If your celebrations this 4th of July include a car, you'll probably be stopping at a gas station somewhere down the road. And while filling up isn't really green, there are some ways to make it a little greener.

Every gallon of gasoline creates 20 lbs of CO2, which is like sending a one-square-foot column of greenhouse gas up through the entire atmosphere every time you empty the tank.* So before you pull into the pump, choose an eco-friendlier gas station.

The Sierra Club ranked eight of the largest oil companies for their social and environmental practices. Not surprisingly, not one had a spotless record. However the non-for-profit undauntedly categorized the companies into three groups which we'll call The Better, The Bad, and The Worst.

The Better

BP (Has BP ruined its eco-rep? Read about their efforts to increase pollution in the Great Lakes here)

Sunoco

The Bad

Royal Dutch Shell

Chevron

Valero Energy Corporation

Citgo

The Worst

ExxonMobil

ConocoPhillips

Although the study criticized BP and Sunoco (Sunoco, Ultra Service, APlus) for recent oil spills in Alaska and Pennsylvania, it praised both oil companies for reducing greenhouse gas emissions in their operations and supporting environmental groups. BP has also committed $8 billion to alternative energy research.

Alternatively, ExxonMobile has denied man-made climate change and lobbied against the Kyoto Protocol. It is also seeking to drill in the Artic National Wildlife Refuge. Like its partner in the bottom group, ConocoPhillips (76, Conoco, Phillips 66) opposes manadatory caps on greenhouse gas emissions. It has also been cited for more than 470 violations by the EPA.

So wish our country a Happy Birthday and send a message to the oil companies: Americans want greener energy, even at the gas pump.

Read the Sierra Club's report by clicking here.

Thoughts on today's article? Post them below.

______________________
*assumes a 12 gallon tank