The emergence of Organic Electronics during the last 20 years brought forward the unprecedented properties that polymers can offer in electronic devices. Polymers find applications in cutting-edge technologies, such as energy harvesting devices, sensors and actuators, light emitting diodes and many others. All these devices benefit from the functionalities bared by polymers, combined with their flexibility, ease of processing and low price. These merits make polymers particularly interesting in view of the forthcoming era of the Internet of Things. In this talk I will highlight the critical role of the nanostructure of polymeric active layers in the performance of the electronic devices that integrate them. The studies that will be presented are focused on three energy-related applications, namely, polymer photovoltaics, thermoelectrics and piezoelectric nanogenerators, and provide an overview of my research activities during the last 7 years.