US Patent 11785848 Heat to electric conversion

An energy conversion system for use in a rifle with a barrel and a handguard includes an interface with a curved surface that conforms substantially to a curvature of the barrel such that the curved surface receives heat from the barrel. The interface further includes a substantially flat mounting surface and a heat-conducting material disposed between the curved surface and the substantially flat mounting surface to conduct the heat from the curved surface to the substantially flat mounting surface. Moreover, a spring is positioned to be between the interface and the handguard to apply a force to the interface so that the curved surface substantially maintains contact with the barrel. A thermoelectric generator is secured to the substantially flat mounting surface and includes a positive lead and a negative lead.