Photovoltaic Systems Engineering SEC598F17 Photovoltaic Systems Engineering Session 08 PV Systems Components Solar Modules – Part 1 September 14, 2017

Session 08 content PV System Components Solar modules – fabrication Solar modules – operation Solar modules – reliability, lifetime, etc.

Learning Outcomes Introduction to module science and technology Consideration of module performance, reliability, lifetime, and decommissioning

PV Systems: Solar cell I vs V There is a relation between the current and the voltage of a solar cell: Increasing light

PV Systems: Need for the solar module To increase the electrical power, solar cells are combined together (physically and electrically) into solar modules 6.5A, 0.6V, 4W 6.5A, 45V, 300W

PV Systems: Solar module I vs V The relation between the current and the voltage of a solar module resembles that of the single solar cell: 60 solar cell module Increasing light

PV Systems: Solar module construction Solar cell electrical wiring Edge view of module

PV Systems: Solar module construction Suntech - Cell and Module Manufacturing: https://www.youtube.com/watch?v=IAufbqbUS6k

PV Systems: Solar module construction Bosch – Solar Module Manufacturing: https://www.youtube.com/watch?v=CiYfcZJmBNE

PV Systems: Solar module operation Deutsche Gesellschaft für Sonnenenergie, Planning and Installing PV Systems

PV Systems: Solar module operation, cont. Reverse Bias Forward Bias PVCDROM

PV Systems: Solar module operation But consider the case of two diodes in series PVCDROM

PV Systems: Solar module operation Under all conditions for two solar cells connected in series (open circuit, short circuit, or in-between) and

PV Systems: solar module operation For the special case of the two solar cells in series at open circuit, and

PV Systems: Solar module operation For the special case of the two solar cells in series at short circuit, and

PV Systems: Solar module operation Graphical solution of current flowing through two mismatched diodes in series (at short circuit)

PV Systems: Solar module operation Now consider the case of ten diodes in series PVCDROM

PV Systems: Solar module operation At short circuit, and

PV Systems: Solar module operation One shaded cell in a string reduces the current through the good cells, causing the good cells to produce higher voltages that can often reverse bias the bad cell. Heat dissipated in a shaded cell caused the module to crack PVCDROM

References for Solar Modules Deutsche Gesellschaft für Sonnenenergie, Planning and Installing PV Systems, Chapter 2 S.Bowden and C.Honsberg, PVCDROM S.R.Wenham, M.A.Green,M.E.Watt, R.P.Corkish, A.B.Sproul, Applied Photovoltaics, 3rd Ed., Earthscan, 2011, 978-1-84971-141-8