is a work in progress," says a BMW engineer.
The advantage of stop-start is that it's relatively cheap to make and simple to apply. It works like a petrol-electric hybrid but without that type's expensive and weighty battery pack.
Stop-start is one of the reasons why hybrids do much better in city driving rather than on the highway.
Bosch has developed a high-tech starter motor to manage the system. Volkmar Denner, of Bosch's management board, said: "Incorporating stop-start requires no other change to the vehicle's drive train or the engine. The system delivers an excellent cost-benefit ratio, making it attractive compared with alternative solutions.
"The number of engine starts the system has to make, its service life, has been increased significantly for this application.
"Despite the increased number of functions, the starter is compact and can be integrated into the vehicle just as easily and conveniently as other starter motors."
Stop-start automatically switches off the 1-Series engine when the clutch is disengaged below 3km/h and the gear lever is in neutral. Depress the clutch to select first gear and the engine fires up again.
Brake energy regeneration uses a smarty-pants alternator. A regular alternator converts power from the engine to the battery, to keep it fully charged to run electrical functions. That's pretty much its lot. Going fast or going slow, it's all the same to the standard alternator.
The 1-Series alternator, however, recognises engine load. When the car is under the throttle, it stops what it's doing to allow the engine to direct every watt of its oomph towards dynamic efficiency. Under braking, it re-engages to charge the battery - in effect to harness energy lost during engine over-run. This is the first time the technology has been used in a non-hybrid vehicle and BMW says it improves fuel consumption 3 per cent.
It first appeared in 1967 in a battery-powered experimental car called the Electron, built by American Motors Corporation. The idea then was to charge the batteries as the car slowed down, thereby achieving longer battery life between plug-in charges. Forty-odd years on, the principle still applies.
BMW and Bosch say the important feature is that these technologies further improve the internal combustion engine without the drawbacks suffered by other green technologies.
BMW, holder of the World Green Car of the Year award for the turbodiesel 1-Series 118d, reduced its emissions last year faster than any other carmaker, says an independent British-based study.
Four of the efficient dynamics technologies, including stop-start and brake energy regeneration, helped the 118d win the award.
It is the most fuel-efficient car BMW makes. The technology reduced consumption from 5.6 litres/100km (50mpg) to 4.7 litres/100km (60mpg) and CO2 exhaust emissions to 123 grams a kilometre, all while boosting engine power by 17 per cent to 106kW. The closest engine to it available in New Zealand is the 2-litre unit found under the bonnet of the 1-Series 120d hatchback. It is rated at 128g/km.
Only a handful of cars here can better that such as the Toyota Prius and Honda Civic hybrids, a Smart model and the Volkswagen Polo hatch. The Government wants a CO2 ceiling of 170g/km by 2015 for all vehicles under 3.5 tonnes.
BMW says the new 1-Series coupe and convertible are typical examples of efficient dynamics, even without stop-start and brake energy regeneration.
The company's New Zealand chief says: "We have a long-term strategy for sustainable mobility that was put in train long ago and exists across every single one of our vehicles. Now, each new model launch puts us another step ahead of the pack.
"In this highly competitive market, we can no longer rely on organic growth. We need to be precise in responding to customer demand and, in some cases, manufacture desire through ground-breaking new products."
Both rear-drive vehicles offer the 2008 World Engine of the Year, a 3-litre twin-turbo straight-six petrol unit lauded for its power and fuel efficiency. Other engines in the line-up include 2-litre four-cylinder petrol and diesel units.
The top-range 135i coupe and convertible get the winning 3-litre engine. It develops 225kW (306bhp) at 5800rpm and 400Nm of torque between 1300-5000 rpm. BMW claims a zero to 100km/h sprint time of just over five seconds and a top speed of 250km/h. Town and around fuel economy is a claimed 9.2 litres/100km (30.7mpg) and CO2 exhaust emissions are rated at 220g/km.
The other petrol engine, a 2-litre unit producing 115kW at 6400rpm and 200Nm at 3600rpm, is available only in the entry-level 120i convertible.
The turbodiesel powerplant is confined to the 123d coupe. It's a 2-litre unit producing 150kW (204bhp) at 4400rpm and 400Nm between 2000-2250rpm. Top speed is 238km/h and fuel economy a claimed 5.2 litres/100km (54.3mpg). CO2 emissions are rated at 138 g/km.
Both coupe and convertible come with up-to-the-minute safety equipment and everything that opens and shuts. The soft-top even gets leather seats and armrests that don't absorb the heat of the sun. It's a comfort thing.
The 120i soft-top starts in price at $56,000 and the 135i at $86,500. The 123d coupe is priced from $62,000, and the 135i coupe from $78,500.
