Solar Reflective Car Shells: Simple as Black and White?

You’ve heard the sad tales about dogs (and yes, even children) trapped in hot cars as there owners go to do some shopping. Anyone who’s opened up a car door after it’s been sitting in the summer sun for even a few minutes knows how hot they can get. Cars painted black are the worst. So what if you had a lighter colored car? Would such a simple change have an effect on the heat that builds up inside on a sunny day? Would there be some kind of positive impact on your budget or even on the environment? Scientists at Lawrence Berkley National Lab recently released a study they conducted on the efficacy of solar reflective paints on cars; basically, lighter colored cars. They found that up to 60% of the total sunlight can be reflected by having the right color paint.  From their website:

A light-colored or cool-colored car shell reflects more sunlight than a traditional dark car shell. This cools the cabin air and reduces the need for air conditioning. A recent study found that after parking in the sun for an hour, a silver Honda Civic (shell SR 0.57) had a cabin air temperature about 5-6°C (9-11°F) lower than an otherwise identical black car (shell SR 0.05). Modeling indicates that substituting a silver (or white) shell for a black shell would allow the specification of a 13% smaller (lower capacity) air conditioner, improving fuel economy.
Cool cars can benefit drivers, cities, and the planet.

• Fuel savings. Substituting a cool shell for a conventional black shell permits the use of a smaller air conditioner, improving fuel economy by 1% (for a cool colored shell with 35% solar reflectance) to 2% (for a white or silver shell with 60% solar reflectance).
• Better air quality. Specifying a smaller air conditioner reduces tailpipe emissions of nitrogen oxides, carbon monoxide, and hydrocarbons.
• Slowed climate change. Specifying a smaller air conditioner reduces tailpipe emissions of carbon dioxide. Cool car shells also reduce the flow of heat from vehicle to atmosphere.

Take a look at the image in this post to see how high in the triple digits the inside of Eric’s Honda got last summer.

[Image by 2nd Green Revolution]