Nikola Tesla is best known for developing the alternating current system that power grids use. It beat out direct current as a more effective power transmission system over long distances. Beyond that, Tesla conducted all sorts of mechanical and electrical experiments, among them an early contribution to x-ray imaging. He experimented with wireless lighting and wireless communication between electrical devices. He started a project intended to transmit wireless signals and power between continents, called the Wardenclyffe Tower, but he ran out of funding before he could finish it. He died on January 7, 1943, at the age of 86. The SI unit for magnetic flux density, an electric engineering award, and an electric car model were named after him in that order.