HENRY PAYNE

Payne: Plug-in electric Volt or natural-gas Impala?

Henry Payne
The Detroit News

The 2015 Chevy Impala natural gas-assisted, gasoline hybrid has a range of about 545 miles. Which is a good thing because that’s how far you may need to drive to find a natural gas filling station.

The closest one to my Oakland County home was 38 miles away at a DTE Energy depot on French Drive by Detroit City Airport. It’s not a neighborhood I would advise the missus to drive to every day. Take a right at Graffiti and Empty-Lot-With-Tall-Grass, then it’s the first right past the empty building with “FILTHY FRESH” spray-painted on the side.

The security guard behind the barbed-wire fence will let you in.

But you can fuel it at home if yours is one of 50 percent of U.S. residences powered by natural gas. That makes natural-gas hybrids a viable competitor to battery-powered electric vehicles for convenience.

Plug-in electric hybrid or natural-gas hybrid? Chevy offers both, so I compared the 2016 Chevy Volt to the Impala to answer which is the King of Convenience.

Greenies say the future has a plug and have touted electric vehicles for their alleged zero CO2 emissions. The truth is more complicated. Lithium-ion batteries take an enormous amount of energy to produce, contain toxins and get their juice from a carbon-based energy grid. Recent academic studies have found that — over the life-cycle of an EV in the coal-powered Midwest — it would actually increase CO2 emissions.

Just as utilities seeking to affordably reduce their carbon footprint have turned to natural gas, so have automakers looked at compressed natural gas as an alternative. Their carbon dioxide emissions are 75 percent of gasoline-powered equivalents. Thanks to America’s fracking boom, the cost of natural gas plummeted in recent years, leading to GM’s ambitious plans for the Impala — only the second compressed natural gas vehicle on the market after Honda’s Civic.

But fracking also benefited the oil market, meaning my CNG Impala cost $2.64 to refill down by the “FILTHY FRESH” in November when gas prices were just $1.89 at my local BP station (now $1.59). Ouch. But what if I could fill up at home?

The convenience of a garage-installed natural gas station — called The Phill by BRC Fuelmaker — would set me back $5,500. Double ouch. After that heavy lift, refilling the Impala’s 7.8-gallon natural gas tank is a bargain at about 92 cents a gallon from home — if you’re patient. At a half-gallon an hour, she’ll take 16 hours to feed.

With residential rates a mere 8 cents per kilowatt hour (just 3.7 kWh at night), the Volt has the CNG beat on cost, if not convenience. My Volt tester took a CNG-like 13 hours to recharge on a standard 110-volt outlet at a cost of about a buck. Forget to plug in one night when your arms were full of bags? Both Chevys will take half a day to top off when you realize you left them unfueled next morning (happily, gasoline backup is always ready).

Want to cut that in half? DTE Energy says you can buy a $500 (plus $2,000 installation) 240-volt charger for the Volt.

But don’t be so sure Volt will get its advertised 53 miles on a charge in Michigan winter. I got 30 mpg around town. Sure, I was lead-footing it (stomping Corvettes out of stoplights with instant electric torque is addicting). But even in good-boy, hyper-miling mode, I managed just 37 mpg.

The CNG Impala offers consistent fuel mileage regardless of temperature. Toggle the CNG button on the left dash and the car draws its power from the extra tank behind the rear seat. My CNG mpg nearly matched gasoline (26 mpg vs 27) — and I got a range of 149 miles. When the tank runs out the car switches imperceptibly to gasoline just like the range-extending Volt. Total mileage? 545 miles compared to the plug-in’s maximum of 293 in balmy weather.

Advantage Impala. But wait, there’s more. My two testers will set you back $38,210 (Impala) and $34,475 (Volt).

Throw in the $7,500 EV federal tax subsidy for saving polar bears and the compact Volt is a whopping $11K cheaper than the full-size Impala. That savings, however, will get you a lot less car. Impala’s acres of seat room easily fit five polar bears. Thanks to a smaller battery, the ’16 Volt can now seat five — if the middle, back-seat passenger is a Barbie doll.

When Volt’s charge runs dry you’re left with a buzzy, 1.4-liter four, whereas Impala gets a powerful V-6. Going bi-fuel, however, means less-powerful port-injection versus the standard Impala (260 vs. 305) — and more pounds (375) to carry.

A generation ago you would have had to put a gun to my head to plug Impala. It was the bane of rental fleets. On a recent trip to Dollar Rental, I was reunited with Impala Sr. and it was as undistinguished as I remember.

The Impala is all you have? NOOOOOOOOO! Check the key bin again!

The 2015 model, however, has been transformed. Like the Volt, its user-friendly interior is state of the art. My 2015 model didn’t have the Apple Car Play connectivity of the Volt, but it’ll come. Impala’s Extreme Makeover gives it a welcoming, pretty face and voluptuous hips.

It also exposes Volt’s biggest mistake: down-market styling. In the 30-grand neighborhood where it rubs shoulders with Impalas and sexy, small luxe rides, the chrome-beaked Volt looks like a $20K Chevy Cruze. A Cruze with bling, sure. But still a Cruze.

I won’t deny the status factor. I got in more conversations with green cuties driving the Volt than I did Impala — which only betrays its green-ness with a big “CNG” sign on the trunk.

Whaddaya got there? A DTE fleet vehicle?

The Volt’s driving dynamics benefit from the floor-mounted battery’s low center of gravity. But the big Impala is no slug with a substantially stiffer chassis than the old rental dinosaur. Its CNG tank works against its natural advantage — space — by taking up half the trunk, meaning its 10 cubic feet of cargo room is just shy of the hatchback Volt.

The verdict? That green halo never comes cheap. All things considered, the CNG Impala is more practical family transportation even as the Volt will save you in the wallet.

Henry Payne is auto critic for The Detroit News. Email him at hpayne@detroitnews.com. Follow him on Twitter @HenryEPayne.

’15 Chevrolet Impala

Vehicle type: Front-engine, front-wheel drive, five-passenger sedan

Price: $38,210

Powerplant: 3.6-liter, dual overhead cam V-6

Power: 260 horsepower, 247 pound-feet of torque (using gasoline); 230 horsepower, 218 pound-feet of torque (CNG)

Transmission: Six-speed automatic

Performance: 0-60 mph (NA)

Weight: 4,175 pounds

Fuel economy: EPA 17 mpg city/25 mpg highway/20 combined (using gasoline); EPA 16 mpg city/24 mpg highway/19 combined (CNG)

Report card

Highs: Fuels at home just like an EV; acres of room

Lows: Convenience home filling station an inconvenient $5,500; CNG tank means less trunk room

Overall:★★★

Grading scale: Excellent ★★★★Good ★★★Fair ★★Poor ★

’16 Chevrolet Volt

Vehicle type: Front-engine, front-wheel-drive, five-passenger sedan

Price: $33,995 base ($34,475 as tested)

Powerplant: 18.4 kWh, lithium-ion battery driving two electric, AC motors plus 1.5-liter, dual-overhead-cam, inline 4-cylinder

Power: 149 horsepower, 294 pound-feet of torque (in electric mode); 101 horsepower (gas engine mode)

Transmission: Continuously variable automatic

Performance: 0-60 mph, 8.4 seconds (manufacturer)

Weight: 3,543 pounds

Fuel economy: EPA 106 MPGe (combined electric/gas); 43 city/42 mpg highway/42 mpg (gas engine only)

Report card

Highs: High-tech interior; good handling, low center of gravity

Lows: Range suffers in polar bear weather; only a bargain as long as $7,500 subsidy lasts

Overall:★★★