Physics of solar cells nelson pdf

Name: HW #1 Solar Cells EEE 565, Fall '20 Prof. Richard King Please print out the homework assignment and complete it with pencil or pen. To submit it, please scan it to form an Adobe pdf document, and upload it in the Assignments section of the Canvas website. For consistency, please use the value kT/q = 0.02585 V at 300 K in your calculations. Unless noted otherwise, assume the semiconductor in the problems is silicon, with ni = 1.0 × 1010 cm-3 at 300K. If there is a computer simulation or Excel spreadsheet involved in the homework: Please make 1 or 2 pages that show the key figures, input values, and answers from the simulation or spreadsheet, and please make a pdf copy of those pages. Please join that to the scanned pdf file of the rest of your homework, to form one homework file for upload. Please also upload the computer simulation or Excel spreadsheet that you wrote yourself to solve the problem. A small part of the grade for the problem will based on uploading this file. However, the main part of the grade for the problem will be the pdf pages showing the key figures, input values, and answers that you attach to the rest of your homework. ________________________________________________________________________________ 1. Consider two solar cells of equal area with J-V characteristics that are well described by the ideal diode equation, with diode ideality factor γ = 1.2 . Cell 1 has Voc = 1.4 V and Jph = 16 mA/cm2. Cell 2 has Voc = 0.7 V and Jph = 24 mA/cm2. Minority-carrier collection is efficient in these cells, so that Jsc ≈ Jph . (a) (15 pts) Solve the diode equation for Jo algebraically, and find the numerical values of Jo,cell 1 and Jo,cell 2 in units of A/cm2 . Please be sure to show your work.

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(b) (15 pts) When the cells are connected in series, find algebraic expressions for Voc and Jsc of the 2-cell combination. For values of Jo,cell 1 = 4.0 × 10-22 A/cm2 and Jo,cell 2 = 3.8 × 10-12 A/cm2, what are the values of Voc and Jsc ? (c) (15 pts) When the cells are connected in parallel, find algebraic expressions for Voc and Jsc of the 2-cell combination. What are the values of Voc and Jsc in this case ?

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2. (25 pts) Q3., p. 328, in Nelson, The Physics of Solar Cells

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3. (a) (10 pts) What is one important reason why you became interested in solar cells? (b) (20 pts) Find a paper on photovoltaics that interests you, from a peer-reviewed journal or conference proceedings, and please email it to me with the subject: PV article. Please describe: what do you find interesting about the paper?