Green lite
IT would be easy -- effortless, even-- to accuse GM of bad faith in the Saturn Vue Green Line, a maximally minimal venture in hybrid powertrain technology that would seem less about fuel economy and more about securing coveted hybrid badges on the doors (and the current $650 tax credit for buyers). Unlike “strong†hybrids from Toyota, Honda, Ford and most recently Nissan, the Green Line project doesn’t deploy a gas-sipping Atkinson cycle engine; a continuously variable transmission with exotic power-routing gear sets; an electric air conditioning unit that doesn’t depend on the engine running; a powerful electric traction motor; or a large and potent advanced-chemistry battery.
It uses, instead, a big honking belt-driven starter motor that -- with a flip of polarity when the vehicle is coasting and braking -- acts as a generator, feeding electrons to a relatively dinky 10kW battery under the cargo floor. Otherwise, the Green Line powertrain is as conventional as Victorian sex. The internal-combustion smudge-pot is a 2.4-liter four-cylinder engine (a bump from the standard Vue’s 2.2 liters of displacement); the gearbox is a straight-no-chaser four-speed transmission (slightly tweaked to account for the hybrid’s transient electrical boost under hard acceleration). Unlike other hybrid SUVs, the Green Line is available only with front-wheel drive.
As much as I hate to diss any hybrid, this seems a pretty desultory effort. GM says its mild-hybrid system is cheaper and simpler than other hybrids. Well, we’ll see about cheaper, but it is simpler, in the same way “Alfie†played on a comb is simpler than the “1812 Overture.â€
Saturn is pleased to report the Vue GL’s 32 miles per gallon on the highway is the best fuel economy of any hybrid SUV. However, this is a bit of squirmy accounting. When you look at combined city/highway fuel economy, the Vue GL (29 mpg combined) actually gets five miles per gallon less than the Ford Escape FWD (34 mpg). The Vue’s combined mileage is comparable to that of the heavier and faster Toyota Highlander Hybrid and the Lexus RX400h. The disadvantage is largely due to the fact that, unlike other hybrids, the Green Line cannot move solely on electric power and so doesn’t enjoy as much hybrid benefit around town.
The salient advantage of the Vue hybrid system, says Saturn, is its low cost -- under $2,000 (the vehicle MSRP is $22,995). This is key to calculating the endlessly chewed-over hybrid premium equation, which is the additional cost of the system weighed against the potential fuel cost savings. According to Saturn, the Vue’s two-grand system rewards drivers with a 20% improvement in fuel economy. (Not to be pedantic, but by my calculations, the 2.2-liter Vue has a combined EPA of 24.5 mpg, so the improvement is numerically 17%, not 20%.)
Is this an efficiency worth trumpeting? Let’s see. According to my Jethro Bodine ciphering, the Ford Escape hybrid FWD charges a hybrid premium of about $3,300, for which you get a 28% improvement in fuel economy. So, yes, the Saturn would seem to return more fuel economy for the hybrid buck than the more elaborate Escape hybrid. Point to GM. The Camry hybrid, on the other hand, costs about $2,000 more and it returns efficiency gains of 30% (40 mpg combined). By the way, the payback period for the Vue GL is as follows: assuming $3 per gallon for gas, 15,000 miles driven annually, and a 5-mpg advantage over the conventional Vue, you’ll recoup your hybrid premium in 6 1/2 years. If you include the tax credit, the payback period is about five years.
As much fun as playing with a calculator is, let’s stow it for now and answer the question: What’s the Vue GL like from behind the wheel? Well, all things considered, I think I’d rather be under the wheels. The Vue is a tolerably decent-looking trucklet, to be sure, especially in hybrid trim, which comes with alloy rims and appealing “skid-plate†brightwork fore and aft. The formerly tragic, plastic-harlequin interior has been upgraded to a restrained and well-organized cabin. The GM-standard switches, audio and climate panel and instruments are all fine, although it would have been nice to have an instant mpg readout in the panel (there is an “Eco†light to inform you when you’re attaining EPA-nominal mileage).
What I can’t believe, can’t forgive, is how astoundingly cheap some parts of the car feel. The gearshift is loose and wobbly, the doors shudder when they are closed. It feels like the interior was snapped off from a plastic tree a la Revell model. My God, did everybody in vehicle validation wear mukluks?
The unibody chassis felt stiff and stout; this quality, unfortunately, only served to highlight the loud and poorly damped suspension, which rattled and boomed when it encountered ordinary road roughs. And when I hit the raised seam of asphalt at the end of my block, the entire vehicle shook like God’s own beagle had me by the scruff.
Also, because the air-conditioning unit runs off the serpentine belt -- not electrically -- the A/C compressor cuts off when the engine shuts down at stops. On hot days, drivers may be obliged to click off the ECON A/C button, which will prevent the engine from cutting off. Kind of defeats the purpose of a stop/start hybrid, though.
In acceleration from 0 to 30 mph around town, the Vue GL was passably spry, even if it did sound as if it was going to split its pants in the process. About 48 foot-pounds of torque from the starter/generator are available to boost the engine. Zero-60 mph time is approximately 10 seconds. At higher speeds, urgent summons to LaForge in Engineering were answered with static. The vehicle is comfortable cruising at 70 mph and slightly miserable at 85 mph.
Though you probably couldn’t tell it so far, I have mixed emotions about the Vue GL. For one thing, a simplified, stop-start hybrid system could be a model for the industry. There’s no reason an engine needs to be idling when the vehicle is stopped, not when there are electric versions of accessories such as power steering and air conditioning, and when semiconductor processing to manage it all is so cheap. If this car helps support a generalizing of this technology through the GM fleet, I’m all for it. In the meantime, the Saturn division will press ahead with plans to install the Green Line quick-and-dirty hybrid system in the new Aura sedan (no word yet on price).
Is it all marketing and greenwashing? Perhaps, but I wouldn’t rule out a sincere difference in opinion, either. GM execs -- and most vocally Vice Chairman Robert Lutz -- were never enthusiastic about hybrid powertrains in passenger cars. They argued, quite reasonably, that hybrid powertrains could best acquit themselves in large SUVs and trucks, where even small gains in fuel economy could add up to oceans of unburned gasoline. Indeed, next year we will see full-on, duel-mode hybrid systems in GM’s biggest boats. If and when that occurs, I will sacrifice a biblical ram in their honor.
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2007 Saturn Vue Green Line hybrid
Base price: $22,995
Price, as tested: $25,000 (est.)
Powertrain: 2.4-liter, 16-valve, DOHC inline four-cylinder engine with variable-valve timing and hybrid electric assist; four-speed automatic transmission; front-wheel drive
Horsepower: 170 hp (combined gas and electric)
Torque: 128 pound-feet
Curb weight: 3,420 pounds
Wheelbase: 106.6 inches
Overall length: 181.3 inches
EPA fuel economy: 27 miles per gallon city, 32 mpg highway
Final thoughts: More chartreuse than green
