Modeled on man: Breathable skin for buildings

One major obstacle this technology will face-- even in regions where ambient air temperatures are appropriate-- is control. The bimetal strip can only act based on its local temperatures.

By contrast, the amount of heating or cooling a building needs generally is set by the distributed conditions throughout the building. For example, many commercial buildings require cooling in the core throughout the year-- without regard for the insolation or the air temperature at the envelope. So this technology will not, in many cases, eliminate the need for mechanical assist.

Another aspect of the control problem is the wishes of occupants in the perimeter spaces. As described, the incident sunlight, or the interior temperature, are meant to control the porosity of the material. Thus occupants get no say in the amount of sunlight they get, or the amount of air passing through the wall.

Competing technologies allow much more control. For example, "smart glass" can regulate the amount of light entering a space, either in response to occupants, or to a building-level controller. Passive inlet vents can maintain a desired airflow rate, in the face of changes in wind pressure and indoor-outdoor temperature differences (controlling to airflow, rather than to local temperature, is desired for air quality reasons).

My issue with exciting things like this and solar heating is that in most cases we are nowhere near the technological limit of climate control efficiencies that can be achieved with a reasonable amount of effort.

My aunt was selling solar heating in Minnesota. People would be really interested until they found out the first step was doing a really thorough (and somewhat costly) job insulating the house, which provides more energy savings than the solar panels themselves in most cases (it's certainly more cost-effective). They didn't really care about saving energy, they just wanted solar panels as a status symbol.

As long as energy remains subsidized and people don't have to pay for the externalities they create by polluting, eco-friendly innovations like hybrid and plug-in electric cars, solar power, and breathable skins will remain of interest only as status symbols and badges of group identity.

(as an aside, Europe and Japan seem to do a better job of actually giving people financial incentives to waste less, although people should correct me if my view is naïve)

I am very glad to learn of the Humans Invent website — I was not aware of it. I love to read about innovation, science and the like. It reminds me that in the midst of many challenges in the world there is great work going on that could address some very important issues.

Long live human ingenuity!

In tropical climates such as Cuba's thermal capacitance via masonry is a feature of Colonial architecture (and not one typically available to Florida's stick framed bungalows). Another feature of traditional architecture is high ceilings to take advantage of convection - something not uncommon to Florida's bungalows from the early 20th century.

This was 5 years ago and one year ago, so it's not pre-revolutionary nostalgia. I might be wrong on how well it worked inland, but I remember feeling cool no matter which city I traveled to.

This was October to May, so like I said, the system may break down in summer. It was still warm through those months compared to what I know in Canada, but I know summer is warmer still.