archives@tulane.edu / As global energy consumption continues to grow, new paths towards renewable energy generation are needed to reduce environmental impact and allow for more zero-net energy development. This includes not only electricity generation but also energy required for thermal applications. This dissertation explores three different technologies to generate electricity and high temperature heat simultaneously by using an actively tracked parabolic dish concentrator (2.72 m2) and an all-in-one hybrid receiver. This hybrid receiver usually consists of two key components, a PV module assembled with multijunction solar cells based on III-V materials, and a thermal receiver that transfers absorbed solar energy into a working fluid for a variety of commercial and industrial process heating applications. A key goal of this work is to use spectrum splitting and other design innovations to operate PV cells at much lower temperatures than the thermal receiver output temperatures. PV cooling is critical for PV modules to sustain high energy conversion efficiencies and to work for longer duration under concentrated light. A key distinction in different designs reported here is how the PV cells are cooled, either “transmissive microfluidic cooling”, “transmissive direct fluid cooling”, and “non-transmissive microfluidic cooling”. All three technologies show good performance for both efficient PV cooling (< 120°C) and high system energy conversion efficiency (> 80%).
This dissertation is divided into four key chapters. Chapter 2 discusses spectrum splitting CPV with transmissive microfluidic cooling, focusing on the optical performance of the PV modules. By applying a transfer matrix-style approach, the cumulative transmission through the entire PV module is calculated: these results are verified experimentally. By doing so, the power collected by the PV cells and thermal receiver can be predicted. Chapter 3 explores a spectrum splitting hybrid receiver design using a cheaper and more straightforward cooling method that flows silicone oil across PV cells to extract their waste heat and to eliminate the use of sapphire for cost reduction. The cooling performance is verified by outdoor tests and the system efficiencies are discussed under different solar concentration. Chapter 4 investigates another hybrid receiver design that utilizes waste heat from high efficiency PV cells to preheat the working fluid in the thermal receiver instead of dumping the energy to surroundings as in the previous two methods. This design allows both the cells and the thermal receiver to be illuminated with concentrated sunlight simultaneously without the need for spectrum splitting. The electrical and thermal performance are tested both in the lab and outdoors. Chapter 5 discusses a proposed way to enhance the transmission of the spectrum splitting III-V solar cells used in Chapters 2 and 3. Epitaxial lift-off is used to remove the III-V cell substrate and to fabricate highly infrared-transmissive, spectrum-splitting thin-film solar cells. In summary, we explore the power collection performance, including optical, electrical, and thermal aspects, for these hybrid solar receiver technologies, enabling their use in a number of promising applications. / 1 / Yaping Ji
Identifer | oai:union.ndltd.org:TULANE/oai:http://digitallibrary.tulane.edu/:tulane_120419 |
Date | January 2020 |
Contributors | Ji, Yaping (author), Escarra, Matthew (Thesis advisor), School of Science & Engineering Physics and Engineering Physics (Degree granting institution) |
Publisher | Tulane University |
Source Sets | Tulane University |
Language | English |
Detected Language | English |
Type | Text |
Format | electronic |
Rights | No embargo, Copyright is in accordance with U.S. Copyright law. |
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