Determining the Range of the Chevrolet Volt

The EPA has yet to figure out how to rate the 2010 Chevy Volt's EV range or fuel economy, so we devised our own method. We charged the battery three times and used three different drivers and three different driving routes to get an estimate of the Volt's EV range. One caveat, however. Your range will vary depending on the use of interior heat or a/c, the driving load and speed. The range depends on the three Ts: temperature, technique, and terrain. Here's what we learned.

Charge #1
After a 11-hour overnight charge using the cord stored in the cargo area and a 120-volt outlet in our garage (a 240-volt charger will sell for $490 before installation and will drop the recharge time by at least half), we set out to maximize EV range. The dash display said we had 48 miles of EV range, which dropped to 43 after the first quarter mile. It must have known of our usual lead-foot nature. We turned off the climate control, which wasn't a problem since the outside temperature was roughly 55 degrees. Our route meandered through Ann Arbor and the surrounding two-lane country roads. Our hypermiling skill is clearly lacking: After 31 miles the engine kicked on.

Charge #2

For the second charge, we stuck to city streets but operated the car normally, with the auto HVAC operating and without special driving techniques. We must have recaptured more braking energy in the city streets than the previous day, because the Volt traveled 35 miles on just the battery.

Charge #3

Finally, we drove the Volt for nearly 600 miles on the highway only, a tough test for any hybrid since there's no opportunity for brake regeneration. Also, we set the cruise at a typically brisk Michigan highway traffic speed—78 mph. Still the Volt's EV range beat that first day when we were really trying: 33 miles.

Average EV range: 33 miles

Fuel Economy

In addition to measuring EV range, we also recorded the fuel use when the car was in its “charge sustaining" mode. In other words, we computed the fuel economy after the battery was depleted, both on our city loop and the highway trip. In the city, we recorded 31.67 mpg and achieved 36.0 mpg on the highway. If we factor in the distance traveled on the battery's energy the fuel economy jumps to 37.5 mpg city and 38.15 mpg highway.

The Bottom Line

After our three days with the Volt, we're certain of a few things: One, the car is a well-engineered piece that integrates the various powertrain components with a refinement we didn't expect. Except for some of the materials, the interior cocoon fits a $41,000 car, which in practice drops to $33,500 after the $7500 federal EV subsidy. As for the rather unremarkable fuel economy, it's useful to remember that the Volt carries two powertrains—electric and gas—and thus suffers a weight penalty that effects overall efficiency. But of course, those two powertrains are why the Volt can be a primary vehicle that doesn't ask the owner to compromise driving cycles like a pure EV. Consider the Volt a well-engineered first step on the path to electrified vehicles.



Source: Popular Mechanics