Researchers at MIT have developed a new type of transparent polymer film that’s capable of storing solar heat and saving it for later use. While conventional solar cells harvest energy from the Sun and store it in the form of electricity, this unique new material can hold on to the Sun’s energy indefinitely in a chemical state, the researchers claim. When it’s ready to be used, that energy can be activated through a controlled blast of heat, light, or electricity. 

The film is so ultra-thin that it could have applications in a wide range of products, they say, including being woven into fabric to create sweaters that warm up on command or sandwiched between two sheets of glass to make a windshield that heats up automatically in icy weather. While many rear car windows come equipped with heating wires for this purpose, they’re not placed in front windows in order to keep the driver’s view clear. With MIT’s new film, all it would take is a small pulse of electricity for a surface to heat up as much as 50°F, they say.   

The material could also have revolutionary applications when it comes to energy efficiency. In cold temperatures, electric cars devote a large chunk of energy to heating and de-icing, reducing their driving ranges by as much as 30 percent. By storing extra heat in a chemical state, the car's battery would be free to use its energy for other purposes.

The researchers are currently in the process of fine-tuning their product. Before it’s released commercially, they hope to eliminate the material's slight yellow tinge and make it completely transparent. They also hope to raise its heating potential from 50°F to 68°F.

Why the mentions of its potential use in cars? Perhaps because BMW was one sponsor of the project. So don’t be surprised if the technology turns up in their vehicles sometime in the future. You can find the team's full findings in the journal Advanced Energy Materials. 

[h/t: Fast Company]