Thang P D and Preston T R 2014:  
Solar panels for decentralized production of electricity; direct use in a 12V refrigerator requires  less energy than when the current is inverted for a 230V AC refrigerator. 
 Livestock Research for Rural Development. Volume 26, Article #171. 
 Retrieved 
, from http://www.lrrd.org/lrrd26/9/than26171.html