3M showed new window film that both cuts infrared light transmission through the glass and collects solar power from both indoor and outdoor lightsources. A square meter of the film can generate enough electricity to charge an iPhone under peak sunlight.

This film has two strong energy conservation traits. The first is that it generates electricity. The second is that it blocks heat. The film generates electricity, so it can be used to power things like LED lights. As for blocking heat, this can help conserve energy, because if heat is blocked then the air conditioning of a building can be lowered, saving electricity. Those are the two main advantages for energy conservation.

The film blocks or absorbs about 80 percent of visible light and 90 percent of infrared light. In this demonstration at Ceatec in Japan the company showed the temperatures on each side of the glass, with the inside thermometer about ten degrees lower than the outer one.

The film comes in flexible sheets and can be glued onto windows. There’s a greenish tint to the film, but 3M plans to make it clear by the time it plans to commercialize it sometime in 2012.

The film generates only about a fifth of the electricity that a traditional silicon solar panel does and will cost about half as much, though pricing hasn’t been announced.