By integrating innovative solar radio technology, we are using light as a natural energy source for our modern wireless system EasySens. Our wirless sensors have neither a need for batteries nor for external power supply. There are no time-consuming and cost-effective wirings. Low material costs and time saving are supporting the realization of reasonable system solutions. EasySens offeres considerably more flexibility with regard to the sensor positioning. Thus, a changeable room layout in modern office buildings is no problem at all. Even in protected historic buildings, in which no architectural changes are allowed, sensors for the air-conditioning technology can be easily integrated.