Best colour to paint something to keep cool

[james26]

Hi, could anyone tell me please, what would be the best colour to paint a boat to keep the cabin cool in a tropical climate?

I think the answer probably is white because it will absorb less radiation, but I'm not sure because of course it will also emit radiation better as well.

Any thoughts appreciated.

 

[tiny-tim]

welcome to pf!

hi james26! welcome to pf!

I think the answer probably is white because it will absorb less radiation, but I'm not sure because of course it will also emit radiation better as well.

(you mean, it will emit radiation worse )

the boat will absorb heat mostly through radiation, but it will emit heat mostly through convection

so the colour won't really affect the rate at which it emits heat

 

[turbo]

White would be best, because it won't absorb as much solar energy as darker colors. Therefore, there won't be as much IR to have to emit. Ever been to a boat-yard or pier? White predominates.

 

[james26]

Oh, yes, I did mean worse..

How do you know it will absorb most by radiation and lose most through convection?

Also, how significant is the visible spectrum in terms of heat transfer? Is it as important as the IR region? And does the ability of a surface to absorb/emit in the visible region strongly correspond to the same in the IR region?

Many thanks.