Page 29 - Demo PravySoft Ezine

NET ELECTRONICS MODULE I

Figure 1. 72: Typical solar spectrum at the top of the atmosphere
and at sea level. ............................................................................ 271

Figure 1. 73: Typical solar spectrum for different air mass
conditions ..................................................................................... 272
Figure 1. 74: Principle of operation of a pn junction solar cell. ..... 273

Figure 1. 75: Photo generated carriers in a solar cell due to
absorption of light. ....................................................................... 275
Figure 1. 76: Finger electrodes on a pn junction solar cell. (Prin.of E
Mat. S.O. Kasap) ........................................................................... 276

Figure 1. 77: (a) pn junction solar cell under illumination with an
external load. The equivalent circuit (b) without and (c) with an
external load. ................................................................................ 281

Figure 1. 78: (a) A solar cell connected to an external load (b)
PravySoft Ezine demo
PravySoft Ezine demo
Equivalent circuit, with a constant current source, a forward-biased
pn junction and the external load. ................................................ 282
Figure 1. 79: I−V characteristics of Si pn junction solar cell under

dark conditions and under illumination with light of increasing
intensity. ....................................................................................... 284
Figure 1. 80: I-V curve for a solar cell with maximum power

indicated by the shaded area. ...................................................... 287
Figure 1. 81: Solar cell efficiency as a function of band gap of the
semiconductor material. (Phy. Sem dev, S.M. Sze) ....................... 288
Figure 1. 82: Tandem solar cells ................................................... 292