Back home I had a attic fan the kept the home cool.

Sun came up, solar panel powered a fan to vent the attic and remove the heat build up

Sun goes down, fan stops, but also no need with the sun down.

SImple and easy. Anyone seen somthing like this here ?

I've thought about that too, but haven't found any suppliers where I'm at in Pattaya. I'm now considering the following convection vent with no fan, unless someone can suggest something else available in Thailand;

These guys may be able to help.....

http://www.engineo.co.th/

I have seen solar-powered vents in Australia, imported from the US I believe, probably made in China. The only passive roof ventilation I could find in Phuket was at HomeWorks and similar to this >

They are called whirlybirds or spinners, and easily fitted to all roof types and pitches. An alternative, is to install a 240v high volume wall vent high up in a gable end.