Greenwashing is the new power race

Here's something you're probably never going to hear: "Well, we've done the rounds of the showrooms, we've done the sums and we've narrowed it down to a choice between a Prius and a smart fortwo."

The Carsales Network welcomes the latest wave of greenwashing, but really, all this jockeying for title of Australia's Most Fuel-Efficient Car is the greenwashing furphy du jour.

It has never been a standalone criterion on which consumers buy cars, and it never will be. The same could be said for earlier campaigns targeting safety and performance too. It's how the public allegedly perceive the importance of fuel efficiency that's the driving force behind all the posturing we're seeing from auto marketers -- for the apparently coveted title of Australia's Most Fuel-Efficient Car.

Witness Ford's current campaign depicting a pretty lady parking a Fiesta ECOnetic in front of a billboard showing the Prius beneath said title. It takes over where MINI left off last year, trumpeting the same claims against the last Prius, when it launched the Cooper D in mid 2009. That was until Toyota's next generation Prius matched the MINI's state-approved claims of 3.9L/100km.

So where do they get these figures from? Manufacturer claims hail from laboratory dynamometer testing conducted according to stringent Australian Design Rules standards and conditions. These are audited by the federal transport department.

The two-phase, 20 minute test cycle covers 'urban' (city) and 'extra-urban' (open highway) conditions. The former emulates high-traffic city conditions -- an average speed of 19 km/h, 30 percent of testing time spent at idle, with frequent stopping and starting. The latter attempts to emulate driving conditions out of town. Not the perfect freeway run, on which the car could sit on a steady 110 km/h, but something more realistic, with the vehicle averaging 63 km/h and peaking at 120 km/h, with fewer stops and starts.

Most vehicles consume more fuel on the city cycle. But for petrol-electric hybrids like the Prius, it's the opposite. They're often at their best in bumper-to-bumper conditions, because wherever they can, they skew the power output mix towards the electric motor on take-off, with the petrol burner cutting in once the momentum is up. That means, under realistic conditions with an ordinary driver at the wheel, they will often be more fuel-efficient than their diesel 'competitors'.

But let them off the leash down 100 kilometres of open freeway and the diesels are in their element. Cars like the Fiesta Econetic and BMW's 118d are set up to get you through the low gears as quickly as possible after taking off; once you're off and running, all that low- and midrange torque comes into play, after which they'll sit happily in fifth and sixth, maintaining very low revs uphill and down dale, hour after hour.

It's this horses-for-courses factor that renders such campaigning spurious. More so once the vehicles competing for the title are split into appropriate categories of size, shape, price bracket and intended use. More so again once you start factoring in annoying variables like consumer tastes, lifestyle and disposable income.

We recently spent a fortnight in Lexus's LS600hL, a hybrid limo with the interior space of a warehouse, laden with enough reclining massage chairs, air conditioning compressors and in-house entertainment to see it weighing in at a consequential 2.3 tonnes. Most remarkable, then, was the 10.5L/100 km it averaged through about 1500 km of mixed city, freeway and country driving. With nary a moment's care on the part of the driver.

Anyone taking a realistic look at the private car market would give the big Lexus a spot among Australia's most fuel-efficient cars.

It's extremely unlikely that anyone will ever be found tossing a coin between the Prius and the Fiesta. The Toyota is a family car, or close to it. The Fiesta is not, but at least it's half way to a genuine four seater. At around $25,000, it is, however, anything from $10,000 to $25,000 cheaper than a Prius, depending on spec.

The Mini Cooper D is a genuine four-seater -- provided the front seats are occupied by persons no larger than 150 cm tall, and the rear seats are occupied by persons no larger than their handbags. At entry level, it costs as much as a base Prius, (mid-$30s) but can be optioned up to cost about as much as a Lexus LS600hL [Ed: Not really, but we get what you mean, Jeremy].

In short, then, what's the likelihood there's anyone out there fretting over the choice between a Prius, a Mini D or a Fiesta Econetic? Zero.

But in its necessary complexity, a realistic view of the auto market presents advertisers with a problem. Namely, what sounds better: "Australia's Most Fuel Efficient Car"? Or "Australia's Most Fuel Efficient Petrol-Powered Four-Cylinder Four-Door Five-Seat Luxury Saloon"?

And on a related matter, don't get us started on just how important it is to reach Sydney from Melbourne on one tank of fuel -- with all the safety campaigns targeting fatigue on long journeys and the likelihood you'll have kids in the back demanding toilet breaks and 'happy meals' along the way.

Back to the question of "Australia's most fuel efficient car", it looks set to get more troublesome for the car companies yet. If it goes to market -- which, as the Carsales Network reported recently, looks increasingly likely every day -- Porsche's sub-3L/100km hybrid 918 Spyder will probably smother the whole silly shemozzle. Because in that event, you'll need anything from Sydney median house price money to a million bucks to get behind the wheel of Australia's Most Fuel Efficient Car. How important will the title be then?

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