Roof condensation as water source

[Radiopeg]

I came across this article about a house in Thailand. This one part stumps me for getting more info. Here is the quote: "Some 30 to 40 litres are collected daily on the roof, thanks to a special surface which lowers its temperature at night. Water is then condensed out of the breeze, which is channelled across it by landscaped mounds in the garden." Does anyone have a clue? The builder also makes his cooking gas from yard clippings.

here is full text article http://www.terradaily.com/2003/030928033...axajn.html