It is that time of year - the car commercials on TV have left the 2007 models in the dust and are speeding head-on into the 2008 editions. If you’re thinking about buying a car in 2008, here are the top five greenest vehicles out there based on EPA standards.

Tesla Roadster http://www.teslamotors.com/

If you’ve got the dough, opt for the Tesla Roadster. Tesla Motors is now accepting reservations for owners of this high-performance all-electric roadster. Unfortunately, while you can buy a Roadster in 2008 (they’ll take your money any time you’re willing to part with it) the actual 2008 models are already sold out. Anyone getting on their list will have to stay on the bus until 2009. Keep an eye on them though, they’re working on a sedan with the same electric design that will retail at only $50k – much more reasonable for the average Joe. Due to the youth of the company, they’ve not yet been tested by the EPA but as all-electric vehicles they make absolutely no emissions.

Toyota Prius http://www.toyota.com/prius/models.html

Toyota continues their ongoing success with this, the first mass-market hybrid. The 2008 Prius offers many options on customization and is something you’ll actually be able to get your grubby little paws onto for a test drive. This year the Prius ranks not only a 9.5 (out of 10) on the EPA’s emissions test but also gets a perfect 10 on the greenhouse gas score. Congratulations to Toyota on continuing the high level of quality. With an estimated 45/46 estimated MGP this beauty will also be kind on your gas bill and leaves all the other Hybrids on the market wishing they knew what was under the hood.

Nissan Altima Hybrid http://www.nissanusa.com/altima/specifications.html

Neck – in – neck with the Toyota Prius is the new Hybrid from Nissan. This year’s model sports an appealing 35mpg rating and 9.5 emissions score with a 9 on the greenhouse gases. While Nissan is definitely on the right track here there is some bad news to green drivers, this Altima will only be available in select states that offer a tax incentive on the purchase of this type of vehicle.

Honda Civic CNG http://automobiles.honda.com/civic-gx/

The only reason I rate this natural-gas powered vehicle as fourth instead of third (it is actually more fuel-efficient than the Altima) is due to the limited supply of fuel available. Honda has developed a fuel-at-home device that you install into your garage for overnight fueling, but unless you live in California where there are CNG pumps, this option is about as practical as the Tesla for the average consumer. Being one of the first mass-produced CNG vehicles was bound to be a rough road, and this Civic will be one to watch in the years to come.

Mercury Mariner Hybrid http://www.mercuryvehicles.com/mariner/

For those who love their SUVs there is one hybrid SUV that performs well enough to make this list. Enter the Mercury Mariner Hybrid. It sports a 9.5 on the emissions and a 9 on the greenhouse gasses, the minimum for this list, but what actually put it over the top was its fuel efficiency. This two-wheel drive sports a 34/32 MPG estimate. If you’re not a fan of Mercury check out the Ford and Mazda versions (remember they’re all part of the same company) for some variation with the same stats.

Even if the thought of an alternative fuel vehicle isn’t yet in your budget, consider buying a smaller car. Check out the EPA’s website to see how smaller vehicles rate on their emissions and greenhouse gasses. Many are almost as highly rated as those on this list. Remember the number one rule of being green is to be conscious of what you’re buying and it’s impact on the environment. Happy driving everyone and don’t forget to buckle up!