Well, not the whole US. But this week the US Environmental Protection Agency kicked off a major campaign to convince Americans to switch their light bulbs to more energy efficient ones.

Somewhat weirdly (we think), the campaign is taking the form of a bus tour. It seems to be a popular trend: Toyota recently got some big trucks to hit the road to promote its energy efficient cars. We don’t really get it, to be honest.

Still, it’s for a good cause. Check out the potential impact it could have, according to the EPA:

 If every U.S. household changed just one light bulb or fixture to an Energy Star bulb, each year our country would save $600 million in energy costs, enough energy to light 3 million homes, and prevent greenhouse gases equivalent to the emissions from more than 800,000 cars. Lighting accounts for about 20 percent of a home’s electricity use. Energy Star qualified light bulbs and fixtures use about 75 percent less energy than standard incandescent lighting, with bulbs that last six to ten times longer. One Energy Star qualified bulb can save about $30 or more in energy costs over its lifetime.

• Green certified homes sell faster, higher price