The Chevrolet Volt is a plug-in hybrid electric vehicle, designed to run on electricity until its battery level drops. After that, a gasoline engine kicks in to power the car. According to GM, the Volt’s battery-only range would be about 40 miles, and the gasoline engine would have about 40 mpg.

How did GM reach this inflated figure? According to Motor Trend, GM used a proposed EPA measurement system that converts a vehicle’s kilowatt hours (kWh) to an equivalent in miles per gallon. Since GM predicted the Volt would consume 25 kWh per 100 miles, they calculated 230 miles per gallon. The EPA has since shied away from GM’s claims, officially rating the Volt at 37 kWh per 100 miles and announcing it had “not tested a Chevy Volt and therefore cannot confirm the fuel economy values claimed by GM.”

Journalists questioned the 230 mpg claim because the actual figure can change drastically depending on how the Volt is driven. For instance, CNN predicts that if a driver goes 300 miles with a fully charged battery, the fuel economy would actually be about 62.5 mpg. Edmunds.com found that with the battery depleted the car averaged 31.1 mpg.  Edmunds ultimately called the Volt’s performance “seriously subpar when compared to the mid-40s mpg that a standard hybrid typically provides.”

Analysts say GM’s figures also overlook recharging and initial costs. GM has said 8 kWh are needed to travel 40 miles, which the Department of Energy says will cost around 88 cents per charge. While these costs may appear modest, reviewers like Edmunds.com question the overall value since the Volt is far more expensive than other hybrids.

Ultimately, GM and other EV manufacturers need to justify the high price tag of their vehicles by providing buyers measurable fuel savings and a return on their investment. But, even the CEO of GM has questioned the Volt’s lasting value, saying it will be “an old, old technology and old news” in just five years.

PHOTO: GM-Volt.com

The automaker even created a website named “Nissan – Zero Emission.” The image below is among the various rotating headers on the site. Are plug-in EVs really “Zero CO2″ emitters? We’ll answer that in a bit.

Nissan claims the Leaf is emissions-free

Next, Nissan asks us to imagine what the world would be like if everything was powered by gasoline. From alarm clocks to iPods to computers, the video shows us how dirty the air around us would become if it wasn’t for electricity. Renault, which has four EV models in production in Europe, created a similar ad.

None of these ads or websites makes it clear what actually sources the electricity to charge the car, however. Is it wind? Solar? Natural Gas?

Automakers are trying to define “zero emissions” vehicles as those that produce no “tailpipe emissions” in an effort to brand EVs as the greenest cars on the market. This is only part of the story, unfortunately. The following chart shows which fuels make up the average U.S. electricity grid mix.

Of course, the fuel mix for any particular region will vary, but this chart represents the average percentage of electricity sources used in America. In fact, according to the EPA, there were 24 states that used coal for 50% or more of their electricity fuel mix as of 2007.

We know we don’t have to tell you that an electric vehicle powered 50% by coal obviously isn’t a zero emissions vehicle. As more electricity comes from renewable and clean-burning sources like wind or natural gas, then PEVs can move toward becoming the environmental holy grail that manufacturers want them to be.

Welcome to Alternative Fuel Facts, where we plan to clean up the alternative fuels industry.

You see, we’ve realized that there’s a lot of misinformation floating around the internet about various alternative fuels. Industry stakeholders sometimes exaggerate the viability of and downplay the uneven playing field for technologies and fuels like natural gas (CNG), ethanol, electric vehicles, hydrogen, biodiesel, and so on.

“You mean corporations and politicians may have been embellishing the facts and figures about things that are supposed to help us?” Why, yes, it’s true.

Before you go all “you’re just saying this because you’re a front for big, bad company” on us (which we’re not), let us clear the air:

• We are not trying to say that these fuels don’t have their place in the market at all. They do. Each alternative fuel and technology has its place, has an application or applications for which it’s a great solution.
• We are advocates for propane autogas used in light- and medium-duty vehicle fleet applications, because it’s the most effective, readily-available, affordable solution for these applications.
• We think it’s ridiculous for someone to slap a “Zero Emissions” sticker on the side of an electric vehicle (EV), because it simply isn’t true. Where do they think the energy for EVs comes from?

Through our extensive research and experience in the alternative fuels industry, we’ve realized how little the general public actually knows about some of the most hyped technologies around.

• Did you know that electric vehicles like the Chevy Volt and the Nissan Leaf will be powered by electricity generated from, on average, 50% coal? And it ain’t the mythical “clean coal” variety either.
• Did you know that despite CNG having a cheap per-gallon sticker price, we’ll have to fork over $1 million+ for each fast-fill fueling station in order to fuel a (very expensive) natural gas vehicle?
• Did you know diesel fuel, chemical fertilizers, pesticides, coal-powered processing plants and oil are all parts of the process of making supposedly ‘green’ corn ethanol?