Improvement of PV cell efficiency by rectifying antenna

Solar cells built from single-crystalline silicon, as alternative energy sources, became the most widely used in recent years. The main stream manufacturing approach is to process silicon solar cells from Si wafers, and then assemble these cells into photovoltaic modules. However, a significant portion of solar energy, corresponding to the infrared radiation with wavelength in the range 1-3 μm, is lost. According to the known solar spectrum, the solar energy coming to Earth in the diapason of 1-3 μm equals to ∼ 216 W/m². In this work, we present an investigation of a new system which is capable of utilizing the radiation energy in this frequency band. This novel converting system is based on rectification of the very high frequency radiation with a nano-dimensional antenna and rectification with a metal-insulator-metal thin film system. This system represents a tunneling diode, made of metals with various work-functions separated by a thin dielectric layer. To test the efficiency of this novel converter and the choice of parameters of thin films we used a computer modeling of the system. Modeling and simulation were performed using PSpice. It was shown that a short circuit current may reach the value of 46.2 nA and the open circuit voltage can reach 4.62 mV for a single antenna. It was found that the optimum load resistance equals to 175-200 Ω, which provides a maximum generated power of 35 fW for a single antenna. Efficiency of the loaded system reaches up to 16.33%.