The 2011 Chevy Volt, the hybrid car that General Motors Co. hopes will wow the world with its total greenness, will get 230 miles per gallon, the company said last week. These sites check the claim.

Plugging Volt. When we looked, this Volt-boosting site, which says it is not affiliated with General Motors, was leading with a post on how GM arrived at the 230 m.p.g. designation. The most telling comment by a GM official is that if the Volt is never driven beyond the battery's 40-mile range before recharging, the gasoline mileage number is "infinite." Accounting for the energy used by charging the battery "will get melded in another way and is not included in the m.p.g. estimate," the site says.

http://gm-volt.com

Volt discharge. GM's forthcoming electric hybrid car might get a gas-mileage number of 230 per gallon, but its estimated price tag of $40,000 means it's not likely to be a great deal, compared with other hybrids, according to this entry at WalletPop. The blog entry is based on an item from the car site edmunds.com, which is famous for calculating what it calls the "true cost" of owning vehicles.

http://go.philly.com/walletvolt

The edmunds.com information is presented as a graph. "Anyone who thinks that 230 m.p.g. means inexpensive might have to recalibrate their expectations," the site says. Of course, for many prospective owners, cost may be less important than the environmental impact. On that, the page contains an animated - and ongoing - discussion by readers.

http://go.philly.com/edmundsvolt

Volt review. The Consumer Guide section at HowStuffWorks.com published this review material about the Volt earlier this year. You can visit to compare the Volt with its presumed competition, including the Toyota Prius, Ford Fusion, and Honda Insight. As to price, the site says: "Apparently . . . GM underestimated the cost of the high-tech batteries and other Volt-specific components. The wild card is whether the company might be willing to take a loss by subsidizing the price down to the original $30K target - and if so, for how long."

http://go.philly.com/howvolt

Contact staff writer Reid Kanaley at 215-854-5114 or rkanaley@phillynews.com.