Apparently, 2011 was the year when green technology started to take hold, or so we're led to believe. An electric vehicle, the Nissan Leaf, took out not one but virtually all of the most prestigious car awards in 2011, including the European, Japanese and also the World Car of the Year titles. Why? Mainly because it drives like a regular car, but is zero emissions. Perhaps all these accolades are a little premature, however, as sales of EVs globally have disappointed - scarcely surprising given their high cost, limited range, and not-so-fast recharge times. Moreover, battery technology is still in its infancy. With these issues, EVs won't reach critical mass anytime soon.
In the meantime, green-tinged cars will prove increasingly popular, but many of these, particularly the petrol-electric hybrids, are unexciting drives. However, two recent newcomers have been designed both to optimise fuel consumption and to be a pleasure to drive.
Mazda is under pressure to produce "sustainable zoom-zoom" cars. Is this a bridge too far? Maybe not, if the first of its SkyActiv vehicles to arrive here, the Mazda3 GSE, is any indication. With clever combustion chamber design, its 2.0L high compression (12:1) direct injection engine still manages to run merrily on 91 unleaded fuel. Power output is up a few kW and Nm compared with the regular 2.0L engine, but fuel economy falls by a substantial 26 per cent. Thank to improvements in air management in part for this, and also use of idle-stop technology, but most is attributable to engine design, and also a new lightweight, low-friction, six-speed automatic transmission.
How goes it? Truth be told, it doesn't feel substantially different from the GSX model. Perhaps a touch faster thanks to its quicker-shifting auto, and it's still near to top of its class dynamically. Fuel use? Going at a reasonable clip, it used in the 7s (L/100km), which is not bad considering. And cruising at 100kmh, well into the 5s is possible. While performance overall is pretty good, you have to be prepared to work the throttle reasonably to extract it, and that's something we've noticed recently of others aiming for improved fuel efficiency. The transmission has no Sport mode, tellingly, and no paddles; if you want decent performance you're best off using lots of revs and shifting manually. I prefer the ease of delivery from a lower displacement turbocharged engine, like that of the Holden Cruze 1.4 SRi, for example. Not quite the fuel economy, mind you. In town, the Mazda feels quite frisky because the engine torque is beefed up at low revs; it handles fifth gear at 50kmh no problem.
Meantime, Honda has another take on fuel efficiency that's quite different from Mazda's; its Integrated Motor Assist technology consists of a petrol-electric hybrid, but operation can be varied to optimise fuel efficiency, as in the Insight, or to optimise performance (or even both), as in its new CR-Z coupe.
CR-Z is essentially CR-X reborn for a new era - it even uses old styling cues - where fuel efficiency is increasingly important. The CR-Z is like two cars in one. In normal mode, it slopes around town energetically enough. At the push of a Sport button, a small electric motor (10kW/76Nm) adds urge to what is essentially the 1.5L Jazz engine. At lower revs it feels as though there's a turbo assisting when the electric motor kicks in, and at higher revs it offers that traditional twin-cam VTEC surge.
Unlike with other hybrids, the NiMH battery pack is tiny, weighing under 30kg, including all its electronic control bits and pieces. It fits under the luggage floor, and is said to help improve weight distribution, though at a measured 60/40 front/rear, this figure is nothing out of the ordinary for a front-driver. Weight overall is decent enough, at 1154kg for the manual. And fuel efficiency is even more so, a claimed 5.0L/100km overall for the six-speeder, and 4.7L/100km for the CVT version.
What's especially entertaining is how this eco-hot-hatch runs. Evidently, a Lotus Elise was used for benchmarking. The chassis is a shortened version of the Insight's. So essentially you've got the backbone of an eco-hybrid and the petrol engine of a supermini. Doesn't sound like a recipe for fun really, does it? Nor does a 0-100kmh time of 9.2sec. Yet, despite everything, this little eco-warrior can deliver a surprisingly satisfying and sporty drive experience, especially but not exclusively the manual. It's sharp enough that Wheels magazine awarded it Car of the Year status. Unfortunately, it's not that cheap here, at $44,900 for manual or auto variants, especially as it's essentially only a two-seater.
Finally, on the zero-emissions front, a promising eco-option that's come from left field has the potential to make life even harder for EVs. Compressed-air cars are already available overseas but are noisy and performance is ordinary. Now British engineering firm Ricardo is developing a new form of liquid (cryogenic) compressed-air engine technology. The Dearman engine operates by injecting liquid air into the "combustion" chamber, rapidly producing superheated high-pressure gasous air, and this energy release drives the engine. The system is said to be cheaper than alternatives, safe, producing zero emissions, and offering excellent energy density, fast refuelling and a good touring range. Ricardo and Dearman are working together to market the technology.
» Follow NZStuffBlogs on Twitter and get fast updates on all Stuff's blogs.
Post a comment