Energy Secretary Steven Chu has advocated painting roofs white as a cost saving measure that also reduces the impact of climate change.  The theory is that more heat would be reflected, thereby lowering a building’s cooling costs, which in turn reduces greenhouse gas emissions because we’re using less power to cool the building.

An article (blog entry) on Time magazine’s website says studies have concluded that whitening a roof actually works and can make it 20% more cost effective to cool your house on hot days.  I’d love to see links to the studies, but the physics makes enough sense that I believe it.

You can read the article here:  http://cheapskate.blogs.time.com/2009/07/30/why-isnt-your-roof-white-already/

Here in sunny South Carolina, I spend more on air conditioning in summer than I do on heating in winter.  When my roof is due for an overhaul (and those shingles are getting pretty old), I will be looking into a light colored rooftop.