The walls and exterior skin is used as a translator of energy. (passive) Imagine if the the dirt and bricks were embedded with photovoltaic chips as well or chloroplast-like cells that could not only keep the building cool and warm but transfer the energy to light and power for the inhabitants. This existing "dead" system could have a new life of its own.
Chloroplasts, the organelle that turns light into energy through photosynthesis, have been the long time inspiration for the solar panels as we know them. To this point they are still large and not nearly as integrated as their original inspiration. But let's get a bit smaller. Material scientists at the Nano/Bio Interface Center of the University of Pennsylvania have taken it there. They have demonstrated the transduction of optical radiation to electrical current in a molecular circuit. The system, consisting of an array of nano-sized molecules of gold, respond to electromagnetic waves by creating surface plasmons that induce and project electrical current across molecules, similar to that of photovoltaic solar cells.
Dawn Bonnell, a professor of materials science and the director of the Nano/Bio Interface Center at Penn, and colleagues fabricated an array of light sensitive, gold nanoparticles, linking them on a glass substrate. By minimizing the space between the nanoparticles to an optimal distance, researchers used optical radiation to excite conductive electrons, the plasmons, to ride the surface of the gold nanoparticles and focus light to the junction where the molecules are connected. This plasmon effect increases the efficiency of electrical current production in the molecule by a factor of 400 to 2000 percent, which can then be transported through the network to the outside world. Pretty amazing. These new cells could be infused into even clothing. Just think about it.