Question

The process of converting energy produced by wind turbines into electricity is about 40 percent efficient. If the transport of electricity is 90 percent efficient and fluorescent light bulb efficiency is known to be 20 percent, what is the overall efficiency for converting wind into fluorescent lighting

Answer 1

Answer: 7.2%

Explanation:

Given

Efficiency of converting energy produced by wind into electricity is about $\eta_1=40\%$

Transport of electricity efficiency $\eta_2=90\%$

Fluorescent light bulb efficiency is $\eta_3=20\%$

Overall efficiency is the product of all the efficiencies i.e.

$\Rightarrow \eta=\eta_1\times \eta_2\times \eta_3\\\\\Rightarrow \eta=0.4\times 0.9\times 0.2\\\Rightarrow \eta=0.072\ \text{or}\ 7.2\%$

Therefore, the overall efficiency is 7.2%