Want to charge your mobile device? Either plug it into your computer, a power outlet, or maybe even a powerbank if you’re on the go. However what if you don’t have access to a power outlet, or what if your powerbank is out of juice? Thankfully there is an invention by Ann Makosinski, an 18-year old student who created a mug that can charge your phone.

How does this work? Basically the idea is that it uses residual heat from the hot drink in your mug to charge your device. This isn’t Makosinski’s first invention either. When she was 15, she invented a flashlight that would be powered by your body-heat, so this is definitely not the first that time she has explored the idea of using heat as a power source.

According to Makosinski, the idea was borne to solve two issues: coffee that is too hot to drink, and smartphones with batteries that die too fast. Thanks to her invention, the teen was also awarded $50,000 from Shell this month for her resolution to “reduce the impact on the electrical grid by patenting body-heat-generated power.”

While you can’t actually go out and buy this charging mug just yet, it does show an interesting path that Makosinski is headed down, and we can’t wait to see what other environmentally-friendly inventions she might come up with in the future. In the meantime, check out the video above where she appears on Jimmy Fallon’s show to demonstrate the mug in action.

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