Japanese automaker Toyota has fired a warning shot across General Motors’ bow today with a revised set of gas mileage figures for the soon-to-be-launched 2012 Prius Plug-in Hybrid. 

Announced by Toyota Division Group Vice President and General Manager Bob Carter, official economy figures in electric-only mode have been improved from 87 miles-per-gallon equivalent (MPGe) to 95 MPGe.

On paper, that makes the 2012 Prius Plug-in Hybrid get better economy in electric-only mode than the extended-range Chevrolet Volt, which has an official electric-only rating of 94 MPGe. 

In hybrid mode, Bob Carter said the 2012 Prius Plug-in Hybrid would be rated at 50 mpg combined, up from Toyota’s previous 49 mpg estimate and a full 13 mpg better than the more expensive Volt. 

2012 Toyota Prius Plug-in Hybrid

2012 Toyota Prius Plug-in Hybrid

Although we believe the figures have yet to be officially approved by the Environmental Protection Agency (EPA), Toyota now appears firmly in the plug-in vehicle market. 

Sadly though, real-world comparisons aren’t as simple as comparing two different figures. In this case particularly, it’s much harder.

For a start, there’s cost. Starting at $32,760, Toyota’s five-seat Prius Plug-in Hybrid is much cheaper to buy than the $39995 four-seat, base-level Chevrolet Volt.  

But while the Chevrolet Volt is eligible for the full $7,500 federal tax credit towards its purchase, the 2012 Toyota Prius is only eligible for a $2,500 federal tax credit. 

Then there’s range. While the 2012 Chevrolet Volt will travel an EPA-approved 35 miles per charge at highway speeds, the 2012 Toyota Prius Plug-in Hybrid will only travel 15 miles per charge. 

On top of that, electric-only operation in the Prius is limited to 62 mph or less. 

Which car is really the more efficient? That’s tougher to say. 

Toyota Prius Plug-In

Toyota Prius Plug-In

As we’ve proven before, the 2012 Prius Plug-in Hybrid is more efficient than the 2012 Chevrolet Volt on trips longer than 70 miles, but if the majority of your daily driving is over 15 miles and under 35 miles in length, the Volt is a better choice. 

Ultimately, real-world mileage for both vehicles will depend on how much you plug in versus how much you use the gasoline engine -- not to mention your individual driving style and the roads you drive on.

Don’t think the MPG war is over yet either. 

With Ford promising its 2013 Fusion Energi plug-in hybrid will get over 100 MPGe and Chevrolet bound to respond with improved economy figures for the 2013 Volt, the battle for plug-in hybrid supremacy has only just started.

It’s time to sit back and enjoy the show. 


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