Considerations on the Solar Cell

T h e considerations reported in this paper h a v e been stimulated by t h e current interest in t h e solar b a t t e r y as a power supply for i n s t r u m e n t s and t r a n s m i t t e r s in satellite and space probe vehicles. A n u m b e r of space vehicles! h a v e contained solar b a t t e r i e s w i t h peak o u t p u t s ranging f r o m several w a t t s to several h u n d r e d w a t t s . It h a s been d e m o n s t r a t e d t h a t solar b a t t e r y power supplies are technically feasible, not only in space vehicles but also in terrestrial telephone systems. 2 F o r t h e latter t y p e of application, however, t h e solar b a t t e r y has been found to be not competitive economically with several other available power supplies. 2 However, it is highly a d v a n t a g e o u s for space vehicles because of its a d v a n c e d development a n d commercial availability, light weight, reliability and long life. T h e long life is d u e not only to t h e ruggedness a n d p e r m a n e n c e of its s t r u c t u r e and t h e absence of moving p a r t s or t For a review of the use of solar batteries in space see Daniels. 85