Question

Electric power is less expensive at night because:

w) more hydroelectric generation is brought on line at night.
x) there is less demand at night.
y) pollution control is less stringent at night.
z) power plants are more efficient at night.

Answer 1

x) there is less demand at night

Step-by-step explanation:

Electric power and it's the price is dependant on the level of demand it has, there are peak and off-peak times during the day, generally speaking during the night (between 10 pm and 7 am) electricity has lower demand.

The existence of peak times at a day is the reason why hydroelectric generation is lower at night, normally in peak off times the hydroelectric generator stores water for when the demand increases, same happens with powerplants at night not being as efficient as they are during the day when the energy is more needed. Finally, pollution control is stringent at all times of the day, its not related to the demand.

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