A stay-at-home mom watches soap operas for 1.5 h each day and her husband vegges out in front of the tube for around 2 h a night
He also watches the football games on Saturday and Sunday during football season (two games each day, 6 hours of watching). How much does this family pay to watch TV every year? Assume the cost of electricity is $0.08/kWh.
We assume from the description that this is the weekday ritual—watching the TV
for a total time of 3.5 h. From Table 8.7, we use 200 W as the power drawn by the TV. So,
we find 5 d x 3.5 h/d x 200 W = 3500 Wh = 3.5 kWh. Weekend watching totals 12 h, so
energy use from the weekend totals 200 W x 12 h = 2400 Wh = 2.4 kWh. Total weekly
energy use is 5.9 kWh. The cost is 5.9 kWh x $0.08/kWh = $0.47.
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