If you need a plug-in car that is capable of traveling long distances between charges but can’t afford the 300-miles per charge option offered by the 2012 Tesla Model S, the chances are you’re looking at buying a plug-in hybrid. 

But which of the two main plug-in hybrids on offer today -- the 2012 Chevrolet Volt and 2012 Toyota Prius -- offer you the cheapest running costs, and why? 

As we’ve said before, that depends on how often you make longer trips, but now Pike Research has stepped in with the definitive answer

The 2012 Toyota Prius Plug-in Hybrid is more cost effective on trips over 70 miles. 

Assuming a gasoline price of $3.50 per gallon, electricity at 11 cents per kilowatt-hour, the 2012 Chevrolet Volt wins hands down on trips up to 30 miles in length thanks to its ability to travel up to 35 miles on a single charge without turning on its gasoline engine. 

But once its on-board battery pack is depleted, the Volt is barely better than the 2012 Ford Escape Hybrid FWD on fuel economy at just 35 mpg, while the 2012 Toyota Prius Plug-in Hybrid gets nearer 50 mpg when its smaller battery pack is out of juice.

2012 Toyota Prius Plug-in Hybrid

2012 Toyota Prius Plug-in Hybrid

In other words, the Toyota Prius Plug-in Hybrid may have a lesser range in all-electric mode, but it has a more efficient gasoline engine. 

For trips longer than 70 miles where there’s no-where to plug-in, the cost of running the 2012 Chevrolet Volt increases dramatically, costing $8 to travel 100 miles rather than the $7 it costs in a 2012 Toyota Prius Plug-in Hybrid.

Don’t forget though that we’re talking about regular trips above 70 miles. To truly understand which car will cost you more to run you have to examine just how many of your trips are over that magic 70 mile barrier. And as gasoline and electricity prices change, the delta between the two in terms of cost will also change. 

Our advice: If you really do need a longer-distance car that can operate as a pure electric vehicle around town, examine your driving patterns before buying. If you rarely go beyond 70 miles per trip or have somewhere to plug-in, the Volt wins hands down on cost. 

But if you need to make regular, longer trips, the lower price of the 2012 Toyota Prius Plug-in Hybrid -- combined with its ability to travel in HOV lanes in some states -- could give you the cost-saving edge over its Chevy competitor. 


Follow GreenCarReports on Facebook and Twitter.