Transmissive Spectrum-Splitting Concentrator Photovoltaic Cells And Modules

Novel transmissive concentrator multijunction (TCMJ) solar cells, and their corresponding module, are here introduced and demonstrated as a promising component of a hybrid concentrator photovoltaic/concentrated solar thermal power (CPV/CSP) system. Using this system, incoming concentrated light can be effectively split into two parts; "in band", shorter-wavelength light is absorbed into the TCMJ solar cells to generate electricity, and "out-of-band" light transmits through the cells and module to a thermal receiver where photons are collected as heat that may be used for a variety of purpose. When on-substrate cells are employed, the in-band power conversion efficiencies measured under 1 sun at room temperature are 34.7% and 35.8% and the energy-weighted out-of-band light transmission is 68.6% and 60.8% for the TCMJ cell and module, respectively. We also demonstrate the stability of TCCMJ cells and modules via thermal cycling and show that the temperature of the TCMJ module can be controlled under 105'C via transparent active cooling microfluidic channels. Thin-film cells fabricated by means of the epitaxial lift-off (ELO) technique are being developed to enhance both the spectrum splitting efficiency and cost effectiveness of this TCMJ module.