Question

Your friend decides to go off gridand generate their electricity with a stationary bicycle electric generator (solar not an option at their cabin in the deep redwood forest). They have only two essential items that require electricity: a laptop and refrigerator. The laptop uses 45 W to operate, and a small (2 cubic foot)energy efficient refrigerator uses 30 W. Your friend schemes a plan to ride the bike to charge batteries to run the laptop and refrigerator. The pedal powered generator produces 100 W. Lithium-ion batteries have a high efficiency for charging and discharging electric energy; close to 99% for charging, and some loss discharging. So as a first approximation, do not consider storage loss, but recommend to your friend that they use a Li-ion battery bank.

a) Your friend wantsto run the laptop 4 hours per day, and the refrigerator needs to run for 24 hours every day.Calculate how long your friend will have to pedal the generator each day to make this work.

b) As an option, your friend reconsidersconnectingto the grid and pay PG&E the going rate of $0.20 per kWh, calculate their monthlyelectricity bill with the usage described above?

Answer 1

72 0 41 eA 0.9 にんhns