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Converting sunlight to electricity with solar cells has an efficiency of 15%. It's possible to achieve a higher efficiency (though currently at higher cost) by using concentrated sunlight as the hot reservoir of a heat engine. Each dish in the figure concentrates sunlight on one side of a heat engine, producing a hot-reservoir temperature of 500 degrees Celsius. The cold reservoir, ambient air, is approximately 30 degrees Celsius. The actual working efficiency of this device is 30%. What is the theoretical maximum efficiency?

Solved it thanks

efficiency = 1- Tc/Th= 1- (273+30)/(27+500)

= 1- 0.39 = 0.608

=0.608 x 100 = 60.8 %

61.3

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