Scientists develop see-through film that rejects 70% of incoming solar heat. The material could be used to coat windows and save on air-conditioning costs. The film is able to remain highly transparent below 32°C/89°F. Above this temperature the film acts as an “autonomous system” to reject heat.

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Scientists develop see-through film that rejects 70% of incoming solar heat. The material could be used to coat windows and save on air-conditioning costs. The film is able to remain highly transparent below 32°C/89°F. Above this temperature the film acts as an “autonomous system” to reject heat.