Did you check out the cool roof project mentioned in the last post? I came across it quite a while back when I had an idea about using pigments like the color shifting cars to give roofs two different looks, one to the Sun and one to the ground. The pigment systems turn out to be too expensive to use in roofing where CHEAP rules. If you have priced roofing you'll say it is not cheap but on a per pound and per square foot basis it _is_ cheap. That business depends on low cost inputs, the pigments binders and fibers all have to be cheap and durable so you can afford to use lots of it and still pay for all the labor involved in installing it. It was an interesting lesson in manufacturing costs for me.

Anyhow. The idea of a roof looking one way to the sun and another to the passers by is pretty compelling even if the color shifting system cannot be applied. The idea was that for the direct light of the sun (the primary lighting on the roof) is for the most part not bounced to our eyes. Most of it is absorbed and or reflected elsewhere. The absorbed bit during the summer is the worrisome bit. All that heat... Thus the silver roofing in places where we cannot see the roof. Silver paint is pretty ugly and buildings do have to keep up appearances.

OH, a neat story I think I read in Amory Lovin's Natural Capitalism about a building superintendent who, once he learned about cool roofs and had some tie to the cost (I forget how he was incentiveizd) made it a practice to mop the silver roof to keep the absorptive dust down to a minimum. This tiny act took a part of a morning and paid off over and over in a big way in reduced energy costs. One morning and a bucket of mop water.

Funny book that, full of adoration for what turned out to be the fraudulent Enron and for a long while the website of the book stood like a ghost town. (I took a look for it again and the participation part where passersby could tease them about the Enron bits was not there anymore.)  But the book is not all bunk. Lots of interesting systems thinking and reminders about how misaligned the incentives are in so many economic relationships and energy systems.

Ok... this has been sitting in the draft folder too long.  More soon.