Now your sweaty body can power your phone. Like Neo in the Matrix, a new system created by researchers at North Carolina State University lets you generate electricity with a wearable device. Previous systems used massive, rigid heat sinks. This system uses a body-conforming patch that can generate 20 μW per centimeter squared. Previous systems generated only 1 microwatt or less.

The system consists of a conducive layer that sits on the skin and prevents head from escaping. The head moves through a thermoelectric generator and then moves into an outer layer that completely dissipates outside the body. It is 2mm thick and flexible.

The system, which is part of the National Science Foundation’s Nanosystems Engineering Research Center for Advanced Self-Powered Systems of Integrated Sensors and Technologies (ASSIST), has a clear path to commercialization.

The goal is to embed these into health tools that can measure your vital signs without needing to be recharged. “The goal of ASSIST is to make wearable technologies that can be used for long-term health monitoring, such as devices that track heart health or monitor physical and environmental variables to predict and prevent asthma attacks,” said researcher Daryoosh Vashaee, an associate professor at NC State. “To do that, we want to make devices that don’t rely on batteries. And we think this design and prototype moves us much closer to making that a reality.”