Colorful films could help buildings, cars keep their cool
The cold blast of an air conditioner can be a welcome relief as temperatures soar, but "A/C" units require large amounts of energy and can leak potent greenhouse gases. Today, scientists report an eco-friendly alternative—a plant-based film that gets cooler when exposed to sunlight and comes in a variety of textures and bright, iridescent colors. The material could someday keep buildings, cars and other structures…